Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
Analysis of Coiled-Tube Heat Exchangers to Improve Heat Transfer Rate With Sp...IJMER
Steady heat transfer enhancement has been studied in helically coiled-tube heat exchangers. The outer side of the wall of the heat exchanger contains a helical corrugation which makes a helical rib on the inner side of the tube wall to induce additional swirling motion of fluid particles. Numerical calculations have been carried out to examine different geometrical parameters and the impact of flow and thermal boundary conditions for the heat transfer rate in laminar and transitional flow regimes. Calculated results have been compared to existing empirical formula and experimental tests to investigate the validity of the numerical results in case of common helical tube heat exchanger and additionally results of the numerical computation of corrugated straight tubes for laminar and transition flow have been validated with experimental tests available in the literature. Comparison of the flow and temperature fields in case of common helical tube and the coil with spirally corrugated wall configuration are discussed. Heat exchanger coils with helically corrugated wall configuration show 80–100% increase for the inner side heat transfer rate due to the additionally developed swirling motion while the relative pressure drop is 10–600% larger compared to the common helically coiled heat exchangers. New empirical Co-relation has been proposed for the fully developed inner side heat transfer prediction in case of helically corrugated wall configuration.
experimental investigation of heat transfer intensification of pin fins under...INFOGAIN PUBLICATION
Recent development era in technology has huge requirement of high performance lightweight, and compact heat transfer equipment. To accomplish this demand fins are widely used as effective elements for heat transfer enhancement. One of the commonly used heat exchanger fins is the pin fin which offers an economical and trouble free solution in many situations. This is more important in cooling of air conditioning equipment, thermal power plants, gas turbine blade, aerospace industry, combustion chamber liners, and biomedical devices, electrical and electronic component. Therefore now a day’s industries are utilizing thermal system with pin fins and analyse the various influencing parameters on performance of pin fin of different geometry under force convection. The turbulence occurred due to these techniques are good enough to enhance heat transfer rate. This article is focused on comprehensive review of work carried out in this technology.
Analysis of Natural Convention Heat Transfer Enhancement in Finned Tube Heat ...journal ijrtem
ABSTRACT: Most of the engineering problems require high performance heat transfer components with progressively less weight, volumes, accommodating shapes and costs. Air cooled heat exchangers are subjected to air on outer side of heat exchanger surface on in heat recovery systems like economizers gases are subjected on one side of tube surface. On air or gas side heat transfer coefficient is less. Extended surface (fins) are one of the next exchanging devices that are employed extensively to increase heat transfer rates from tubular heat exchangers. The rate of heat transfer depends on the surface area of fin available for exchanging the heat transfer rate from the primary surface of cylindrical shape. Present study focuses on enhancement of heat transfer by using both circular and elliptical type of fins. The present paper attempts to examine trend of heat transfer coefficient experimentally and by using CFD software for various types of elliptical fins with i) varying elliptical ratio, ii) changing orientation of mounting of heat exchanger tube with elliptical fins, iii) varying spacing or fin density. KEY WORDS: Natural convection, Heat transfer enhancements, Elliptical fin, Fin orientation, Fin density.
Heat exchangers are used widely in industrial application such as chemical,
food processing, power production, refrigeration and air-conditioning
industries. Helical coiled heat exchangers are used in order to obtain a large
heat transfer per unit volume and to enhance the heat transfer rate on the inside
surface. In the present study, CFD simulations are carried out for a counter
flow tube in tube helical heat exchanger where hot water flows through the
inner tube and cold water flows through the outer tube. From the simulation
results heat transfer coefficient, pressure drop and nusselt number are
calculated. The heat transfer characteristics of the same are compared with that
of a counter flow tube in tube straight tube heat exchanger of same length
under same temperature and flow conditions. CFD simulation results showed
that the helical tube in tube heat exchanger is more effective than the straight
tube in tube heat exchanger.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Analysis of Coiled-Tube Heat Exchangers to Improve Heat Transfer Rate With Sp...IJMER
Steady heat transfer enhancement has been studied in helically coiled-tube heat exchangers. The outer side of the wall of the heat exchanger contains a helical corrugation which makes a helical rib on the inner side of the tube wall to induce additional swirling motion of fluid particles. Numerical calculations have been carried out to examine different geometrical parameters and the impact of flow and thermal boundary conditions for the heat transfer rate in laminar and transitional flow regimes. Calculated results have been compared to existing empirical formula and experimental tests to investigate the validity of the numerical results in case of common helical tube heat exchanger and additionally results of the numerical computation of corrugated straight tubes for laminar and transition flow have been validated with experimental tests available in the literature. Comparison of the flow and temperature fields in case of common helical tube and the coil with spirally corrugated wall configuration are discussed. Heat exchanger coils with helically corrugated wall configuration show 80–100% increase for the inner side heat transfer rate due to the additionally developed swirling motion while the relative pressure drop is 10–600% larger compared to the common helically coiled heat exchangers. New empirical Co-relation has been proposed for the fully developed inner side heat transfer prediction in case of helically corrugated wall configuration.
experimental investigation of heat transfer intensification of pin fins under...INFOGAIN PUBLICATION
Recent development era in technology has huge requirement of high performance lightweight, and compact heat transfer equipment. To accomplish this demand fins are widely used as effective elements for heat transfer enhancement. One of the commonly used heat exchanger fins is the pin fin which offers an economical and trouble free solution in many situations. This is more important in cooling of air conditioning equipment, thermal power plants, gas turbine blade, aerospace industry, combustion chamber liners, and biomedical devices, electrical and electronic component. Therefore now a day’s industries are utilizing thermal system with pin fins and analyse the various influencing parameters on performance of pin fin of different geometry under force convection. The turbulence occurred due to these techniques are good enough to enhance heat transfer rate. This article is focused on comprehensive review of work carried out in this technology.
Analysis of Natural Convention Heat Transfer Enhancement in Finned Tube Heat ...journal ijrtem
ABSTRACT: Most of the engineering problems require high performance heat transfer components with progressively less weight, volumes, accommodating shapes and costs. Air cooled heat exchangers are subjected to air on outer side of heat exchanger surface on in heat recovery systems like economizers gases are subjected on one side of tube surface. On air or gas side heat transfer coefficient is less. Extended surface (fins) are one of the next exchanging devices that are employed extensively to increase heat transfer rates from tubular heat exchangers. The rate of heat transfer depends on the surface area of fin available for exchanging the heat transfer rate from the primary surface of cylindrical shape. Present study focuses on enhancement of heat transfer by using both circular and elliptical type of fins. The present paper attempts to examine trend of heat transfer coefficient experimentally and by using CFD software for various types of elliptical fins with i) varying elliptical ratio, ii) changing orientation of mounting of heat exchanger tube with elliptical fins, iii) varying spacing or fin density. KEY WORDS: Natural convection, Heat transfer enhancements, Elliptical fin, Fin orientation, Fin density.
Heat exchangers are used widely in industrial application such as chemical,
food processing, power production, refrigeration and air-conditioning
industries. Helical coiled heat exchangers are used in order to obtain a large
heat transfer per unit volume and to enhance the heat transfer rate on the inside
surface. In the present study, CFD simulations are carried out for a counter
flow tube in tube helical heat exchanger where hot water flows through the
inner tube and cold water flows through the outer tube. From the simulation
results heat transfer coefficient, pressure drop and nusselt number are
calculated. The heat transfer characteristics of the same are compared with that
of a counter flow tube in tube straight tube heat exchanger of same length
under same temperature and flow conditions. CFD simulation results showed
that the helical tube in tube heat exchanger is more effective than the straight
tube in tube heat exchanger.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
FLUID FLOW ANALYSIS IN AIR DUCT FLOW WITH AND WITHOUT INTERNAL THREADS USING ...IAEME Publication
Computational heat transfer flow modeling is one of the great challenges in the classical sciences. As with most problems in engineering, the interest in the heat transfer augmentation is increasing due to its extreme importance in various industrial applications. This paper deals with the analysis of heat transfer for fluid flowing through the pipe with and without internal threads using CFD. Using CFD codes for modeling the heat and fluid flow is an efficient tool for predicting equipment performance. CFD offers a convenient means to study the detailed flows and heat exchange processes, which take place inside the tube. Simulations were carried out using commercial CFD software ANSYS Fluent version 14.5. Friction factor and Nusselt number for air flowing through the specified tube (internal diameter = 0.005 m, length = 0.1 m) were obtained first for the plain tube and then for the tube with internal threads with pitch 5mm in the Reynolds number range of 2000 to 5000. Finally results will be compared to available experimental and analytical calculations. The data obtained by simulation are matching with the literature value for a plain tube with the discrepancy of less than plus or minus 5% for Nusselt number and for the friction factor.
Enhanced heat transfer for the tube with internal threads has been observed. Heat flux is more uniform all along the tube and decreases uniformly towards the center.
Comparison of Shell and Tube Heat Exchanger using Theoretical Methods, HTRI, ...IJERA Editor
The aim of this article is to compare the design of Shell and Tube Heat Exchanger with baffles. Baffles used in
shell and tube heat exchanger improve heat transfer and also result in increased pressure drop. Shell and tube
heat exchanger with single segmental baffles was designed with same input parameters using 1) Kern’s
theoretical method; 2) ASPEN simulation software and 3) HTRI simulation software 4) SOLIDWORKS
simulation software. Shell side pressure drop and heat transfer coefficient are predicted. The results of all the
three methods indicated the results in a close range. The proven theoretical methods are in good agreement with
the simulation results
Comparative Study and Analysis between Helical Coil and Straight Tube Heat Ex...IJERA Editor
The purpose of this study is to determine the relative advantage of using a helically coiled heat exchanger against a straight tube heat exchanger. It is found that the heat transfer in helical circular tubes is higher as compared to Straight tube due to their shape. Helical coils offer advantageous over straight tubes due to their compactness and increased heat transfer coefficient. The increased heat transfer coefficients are a consequence of the curvature of the coil, which induces centrifugal forces to act on the moving fluid, resulting in the development of secondary flow. The curvature of the coil governs the centrifugal force while the pitch (or helix angle) influences the torsion to which the fluid is subjected to the centrifugal force results in the development of secondary flow. Due to the curvature effect, the fluid streams in the outer side of the pipe moves faster than the fluid streams in the inner side of the pipe. In current work the fluid to fluid heat exchange is taken into consideration. Most of the investigations on heat transfer coefficients are for constant wall temperature or constant heat flux. The effectiveness, overall heat transfer coefficient, effect of cold water flow rate on effectiveness of heat exchanger when hot water mass flow rate is kept constant and effect of hot water flow rate on effectiveness when cold water flow rate kept constant studied and compared for parallel flow, counter flow arrangement of Helical coil and Straight tube heat exchangers. All readings were taken at steady state condition of heat exchanger. The result shows that the heat transfer coefficient is affected by the geometry of the heat exchanger. Helical coil heat exchanger are superior in all aspect studied here.
CFD Analysis of Concentric Tube Heat Exchanger Using Twisted TapesIJARIIT
In this paper, the three dimensional CFD modeling studies on heat transfer, friction factor and thermal performance
of concentric tube heat exchanger using twisted tapes (Plain, V-cut, , Jagged V-cut) with different twist ratios (y=2.0, 4.0) are
used. Twisted tapes are used to augment the heat transfer by creating turbulence in the fluid flow. Various methods are applied
to increase thermal performance of heat transfer devices such as treated surfaces, rough surfaces, swirling flow devices, coiled
tubes, and surface tension devices. Out of these twisted tape method is used to increase the thermal performance. Twisted tape
inserts on effectiveness of heat exchanger has analyzed for different Reynolds Number. The maximum thermal performance
factor was obtained by the Jagged V-cut twisted tape (H=50) insert compare to other twisted tapes. Simultaneously the friction
factor has been analyzed
EXPERIMENTAL STUDY ON THE ANALYSIS OF HEAT ENHANCEMENT IN CORRUGATED TWISTED ...P singh
In heat exchanger, the enthalpy is transferred between two or more fluids, at different temperatures. The major challenge in designing a heat exchanger is to make the equipment more compact and achieve a high heat transfer rate using minimum pumping power. In recent years, the high cost of energy and material has resulted in an increased effort aimed at producing more efficient heat exchange equipment. Furthermore, as a heat exchanger becomes older, the resistance to heat transfer increases owing to fouling or scaling. The heat transfer rate can be improved by introducing a disturbance in the fluid flow thereby breaking the viscous and thermal boundary layer. However, in the process pumping power may increase significantly and ultimately the pumping cost becomes high. Therefore, to achieve a desired heat transfer rate in an existing heat exchanger at an economic pumping power, several techniques have been proposed in recent years and are discussed under the classification section.
In this work, a study of transient heat transfer in double tube heat exchanger has enhanced. The inner tube of the setup was made with corrugation on both inner and outer walls by twisting the pipe from one end, which gives the more swirling motion to the fluid particles flowing over it. The flow inside the pipe was considered as turbulent, and the analysis was done experimentally and theoretically by using the ANSYS workbench. The experimental results were compared with the experimental values taken in the setup done by considering the inner tube as normal pipe. In both heat exchangers the values were taken and compared with the theoretical analysis. Temperature distribution and heat transfer rate were calculated and the details of the study have been discussed in this paper.
Comparative Study of ECONOMISER Using the CFD Analysis IJMER
This paper presents a simulation of the economizer zone, which allowsstudying the flow
patterns developed in the fluid, while it flows along the length of the economizer. The past failure
details revelsthat erosion is more in U-bend areas of Economizer Unit because of increase in flue gas
velocity near these bends. But it isobserved that the velocity of flue gases surprisingly increases near
the lower bends as compared to upper ones. The model issolved using conventional CFD techniques by
FLUENT software. In which the individual tubes are treated as sub-gridfeatures. A geometrical model
is used to describe the multiplicity of heat-exchanging structures and the interconnectionsamong them.
The Computational Fluid Dynamics (CFD) approach is utilised for the creation of a three-dimensional
modelof the economizer coil of single column tube. With equilibrium assumption applied for
description of the system chemistry. The flue gastemperature, pressure and velocity field of fluid flow
within an economizer tube using the actual bounda
Experimental Study of Heat Transfer Enhancement of Pipe-inPipe Helical Coil H...iosrjce
Heat transfer enhancement in pipe in pipe helical coils has been research by many researchers.
While the many literatures available on heat transfer characteristics of helical coil heat exchangers. There is
very few published on validate experimental results through Computational Fluid Dynamics. This paper focuses
on experimental investigation of fluid-to-fluid heat transfer enhancement of pipe-in-pipe helical coil tubes. The
methodology of experimental analysis of a helical tubes heat exchanger, the effect of the inside tubes at constant
value of mass flow rate in Dean Number and also established the surface heat transfer coefficient. Heat transfer
characteristics inside pipe-in-pipe helical coils for various boundary conditions, that the specification of a
constant temperature at hot water inlet, constant mass flow rate. Hence, the pipe-in-pipe heat exchanger is
considering different mass flow rate inside and annulus. The fabrication of experimental setup is estimate the
heat transfer enhancement in inside helical coil tubes
A Review on Study of Heat Transfer Analysis of Helical Coil Heat Exchangersijtsrd
Now a day’s a geometrically modified Helical coil heat exchangers are widely using in industrial applications like cryogenic state processes, air conditioning, thermal nuclear reactors and waste heat recovery due to their compact size and high heat transfer coefficient. Advantage of using helical coils over straight tubes is that the residence time spread is reduced, allowing helical coils to be used to reduce axial dispersion in tubular reactors. In this study, numerical investigation of the influence of geometrical parameters such as tube diameter d , coil radius R , and coil pitch p on overall heat transfer coefficient in helical double tube heat exchangers are performed using a professional CFD software FLUENT. In recent years, numerous styles were introduced for heat exchangers that apply to completely different applications sadly, their heat transfer co efficient wasnt reliable at different operational conditions. the standard of the heat changed rate wasnt optimized and there have been many deficiencies and errors in styles. The heat transfer of the copper material is enhanced in comparison with other material unfortunately thermal resistance is reduced with an increase in pressure drop thus enhancing the heat transfer on the heat exchanger. Helical architecture is often designed with a clear motive of compact size and also address heat transfer co efficient and other ancillary attributes efficiently and effectively. So the better material is suggested for an industrial heat exchanger according to the applications is Copper with the basis of simulation results. The geometry and different dimension parameter of the helical coil show that the proposed study in different material properties and different mass flow rates to heat transfer are maximum in different parameter helical coil heat exchangers. Finally, the heat transfer increase for the copper material compared to another material but with the increase in pressure drop the corresponding thermal resistance decreases which allow the improved heat transfer rate and the rate increases from Aluminum to Bronze to Copper. With the drop in temperature, the thermal resistance is reduced which enhances the heat transfer rate. The simulation results show that the copper has a high heat transfer coefficient than Aluminum and Bronze while operating in identical conditions. Due to the extensive use of helical coils in various applications, knowledge about the flow patterns and heat transfer characteristics are important. Atul Vats | Sunil Kumar Chaturvedi | Abhishek Bhandari "A Review on Study of Heat Transfer Analysis of Helical Coil Heat Exchangers" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-4 , June 2021, URL: https://www.ijtsrd.compapers/ijtsrd43650.pdf Paper URL: https://www.ijtsrd.comengineering/mechanical-engineering/43650/a-review-on-study-of-heat-transfer-analysis-of-helical-coil-heat-exchangers/atul-vats
In compact heat exchangers, thermal resistance is generally dominant on the air-side and may
account for 80% or more of the total thermal resistance. The air-side heat transfer surface area is 8 to
10 times larger than the water-side. Any improvement in the heat transfer on air-side therefore
improves the overall performance of the heat exchanger. Due to the high thermal resistance on the
air-side, the optimization of such fins is essential to increase the performance of the heat exchangers
which results in thermal systems enhancement. This helps to reduce CO2 emissions through a
reduction of mass and fuel consumption.
Optimization of louvered fin geometry in such heat exchangers is essential to increase the
heat transfer performance and reduce weight, packaging, and cost requirements. In this study deals
with Computational Fluid Dynamics (CFD) studies of the interactions between the air flow and
louvered fins which equipped the automotive heat exchangers is carried out. 3D numerical
simulation results is obtained by using the ANSYS Fluent 14.0 code and compared with
experimental data. Finally the effect of louver angle and louver pitch geometrical parameters, on
overall thermal hydraulic performances of louvered fins is studied.
The heat transfer duty or thermal performance of heat exchangers can be improved by heat transfer
enhancement techniques. Coiled wire insert has been used as one of the passive heat transfer enhancement
techniques and are the most widely used tubes in several heat transfer applications, for example, heat recovery
processes, air conditioning and refrigeration systems, chemical reactors, food and dairy processes, Thermal
Power plants, radiators for space vehicles, automobiles etc. These techniques broadly are of three types viz.
passive, active and compound techniques. The present paper is a review of the passive augmentation techniques
used in the recent past.
FLUID FLOW ANALYSIS IN AIR DUCT FLOW WITH AND WITHOUT INTERNAL THREADS USING ...IAEME Publication
Computational heat transfer flow modeling is one of the great challenges in the classical sciences. As with most problems in engineering, the interest in the heat transfer augmentation is increasing due to its extreme importance in various industrial applications. This paper deals with the analysis of heat transfer for fluid flowing through the pipe with and without internal threads using CFD. Using CFD codes for modeling the heat and fluid flow is an efficient tool for predicting equipment performance. CFD offers a convenient means to study the detailed flows and heat exchange processes, which take place inside the tube. Simulations were carried out using commercial CFD software ANSYS Fluent version 14.5. Friction factor and Nusselt number for air flowing through the specified tube (internal diameter = 0.005 m, length = 0.1 m) were obtained first for the plain tube and then for the tube with internal threads with pitch 5mm in the Reynolds number range of 2000 to 5000. Finally results will be compared to available experimental and analytical calculations. The data obtained by simulation are matching with the literature value for a plain tube with the discrepancy of less than plus or minus 5% for Nusselt number and for the friction factor.
Enhanced heat transfer for the tube with internal threads has been observed. Heat flux is more uniform all along the tube and decreases uniformly towards the center.
Comparison of Shell and Tube Heat Exchanger using Theoretical Methods, HTRI, ...IJERA Editor
The aim of this article is to compare the design of Shell and Tube Heat Exchanger with baffles. Baffles used in
shell and tube heat exchanger improve heat transfer and also result in increased pressure drop. Shell and tube
heat exchanger with single segmental baffles was designed with same input parameters using 1) Kern’s
theoretical method; 2) ASPEN simulation software and 3) HTRI simulation software 4) SOLIDWORKS
simulation software. Shell side pressure drop and heat transfer coefficient are predicted. The results of all the
three methods indicated the results in a close range. The proven theoretical methods are in good agreement with
the simulation results
Comparative Study and Analysis between Helical Coil and Straight Tube Heat Ex...IJERA Editor
The purpose of this study is to determine the relative advantage of using a helically coiled heat exchanger against a straight tube heat exchanger. It is found that the heat transfer in helical circular tubes is higher as compared to Straight tube due to their shape. Helical coils offer advantageous over straight tubes due to their compactness and increased heat transfer coefficient. The increased heat transfer coefficients are a consequence of the curvature of the coil, which induces centrifugal forces to act on the moving fluid, resulting in the development of secondary flow. The curvature of the coil governs the centrifugal force while the pitch (or helix angle) influences the torsion to which the fluid is subjected to the centrifugal force results in the development of secondary flow. Due to the curvature effect, the fluid streams in the outer side of the pipe moves faster than the fluid streams in the inner side of the pipe. In current work the fluid to fluid heat exchange is taken into consideration. Most of the investigations on heat transfer coefficients are for constant wall temperature or constant heat flux. The effectiveness, overall heat transfer coefficient, effect of cold water flow rate on effectiveness of heat exchanger when hot water mass flow rate is kept constant and effect of hot water flow rate on effectiveness when cold water flow rate kept constant studied and compared for parallel flow, counter flow arrangement of Helical coil and Straight tube heat exchangers. All readings were taken at steady state condition of heat exchanger. The result shows that the heat transfer coefficient is affected by the geometry of the heat exchanger. Helical coil heat exchanger are superior in all aspect studied here.
CFD Analysis of Concentric Tube Heat Exchanger Using Twisted TapesIJARIIT
In this paper, the three dimensional CFD modeling studies on heat transfer, friction factor and thermal performance
of concentric tube heat exchanger using twisted tapes (Plain, V-cut, , Jagged V-cut) with different twist ratios (y=2.0, 4.0) are
used. Twisted tapes are used to augment the heat transfer by creating turbulence in the fluid flow. Various methods are applied
to increase thermal performance of heat transfer devices such as treated surfaces, rough surfaces, swirling flow devices, coiled
tubes, and surface tension devices. Out of these twisted tape method is used to increase the thermal performance. Twisted tape
inserts on effectiveness of heat exchanger has analyzed for different Reynolds Number. The maximum thermal performance
factor was obtained by the Jagged V-cut twisted tape (H=50) insert compare to other twisted tapes. Simultaneously the friction
factor has been analyzed
EXPERIMENTAL STUDY ON THE ANALYSIS OF HEAT ENHANCEMENT IN CORRUGATED TWISTED ...P singh
In heat exchanger, the enthalpy is transferred between two or more fluids, at different temperatures. The major challenge in designing a heat exchanger is to make the equipment more compact and achieve a high heat transfer rate using minimum pumping power. In recent years, the high cost of energy and material has resulted in an increased effort aimed at producing more efficient heat exchange equipment. Furthermore, as a heat exchanger becomes older, the resistance to heat transfer increases owing to fouling or scaling. The heat transfer rate can be improved by introducing a disturbance in the fluid flow thereby breaking the viscous and thermal boundary layer. However, in the process pumping power may increase significantly and ultimately the pumping cost becomes high. Therefore, to achieve a desired heat transfer rate in an existing heat exchanger at an economic pumping power, several techniques have been proposed in recent years and are discussed under the classification section.
In this work, a study of transient heat transfer in double tube heat exchanger has enhanced. The inner tube of the setup was made with corrugation on both inner and outer walls by twisting the pipe from one end, which gives the more swirling motion to the fluid particles flowing over it. The flow inside the pipe was considered as turbulent, and the analysis was done experimentally and theoretically by using the ANSYS workbench. The experimental results were compared with the experimental values taken in the setup done by considering the inner tube as normal pipe. In both heat exchangers the values were taken and compared with the theoretical analysis. Temperature distribution and heat transfer rate were calculated and the details of the study have been discussed in this paper.
Comparative Study of ECONOMISER Using the CFD Analysis IJMER
This paper presents a simulation of the economizer zone, which allowsstudying the flow
patterns developed in the fluid, while it flows along the length of the economizer. The past failure
details revelsthat erosion is more in U-bend areas of Economizer Unit because of increase in flue gas
velocity near these bends. But it isobserved that the velocity of flue gases surprisingly increases near
the lower bends as compared to upper ones. The model issolved using conventional CFD techniques by
FLUENT software. In which the individual tubes are treated as sub-gridfeatures. A geometrical model
is used to describe the multiplicity of heat-exchanging structures and the interconnectionsamong them.
The Computational Fluid Dynamics (CFD) approach is utilised for the creation of a three-dimensional
modelof the economizer coil of single column tube. With equilibrium assumption applied for
description of the system chemistry. The flue gastemperature, pressure and velocity field of fluid flow
within an economizer tube using the actual bounda
Experimental Study of Heat Transfer Enhancement of Pipe-inPipe Helical Coil H...iosrjce
Heat transfer enhancement in pipe in pipe helical coils has been research by many researchers.
While the many literatures available on heat transfer characteristics of helical coil heat exchangers. There is
very few published on validate experimental results through Computational Fluid Dynamics. This paper focuses
on experimental investigation of fluid-to-fluid heat transfer enhancement of pipe-in-pipe helical coil tubes. The
methodology of experimental analysis of a helical tubes heat exchanger, the effect of the inside tubes at constant
value of mass flow rate in Dean Number and also established the surface heat transfer coefficient. Heat transfer
characteristics inside pipe-in-pipe helical coils for various boundary conditions, that the specification of a
constant temperature at hot water inlet, constant mass flow rate. Hence, the pipe-in-pipe heat exchanger is
considering different mass flow rate inside and annulus. The fabrication of experimental setup is estimate the
heat transfer enhancement in inside helical coil tubes
A Review on Study of Heat Transfer Analysis of Helical Coil Heat Exchangersijtsrd
Now a day’s a geometrically modified Helical coil heat exchangers are widely using in industrial applications like cryogenic state processes, air conditioning, thermal nuclear reactors and waste heat recovery due to their compact size and high heat transfer coefficient. Advantage of using helical coils over straight tubes is that the residence time spread is reduced, allowing helical coils to be used to reduce axial dispersion in tubular reactors. In this study, numerical investigation of the influence of geometrical parameters such as tube diameter d , coil radius R , and coil pitch p on overall heat transfer coefficient in helical double tube heat exchangers are performed using a professional CFD software FLUENT. In recent years, numerous styles were introduced for heat exchangers that apply to completely different applications sadly, their heat transfer co efficient wasnt reliable at different operational conditions. the standard of the heat changed rate wasnt optimized and there have been many deficiencies and errors in styles. The heat transfer of the copper material is enhanced in comparison with other material unfortunately thermal resistance is reduced with an increase in pressure drop thus enhancing the heat transfer on the heat exchanger. Helical architecture is often designed with a clear motive of compact size and also address heat transfer co efficient and other ancillary attributes efficiently and effectively. So the better material is suggested for an industrial heat exchanger according to the applications is Copper with the basis of simulation results. The geometry and different dimension parameter of the helical coil show that the proposed study in different material properties and different mass flow rates to heat transfer are maximum in different parameter helical coil heat exchangers. Finally, the heat transfer increase for the copper material compared to another material but with the increase in pressure drop the corresponding thermal resistance decreases which allow the improved heat transfer rate and the rate increases from Aluminum to Bronze to Copper. With the drop in temperature, the thermal resistance is reduced which enhances the heat transfer rate. The simulation results show that the copper has a high heat transfer coefficient than Aluminum and Bronze while operating in identical conditions. Due to the extensive use of helical coils in various applications, knowledge about the flow patterns and heat transfer characteristics are important. Atul Vats | Sunil Kumar Chaturvedi | Abhishek Bhandari "A Review on Study of Heat Transfer Analysis of Helical Coil Heat Exchangers" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-4 , June 2021, URL: https://www.ijtsrd.compapers/ijtsrd43650.pdf Paper URL: https://www.ijtsrd.comengineering/mechanical-engineering/43650/a-review-on-study-of-heat-transfer-analysis-of-helical-coil-heat-exchangers/atul-vats
In compact heat exchangers, thermal resistance is generally dominant on the air-side and may
account for 80% or more of the total thermal resistance. The air-side heat transfer surface area is 8 to
10 times larger than the water-side. Any improvement in the heat transfer on air-side therefore
improves the overall performance of the heat exchanger. Due to the high thermal resistance on the
air-side, the optimization of such fins is essential to increase the performance of the heat exchangers
which results in thermal systems enhancement. This helps to reduce CO2 emissions through a
reduction of mass and fuel consumption.
Optimization of louvered fin geometry in such heat exchangers is essential to increase the
heat transfer performance and reduce weight, packaging, and cost requirements. In this study deals
with Computational Fluid Dynamics (CFD) studies of the interactions between the air flow and
louvered fins which equipped the automotive heat exchangers is carried out. 3D numerical
simulation results is obtained by using the ANSYS Fluent 14.0 code and compared with
experimental data. Finally the effect of louver angle and louver pitch geometrical parameters, on
overall thermal hydraulic performances of louvered fins is studied.
The heat transfer duty or thermal performance of heat exchangers can be improved by heat transfer
enhancement techniques. Coiled wire insert has been used as one of the passive heat transfer enhancement
techniques and are the most widely used tubes in several heat transfer applications, for example, heat recovery
processes, air conditioning and refrigeration systems, chemical reactors, food and dairy processes, Thermal
Power plants, radiators for space vehicles, automobiles etc. These techniques broadly are of three types viz.
passive, active and compound techniques. The present paper is a review of the passive augmentation techniques
used in the recent past.
CFD Analysis of Plate Fin Tube Heat Exchanger for Various Fin InclinationsIJERA Editor
ANSYS Fluent software is used for three dimensional CFD simulations to investigate heat transfer and fluid flow characteristics of six different fin angles with plain fin tube heat exchangers. The numerical simulation of the fin tube heat exchanger was performed by using a three dimensional numerical computation technique. Geometry of model is created and meshed by using ANSYS Workbench software. To solve the equation for the fluid flow and heat transfer analysis ANSYS FLUENT was used in the fin-tube heat exchanger. The fluid flow and heat transfer are simulated and result compared for both laminar and turbulent flow models k-epsilon and SST k-omega, with steady state solvers to calculate heat transfer, flow velocity and temperature fields of variable inclined fin angles (Ɵ = 00,100 , 200, 300, 400,500). Model is validate by comparing the simulated value of velocity, temperature and colburn factor with experimental and numerical results investigated by WANG [1] and GHORI KIRAR [10]. Reasonable agreement is found between the simulations and other results, and the ANSYS Fluent software is sufficient for simulating the flow fields in tube fin heat exchanger.
Heat transfer enhancement_fusion reactor.pdfSandeepRimza1
jet impingement technique with a sectorial extended surface (SES) concept for the modular heliumcooled
divertor has been studied within the framework of the post ITER tokamak, at the Institute for
plasma research (IPR), INDIA. Experimental and numerical studies have been conducted to predict the
thermal-hydraulic performance of a finger-type divertor design with proposed SES. Critical thermal
hydraulic parameters, effective heat transfer coefficient and pressure loss have been measured in the
experiment for the reference divertor as well as for a divertor with SES. The experimental mock-ups are
made to full scale respecting Reynolds and Prandtl number similarities. Air is used as the simulant to
represent helium, which is used as the coolant in prototype. A novel heat concentrator has been
developed to simulate the high heat flux, by electrical heating.
Biodiesel, Brake thermal efficiency, Brake specific fuel consumption Honge, J...IJMER
Steady heat transfer enhancement has been studied in helically coiled-tube heat exchangers. The outer side of the wall of the heat exchanger contains a helical corrugation which makes a helical rib on the inner side of the tube wall to induce additional swirling motion of fluid particles. Numerical calculations have been carried out to examine different geometrical parameters and the impact of flow and thermal boundary conditions for the heat transfer rate in laminar and transitional flow regimes. Calculated results have been compared to existing empirical formula and experimental tests to investigate the validity of the numerical results in case of common helical tube heat exchanger and additionally results of the numerical computation of corrugated straight tubes for laminar and transition flow have been validated with experimental tests available in the literature. Comparison of the flow and temperature fields in case of common helical tube and the coil with spirally corrugated wall configuration are discussed. Heat exchanger coils with helically corrugated wall configuration show 80–100% increase for the inner side heat transfer rate due to the additionally developed swirling motion while the relative pressure drop is 10–600% larger compared to the common helically coiled heat exchangers. New empirical Co-relation has been proposed for the fully developed inner side heat transfer prediction in case of helically corrugated wall configuration.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Numerical Analysis of Header Configuration of the Plate-Fin Heat ExchangerIJMER
Numerical analysis of a plate fin heat exchanger accounting for the effect of fluid flow
maldistribution onthe inlet header configuration of the heat exchanger is investigated. In this analysis , it
was found that flow maldistribution has effect on the flow perpendicular to its velocity direction. The peak
velocity occurs in the central zone of the header while the velocityalong the perpendicular direction of the
inlet flow diminishes more and more. By this investigation,the results of the flow maldistribution are
presented for a plate fin heat exchangerwhich is reduced as compare to theexisting configuration of the
plate fin heat exchanger.
CFD Analysis for Heat Transfer Enhancement of a Corrugated Plate Heat Exchang...ijtsrd
The flow properties of heat transfer across such corrugated channels are very distinct from parallel plate channels. The primary flow direction is parallel to the waviness of the channel of the corrugated channel, although the local flow direction is still changed due to the waviness of the channel. By flow recirculation, separation and re attachment, the thermal boundary layer formed on its walls is regularly disrupted and the convective heat transfer coefficient is thus increased. In this work, in corrugated channels, the convective heat transfer and pressure drop characteristics of flow have been tested numerically. On channels of uniform heat flux and fixed corrugation over a Reynolds number spectrum, 10000 = Re = 30000, numerical research was conducted. The impacts of channel configuration, variation in Reynold’s number, and concentration variations of nanoparticles in base fluid on heat transfer are discussed. As opposed to the traditional corrugated channel, a major heat transfer gain was associated with the proposed corrugated channel. Based on the nanofluid concentration, Reynold number and channel configuration of the corrugated channel, the average Nusselt number increased by a factor of 2.2 up to 2.8 compared to that of the semi circular corrugated channel. Compared with the effect of channel configuration variation, triangular corrugated channel was the best Nusselt numbers, followed by the shape Semi circular Triangular , and Semi circular corrugated channel with the lowest results. Prof. Pushparaj Singh | Rishi Kesh Jha "CFD Analysis for Heat Transfer Enhancement of a Corrugated Plate Heat Exchanger using Different Corrugated Channel Configurations" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-4 | Issue-6 , October 2020, URL: https://www.ijtsrd.com/papers/ijtsrd35706.pdf Paper Url: https://www.ijtsrd.com/engineering/mechanical-engineering/35706/cfd-analysis-for-heat-transfer-enhancement-of-a-corrugated-plate-heat-exchanger-using-different-corrugated-channel-configurations/prof-pushparaj-singh
Numerical Investigation of Heat Transfer from Two Different Cylinders in Tand...IJERA Editor
A two dimensional technique has been studied numerically to predict the heat transfer from two different cylinders
in tandem arrangement (one is circular and the other is elliptical) using finite element technique with RNG k-ε turbulent
model, taking into consideration the effect of gap ratio (L/Deq ) and Reynolds number , where the distance between
the centers of cylinders is L (L=30 mm and 37 mm), the equivalent diameter of cylinder is Deq=22.5mm and
the range of Reynolds number is 2x103
< Reeq < 21x103 .The commercial CFD software FLUENT was used to get
the thermofluid characteristics (temperature, velocity, kinetic energy and pressure contours ,coefficient of friction ,
heat transfer coefficient , Stanton number …… etc) of the flow around cylinders. The dependency of the heat transfer
coefficient, Stanton number (Sta), pressure drop, and friction factor for circular and elliptical cylinders on the gap
ratio is clear from the results. Results show that, for circular cross section, the heat transfer coefficient is increased as
velocity, and gap ratio increase. On the other hand Sta decreased as velocity increase. The pressure drop and hence
the friction factor increase for circular cylinder as gap ratio increases. For elliptical tube the heat transfer and Sta are
relatively equal to that for circular one at the same gap ratio, but the overall power consumption and friction factor
for elliptical tube is lower than that of circular one. As the elliptical cylinder fixed on the second position the heat
transfer and Sta
increase, on the other hand the pressure drop and hence the friction factor decreases. For all studied
arrangements the highest heat transfer is observed for the arrangement of circular-first and elliptical-second cylinder
and the minimum pressure drop and hence the friction factor are for the elliptical one
THE EFFECT OF GEOMETRICAL PARAMETERS ON HEAT TRANSFER AND HYDRO DYNAMICAL CHA...ijmech
Compact size and high heat transfer coefficient of helical coil heat exchangers causes them to have an
important role in various industrial applications. This paper investigate numerically on the influence of
different parameters such as coil radius, coil pitch and diameter of tube on the hydrodynamic and
heat transfer characteristics of helical double tube heat exchangers using the CFD software which is
based on the principles of heat transfer, fluid mechanics and thermodynamics. The results indicated that
heat transfer augmentation occurs by increasing of the inner Dean Number, inner tube diameter, curvature
ratio and by the reduction of the pitch of heat exchanger coil. By increasing the radius of coils, the
secondary flow effects due to centrifugal forces diminishes and flow of fluid through the coils tends to flow
in a straight path and as a result, the friction coefficient decreases consequently.
Experimental Investigation of a Household Refrigerator Using Evaporative-Cool...inventy
The objective of this paper was to investigate experimentally the effect of Evaporative-cooled condenser in a household refrigerator. The experiment was done using HCF134a as the refrigerant. The performance of the household refrigerator with air-cooled and Evaporative-cooled condenser was compared for different load conditions. The results indicate that the refrigerator performance had improved when evaporative-cooled condenser was used instead of air-cooled condenser on all load conditions. Evaporativecooled condenser reduced the energy consumption when compared with the air-cooled condenser. There was also an enhancement in coefficient of performance (COP) when evaporative-cooled condenser was used instead of air-cooled condenser. The Evaporative cooled heat exchanger was designed and the system was modified by retrofitting it, instead of the conventional air-cooled condenser by making drop wise condensation using water and forced circulation over the condenser. From the experimental analysis it is observed that the COP of evaporative cooled system increased by 13.44% compared to that of air cooled system. So the overall efficiency and refrigerating effect is increased. In minimum constructional, maintenance and running cost, the system is much useful for domestic purpose. This study also revealed that combining a evaporative cooled system along with conventional water cooled system under the condition that the defrost water obtained from the freezer is used for drop wise condensation over condenser and water cooled condensation of the condenser at the bottom using remaining defrost water would reduce the power consumption, work done and hence further increase in refrigerating effect of the system. The study has shown that such a system is technically feasible and economically viable
Copper Strip Corrossion Test in Various Aviation Fuelsinventy
This research work takes in to account of corrosiveness test on various aviation fuels in the state of Telengana (India). The purpose of this experiment is to determine the corrosiveness test of fuels. This determination will be accomplished by using copper strip corrosion test by using the copper strip experiment we can determine the corrosive property of the fuel and hence the efficiency of fuel. The research covers the importance of knowing the corrosive property of different petroleum fuels including aviation turbine fuel.
Additional Conservation Laws for Two-Velocity Hydrodynamics Equations with th...inventy
A series of the differential identities connecting velocities, pressure and body force in the twovelocity hydrodynamics equations with equilibrium of pressure phases in reversible hydrodynamic approximation is obtaned.
Comparative Study of the Quality of Life, Quality of Work Life and Organisati...inventy
People’s lives are increasingly centred on work; they spend at least one-third of their time within the organisations that employ them. Investigating the factors that interfere with employees’ well-being and the organisational environment is becoming an increasing concern in organisations. This article identifies the criteria of the quality of life (QoL), quality of working life (QWL) and organisational climate instruments to point out their similarities. For bibliographic construction and data research, articles were sought in national and international journals, books and dissertations/articles in SciELO, Science Direct, Medline and Pub Med databases. The results show direct relationships amongst QoL, QWL and organisational climate instruments. The relationship between QoL and QWL instruments is based on fair compensation, social interaction, organisational communication, working conditions and functional capacity. QWL and organisational climate instruments are related through social interaction and interfaces. QoL and organisational climate instruments are related based on social interaction, organisational communication, and work conditions.
A Study of Automated Decision Making Systemsinventy
The decision making process of many operations are dependent on analysing very large data sets, previous decisions and their results. The information generated from the large data sets are used as an input for making decisions. Since the decisions to be taken in day to day operations are expanding, the time taken for manual decision making is also expanding. In order to reduce the time, cost and to increase the efficiency and accuracy, which are the most important things for customer satisfaction, many organisations are adopting the automated decision making systems. This paper is about the technologies used for automated decision making systems and the areas in which automated decisions systems works more efficiently and accurately.
Crystallization of L-Glutamic Acid: Mechanism of Heterogeneous β -Form Nuclea...inventy
The mechanism of heterogeneous nucleation of β-form L-glutamic acid was deeply investigated in cooling crystallization. The present study found that the β-form crystals were epitaxially grown on the α-form crystals and they were preferably crystallized on the (011) and (001) surfaces instead of the (111) surfaces of α- form crystals. This result was explained via the molecular simulation. The molecular simulation indicated that the different surfaces of α-form crystals provided different functional groups, resulting in different sites for the heterogeneous nucleation of β-form crystals. Here, the functional group were COO- , C=O and O-H on the (011) and (001) surfaces of α-form crystals, respectively, while it was the NH3 + on the (111) surfaces of α-form crystals. As such, the degree of lattice matching (E) between the β-form crystals and the various surfaces of α- form crystal was distinguished, where the degree of lattice matching (E) between the β-form crystals and the (011), (001) and (111) surfaces of α-form crystal were estimated as 5.30, 5.25 and 2.39, respectively, implying that the (011) and (001) surfaces of α-form crystal were more favorable to generate the heterogeneous nucleation of β-form crystals than the (111) surfaces of α-form crystal
Evaluation of Damage by the Reliability of the Traction Test on Polymer Test ...inventy
In recent decades, polymers have undergone a remarkable historical development and their use has been greatly imposed by gradually dethroning most of the secular materials. These polymer materials have always distinguished themselves by their simple shaping and inexpensive price, their versatility, lightness, and chemical stability but despite their massive use in everyday life as well as in advanced technologies. Generally, these materials still not understood which requires a thorough knowledge of their chemical, physical, rheological and mechanical properties. This paper, we study the mechanical behavior of an amorphous polymer: Acrylonitrile Butadiene Styrene “ABS” by means of uniaxial tensile testing on pierced test pieces with different notch lengths ranging between 1 to 14mm.The proposed approach consists in analyzing the evolution of the global geometry of the obtained strain curves by taking into account the zones and characteristic points of these curves as well as the effect of the damage on the mechanical behavior of the polymer ABS, in order to visualize the evolution of the damage by a static model
Application of Kennelly’model of Running Performances to Elite Endurance Runn...inventy
: The model of Kennelly between distance (Dlim) and exhaustion time (tlim) has been applied to the individual performances of 19 elite endurance runners (World-record holders and Olympic winners) from P. Nurmi (1920-1924) to M. Farah (2012) whose individual best performances on several different distances are known. Kennelly’s model (Dlim = k tlim ) can describe the individual performances of elite runners with a high accuracy (errors lower than 2 %). There is a linear relationship between parameters k and exponents of the elite runners and the extreme values correspond to S. Coe (k = 15.8; = 0.851) and E. Zatopek (k = 6.57; = 0.984). Exponent can be considered as a dimensionless index of aerobic endurance which is close to 1 in the best endurance runners. If it is assumed than maximal aerobic speed can be maintained 7 min in elite endurance runners, exponent is equal to the normalized critical speed (critical speed/maximal aerobic speed) computed from exhaustion times equal to 3 and 12.5 min in these runners.
Development and Application of a Failure Monitoring System by Using the Vibra...inventy
In this project, a failure monitoring system is developed by using the vibration and location information of balises in railway signaling. A lot of field equipment in railway are loosening and broken in time period so that they need maintenance due to the vibrations that occur due to high speed trains traffic and railway vehicles impact. Among the field equipment, balises have very important role of communication in terms of transmitting information to trains. In this scope, it is aimed to make maintenance works more efficient, have no delayed trains, detect previously failure location and intervene in failure timely, by detecting and controlling balise cases such as loosening, out of place and the data consistency error that happens because of balise physical state. In this project, the communication is provided with I2C, Modbus RTU (Remote Terminal Unit) and RS485 standards by using Arduino Uno cards and MPU6050 IMU (Inertial Measurement Unit) sensors in laboratory. Each used sensors are in slave mode and computer interface designed with C# is in master mode. Fault situations in the system are checked instant by the interface. (it is assumed to mount the IMU sensor and the Arduino circuit on the balise) it is seen that the interface responds to the sensor movements instant and the system works well in the end of test processes.
The Management of Protected Areas in Serengeti Ecosystem: A Case Study of Iko...inventy
The study assessed the management of protected areas in Serengeti ecosystem using the case of IGGRs. Specifically, the study aimed at identifying the strategies used for natural resources management; examining the impacts of those strategies; examining the hindrances of the identified strategies; and lastly, examining the methods for scaling up the performance of strategies used for natural resources in the study area. The study involved two villages among 31 villages bordering IGGRs where in each village; at least 5% of the households were sampled. Both Primary data and secondary data were collected and analyzed both manually and computer by using SPSS software. The study revealed that, study population ranked IGGRs performance on protection of natural resources, especially on conserving wildlife for future generation and in reducing poaching to be good(53.3%). In addition, the relationship with IGGRs was said to be considerable good (46.7%). In the aspect of reducing poaching, the findings show that poaching has been reduced by 96.2% from 2009 to 2012. Furthermore, 81.4% of respondents said they use different strategies to control loss of natural resources which in turn has considerably improved the relationship between protected areas and the surrounding communities in some of the aspects. Despite of above successes, the study findings has revealed a number of challenges that hinders the full attainment of conservation objectives. Among the challenges are loss of life and properties (86.4%), shortage of water for livestock (68.9%) since water sources such as Grumeti and Rubana rivers are within protected area while the adjacent local communities do not have a free access to those water sources. Other challenges especially on the IGGRs management include insufficient fund base, working facilities and inadequate staffs. Based on the above findings, the study concluded that the strategies used for natural resources management of protected areas in Serengeti ecosystem is fairly sustainable and need functional participatory approaches of local people and other stakeholders in order to bring about a collaborative natural resources management network in the ecosystem. Furthermore, based on the findings above, equity in benefit sharing accrued from natural resource management in protected areas, more financial support to IGGRs and local community, the use of non-lethal deterrents for crop protection, integration of croplivestock production systems, adoption of land use plans as a solution to land conflicts, strengthens of community based conservation (CBC), adoption of modern information technology such as geographical information system (GIS) and remote sensing are recommended.
Size distribution and biometric relationships of little tunny Euthynnus allet...inventy
This study is taken from data of commercial fishing of the little tunny, Euthynnus alletteratus (Rafinesque, 1810) caught in the Algerian coast, sampled between november 2011 and april 2016. Data were collected in order to determine size distributions of the population and biometric relationships of species including the size - weight relationships. A total of 601 fish ranged from 30.9 and 103 cm fork length (FL) were observed. The size distribution of Euthynnus alletteratus shows multiple modal values witch the most important cohort corresponds to the age class 2 (42-46 cm). The value of the allometric coefficient (b) of the FL/TW relationship is lower than 3, indicating a negative allometric growth.
Removal of Chromium (VI) From Aqueous Solutions Using Discarded Solanum Tuber...inventy
Industrial polluting effluents containing heavy metals are of serious environmental concern in India. Chromium is frequently used in industries like electroplating, metal finishing, cooling towers, dyes, paints, anodizing and leather tanning and is found as traces in effluents finding their way to natural water bodies causing hazardous toxicity to the health of humans, animals and aquatic lives directly or indirectly. Many methods for the removal of Chromium such as chemical reduction, precipitation, ion exchange, electrochemical reduction, evaporation, reverse osmosis and adsorption using activated carbon etc. have been reported but all being expensive and complicated to operate. Experimental practices reveal that adsorption by agricultural and horticultural wastes are quite simple, inexpensive and efficient method. Agra is famous for Potato farming, a lot of discarded potato waste from cold storages is thrown along road side drains causing solid waste generated which either creates solid waste disposal problem or otherwise it finds way to Yamuna river resulting high BOD and posing a serious threat to the aquatic environment. For developing countries like India adsorption studies using discarded potato (Solanum tuberosum) waste from cold storages (DPWC) a solid waste as low cost adsorbent for Chromium removal was dual beneficial i.e., an ideal solution to these solid wastes disposal problem of Agra and removal of Chromium from tannery effluents and thereby saving aquatic life from Chromium contamination in Yamuna river. Keeping this in view batch experiments were designed to study the feasibility of discarded potato waste from cold storages to remove chromium (VI) from the aqueous solutions. During the study various affecting parameters, such as pH, adsorbent does, initial concentration, temperature, contact time, adsorbent grain size and start up agitation speed were optimized as 5.0, 10-20 g/l, 50 mg/l, 250C, 135 minutes, average size and 80 rpm respectively on chromium removal efficiency. Various Isotherms such as Langmuir, Freundlich, Tempkin also fitted suitably and various corresponding constants determined from these Isotherms favor and support the adsorption. Thermodynamic constants ∆G, ∆H and ∆S were found to be 0.267 KJ/mole, 0.288 KJ/mole and 0.0013 KJ/mole respectively.
Effect of Various External and Internal Factors on the Carrier Mobility in n-...inventy
The effect of various external (temperature, electric field, light) and intracrystalline (doping, initial resistivity) factors on the mobility of carriers in layered n-InSe semiconductor experimentally have been investigated. Scientific explanations of the results are proposed
Transient flow analysis for horizontal axial upper-wind turbineinventy
This study is to carry out a transient flow field analysis on the condition that the wind turbine is working to generate turbine, the wind turbine operating conditions change over time, Purpose of this study is try to find out the rule from the wind turbine changing over time . In transient analysis, the wind velocity on inlet boundary and rotation speed in the rotor field will change over time, and an analytical process is provided that can be used for future reference. At present, the wind turbine model is designed on the concept of upwind horizontal axis type. The computer engineering software GH Bladed is used to obtain the relationship between the rotor velocity and the wind turbine. Then the ANSYS engineering software is used to calculate the stress and strain distribution in the blades over time. From the analytical result, the relationship between the stress distribution in the blades and the rotor velocity is got to be used as a reference for future wind turbine structural optimization.
Choice of Numerical Integration Method for Wind Time History Analysis of Tall...inventy
Wind tunnel tests are being performed routinely around the world for designing tall buildings but the advent of powerful computational tools will make time-history analysis for wind more common in near future. As the duration of wind storms ranges from tens of minutes to hours while earthquake durations are typically less than a three to four minutes, the choice of a time step size (Δt) for wind studies needs to be much larger both to reduce the computational time and to save disk space. As the error in any numerical solution of the equation of motion is dependent on step size (Δt), careful investigations on the choice of numerical integration methods for wind analyses are necessary. From a wide variety of integration methods available, it was decided to investigate three methods that seem appropriate for 3D-time history analysis of tall buildings for wind. These are modal time history analysis, the Hilber-Hughes-Taylor (HHT) method or α-method with α=- 0.1, and the Newmark method with β=0.25 and γ=0.5 ( i.e., trapezoidal rule). SAP2000, a common structural analysis software tool, and a 64-story structure are used to conduct all the analyses in this paper. A boundary layer wind tunnel (BLWT) pressure time history measured at 120 locations around the building envelope of a similar structure is used for the analyses. Analyses performed with both the HHT and Newmark-method considering P-delta effects show that second order effects have a considerable impact on both displacement and acceleration response. This result shows that it is necessary to account P-delta effect for wind analysis of tall buildings. As the direct integration time history analysis required very large computation times and very large computer physical memory for a wind duration of hours, a modal analysis with reduced stiffness is considered as a good alternative. For that purpose, a non-linear static analysis of the structure with a load combination of 1.0D + 1.0L is performed in SAP2000 and the reduced stiffness of the structure after the analysis is used to conduct an eigenvalue analysis to extract the mode shapes and frequencies of this structure. Then the first 20- modes are used to perform a modal time history analysis for wind load. The result shows that the responses from modal analysis with “20-mode (reduced stiffness)” are comparable with that from the P-Δ analyses of Newmark-method
Impacts of Demand Side Management on System Reliability Evaluationinventy
Electricity demand in Saudi Arabia is steadily increasing as electrical loads grows at a rate of about 7% per year, this represents a high rate by all standards, and largely due to population growth, as well as due to government subsidies which may lead to prices much lower than actual production cost. This growth represents a challenge that requires Saudi Electricity Company (SEC) to invest huge amounts of money every year, for the construction of additional generation capacity along with the reinforcement of transmission network to meet the consumption growth.Also the demand varies frequently throughout the day, causing a waste of a large part of the energy. SEC believes the optimum solution lies in altering the load shape in order to have a better balance between customer’s consumption and SEC’s generation, This paper describes the method for improving the power system reliability by shifting the portion of peak load to off-peak periods This load management scheme can be achieved by lifting the generation during off peak periods and utilizing the stored energy during peak periods. A hybrid set up involving solar and wind energy along with batteries can also be used to store energy and utilize it during peak periods.
Reliability Evaluation of Riyadh System Incorporating Renewable Generationinventy
In this paper, the experience of Saudi Electricity Company (SEC) in analyzing the generation adequacy for Year 2013 is presented. This analysis is conducted by calculating several reliability indices for Riyadh system hourly load during all four seasonal periods. The reliability indices are gauged against the international utility practice. SEC also plans to introduce renewable energy into the network in order to secure the environmental standards and reduce fuel costs of conventional generation. Thus, the reliability improvement due to different integration levels of Solar and Wind generating sources has also been investigated. The capacity value provided by these variable renewable energy sources (VERs) to reliably meet the system load has been calculated using effective load carrying capability (ELCC) technique with a loss of load expectancy metric.
The effect of reduced pressure acetylene plasma treatment on physical charact...inventy
The capacitors are increasingly being used as energy storage devicesin various power systems. The scientists of the world are tryingto maximize the electrical capacity of the supercapacitors. To achieve this purpose, numerous method sare used: the surface activation of electrodes, the surface etching using the electronbeam, the electrode etching with variousgasplasma, etc. The purpose of this work is toresearch how the properties of carbon electrodes depend on the plasma parameters at whichtheywere formed. The largest surface area ofcarbonelectrodeof47.25m2 /gis obtainedat 15 ofAr/C2H2gasratio. Meanwhile, theSEMimages show that the disruption of structures with low bond energies and the formation of new onesare taking place when the carbon electrodes are etched at acetylene plasma and placed on carbon electrode. The measurements of capacitance showthat capacitors with affectedelectrodes have about10-15% highercapacity than those not treated with acetyleneplasma.
Experimental Investigation of Mini Cooler cum Freezerinventy
In general cases the refrigerator could be converted into an air conditioner by attaching a fan. Thus a cooler as well as freezer is obtained in a single set up. The freezer can be converted to an air conditioner when the outside air is allowed to flow beside the cooling coil and is forced outside by an exhaust fan. In this case a mini scale cooler cum freezer using R134a as refrigerant was fabricated and tested In our mini project work we had designed, fabricated and experimentally analysed a mini cooler cum freezer. From the observations and calculations, the results of mini cooler cum freezer are obtained and are compared.
Growth and Magnetic properties of MnGeP2 thin filmsinventy
We have successfully grown MnGeP2 thin films on GaAs (100) substrate. A ferromagnetic transition near 320 K has been observed by temperature dependent magnetization and resistance measurements. Field dependent magnetization experiments have shown that the coercive fields at 5, 250, and 300 K are 3870, 1380 and 155 Oe, respectively. Magnetoresistance and Hall measurements have displayed that hole conduction is dominant in MnGeP2. PACS: 75.50.Pp, 75.70.-i, 85.70.-w, 73.50.-h
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
Vaccine management system project report documentation..pdfKamal Acharya
The Division of Vaccine and Immunization is facing increasing difficulty monitoring vaccines and other commodities distribution once they have been distributed from the national stores. With the introduction of new vaccines, more challenges have been anticipated with this additions posing serious threat to the already over strained vaccine supply chain system in Kenya.
Forklift Classes Overview by Intella PartsIntella Parts
Discover the different forklift classes and their specific applications. Learn how to choose the right forklift for your needs to ensure safety, efficiency, and compliance in your operations.
For more technical information, visit our website https://intellaparts.com
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Event Management System Vb Net Project Report.pdfKamal Acharya
In present era, the scopes of information technology growing with a very fast .We do not see any are untouched from this industry. The scope of information technology has become wider includes: Business and industry. Household Business, Communication, Education, Entertainment, Science, Medicine, Engineering, Distance Learning, Weather Forecasting. Carrier Searching and so on.
My project named “Event Management System” is software that store and maintained all events coordinated in college. It also helpful to print related reports. My project will help to record the events coordinated by faculties with their Name, Event subject, date & details in an efficient & effective ways.
In my system we have to make a system by which a user can record all events coordinated by a particular faculty. In our proposed system some more featured are added which differs it from the existing system such as security.
Student information management system project report ii.pdfKamal Acharya
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1. Research Inventy: International Journal of Engineering And Science
Vol.4, Issue 7 (July 2014), PP 77-85
Issn (e): 2278-4721, Issn (p):2319-6483, www.researchinventy.com
77
Manufacturing and Comparative Analysis of Threaded Tube
Heat Exchanger with Straight Tube Heat Exchanger
Prof.N.B.Totala1
, Prof.V.P.Desai2
, Pratik Gawade3
, Nikhil Kakade4
,Anant
Paralkar5
, ArpitBanerjee6
, Shreenath Agarwal7
1,2
(Assistant Professor, Department of Mechanical Engineering, MIT Academy of Engineering,Alandi (D), Pune,
Maharashtra, 412105)
3,4,5,6
(Department of Mechanical Engineering, MIT Academy of Engineering, Alandi(D), Pune, Maharashtra,
412105)
7
(Assistant Manager, Production G Series, Greaves Cotton Ltd, Diesel Engine Unit, Akurdi.Pune.)
ABSTRACT: To intensify the heat transfer from the heat exchanger surface to fluid, it is possible to increase
convection coefficient, widen temperature difference between surface and fluid or increase the surface area
across which convection occurs. Extended surfaces, in the form of longitudinal or radial fins are common in
applications where the need to enhance the heat transfer between a surface and an adjacent fluid exists. Fins
are commonly used in extended surface exchangers. To minimize the size of heat exchangers, fins are used to
increase the surface area and the heat transfer rate between the heat exchanger surface and the surroundings.
Both the conduction through the fin cross section and the convection over the fin surface area take place in and
around the fin, the temperature value is limited by the type of material and production technique. Due to all
above, finned tube heat exchangers are used in different thermal systems for applications where heat energy is
exchanged between different media. Applications range from very large to the small scale (tubes in heat
exchangers, the temperature control of electronic components).The subject, which is investigated in this paper,
is concentrated on increasing heat transfer rate by provided extended surfaces like threads. By providing
threads, heat transfer area increases and it leads to better heat transfer due to turbulence.
KEYWORDS: Heat transfer co-efficient, Nusselt number, Reynolds number, Thermal conductivity,
I. INTRODUCTION
The performance of a conventional heat exchanger, which is an essential unit in heat extraction and
recovery systems, can be substantially improved by a number of augmentation techniques. Common thermal-
hydraulic goals are to reduce the size of heat exchanger required for specified heat duty, to upgrade the capacity
of an existing heat exchanger, to reduce the approach temperature difference for the process streams, or to
reduce the pumping power. A preferred approach to the problem of increasing heat exchanger effectiveness,
while maintaining minimum heat exchanger size and operational cost, is to increase the heat transfer exchange
rate.The addition of fins reduces the thermal resistance on that side and thereby increases the net heat transfer
from/to the surface for thesame temperature difference. The heat transfer coefficient can also be higher for
fins.To develop the correlations for forced convection for the inner pipe in tube in tube heat exchanger having
threaded shape using experimental and numerical techniques. This geometry is expected to augment heat
transfer for vortex shedding and turbulence because of internal curvatures and enhanced area available for heat
transfer.In order to do so, the experiments employ tube in tube heat exchanger with two configurations of the
inner tube namely straight smooth tube and threaded tube. The experimentation will be conducted for the
Reynolds number in turbulent region ranging from 6000 to 25,000.
A.E. Bergles, [1] showed that heat energy is conserved by heat transfer enhancement.C.A. Balaras, [2]
reviewed of augmentation techniques for heat transfer surfaces in single-phase heat exchangers.Wolverine INC
[3] An engineering data book was referred to have a insight for enhanced heat exchangers. Kim[4]Studied the
characteristics of flat plate finned-tube heat exchangers with large fin pitch. In this study, 22 heat exchangers
were tested with a variation of fin pitch, number of tube row, and tube alignment. The air-side heat transfer
coefficient decreased with a reduction of the fin pitch and an increase of the number of tube row. The reduction
in the heat transfer coefficient of the four-row heat exchanger coil was approximately 10% as the fin pitch
decreased from 15.0 to 7.5 mm over the Reynolds number range of 500–900 that was calculated based on the
tube diameter. For all fin pitches, the heat transfer coefficient decreased as the number of tube row increased
from 1 to 4. The staggered tube alignment improved heat transfer performance more than 10% compared to the
2. Manufacturing and Comparative Analysis ...
78
inline tube alignment. A heat transfer correlation was developed from the measured data for flat plate finned-
tubes with large fin pitch. The correlation yielded good predictions of the measured data.HT-307[5] was referred
to determine the efficiency of given longitudinal /pin fin and compare it with the theoretical value for the given
fin. Creed Taylor [6] researched on types of heat exchangers used in refrigeration system and its environmental
impact. Friedrich Frass[7] studied principles in heat exchanger designing and constructing heat
exchangers with transverse finned tubes in cross-flow, it is necessary to know correlations for calculating heat
transfer and pressure drop. In addition to the common use of the Reynolds and Nusselt groups of dimensionless
numbers, heat conduction in the fins also has to be accounted for calculating the heat transfer. A reduction
coefficient termed “fin efficiency” is therefore introduced, by which the actual heat transfer coefficient is
multiplied in order to get the apparent heat transfer coefficient. J.A. Livinstone [8] studied heat transfer
enhancement with different types of fins and studied the heat transfer rates. Shiv Kumar Rathor [9] identified
the advantages of low-finned tube Heat Exchangers over Plain tube (Bare Tube) units. To use finned tubes to
advantage in this application, several technical issues were to be addressed. Shell side and tube side pressure,
cost, weight and size of heat exchanger. Hamid Nabati[10] studied on results of heat transfer rates and pressure
drop with different types of fins. The heat exchanger used for this research consists of a rectangular duct fitted
with different shape pin fins, and is heated from the lower plate.
The pin shape and the compact heat exchanger (CHE) configuration were numerically studied to
maximize the heat transfer and minimize the pressure drop across the heat exchanger. A.D.Kadam[11] carried
out simulation of fin and tube type heat exchanger with the help of computer simulation software. Sandeep R.
Desai [12]carried out analysis of fluid elastic vibrations of heat exchanger tubes and its determination of modal
parameters (natural frequency and damping ratios) of the tubes. Kevin Lunsford [13] published a technical paper
on how to improve the heat exchanger performance with simulation programs commercial feasibility etc.K P M
Wipplinger [14] designed a stainless steel finned tube heat exchanger. M V Ghori [15] experimented three-
dimensional CFD simulation and carried out investigation on heat transfer and fluid flow characteristics of two-
row plain Tube and Fin heat exchanger using FLUENT software. Jiin-Yuh Jang [16] this paper suggests a
method for finding the optimal louver angle of a fin heat exchanger by use of simplified conjugate-gradient
method (SCGM) and a three-dimensional computational fluid dynamics model. AlaHasan [17] conducted the
performance of two evaporatively cooled heat exchangers is investigated under similar operating conditions of
air flow rates and inlet hot water temperatures. The heat exchangers are plain and plate-finned circular tube
types which occupy the same volume. Chi-ChuanWang[18] the objective of this paper is to summarize the
recent progress of fin pattern designs. Some of the designs are from the applied patents and some are from the
recent literatures. The fin patterns include interrupted surfaces, enhanced wavy and the vortex generators.
Benefits and the associated constraints of these designs are discussed. S.F Tsai [19]A three-dimensional
numerical study was conducted to assess the heat transfer performance of extended fins in a two-row finned tube
heat exchanger. Fins under investigation were plane and slit types. A finite volume discretization method and a
SIMPLE-based solution algorithm were, respectively, applied to working differential equations and their
discrete counterparts to compute the gas velocities and pressure. W. K. Ding [20] .A circuit data structure
(circuit connection network) for a general description of different circuit configurations in computer programs is
presented. On basis of this data structure, a general tube-by-tube simulation model and the corresponding code
for prediction of plate fin-and-tube heat exchanger performance are developed.
Dimensional Parameters Threaded tube (mm)
(Aluminium)
Straight Tube (mm)
(Aluminium)
Length of the heat exchanger 1000 1000
Inner diameter of the inner tube, di 16 16
Outer diameter of the inner tube, do 26 25
Inner diameter of the outer tube, Di 36 36
Outer diameter of the outer tube, Do 42 42
Pitch distance between threads 2.4 -
Depth of threads 1.5 -
II. METHODOLOGY AND EXPERIMENTATION
Geometry is ascertained based on literature survey, pipe sizes available in market and heat duty.
Manufacturing and fabrication of threaded tube.
Insertion of simple instrumentation for thermal measurement.
Study of variation of Reynolds number on the Nusselt number.
Reduction of data to construct useful heat transfer correlations.
A schematic diagram of the experimental apparatus is shown in Fig 1. The test loops consists of a test section,
hot water loop, cold water loop and data measuring systems.
3. Manufacturing and Comparative Analysis ...
79
Fig1. Schematic Diagram
1. Suction Pipe 2.Heaters 3. Cold Water Pipe 4. Hot Water Sensor 5. Cold Water Sensor
6. Cold Pipe Outlet 7. Threaded Heat Pipe. 8. M.S Outer Pipes 9. Non Threaded Heat Pipe
10. Delivery Pipe 11. FCV 12.Cold Pipe Inlet
The test section is the water-to-water single-phase horizontal double pipe heat exchanger with two
different configurations of the inner tube (threaded and non threaded).
2.1experimental Analysis
A basic strategy to evaluate the heat exchanger’s performance is through the study of parameters like
Nusselt Number, Reynolds number, etc and their impact on the overall heat transfer coefficient of the heat
exchanger. In result table, LMTD, overall heat transfer coefficient, Nusselt numbers across the inner tube are
calculated. The collected data is processed, analyzed and presented Reynolds number (1500 – 31000 range) and
mass flow rates (0.055 to 0.220 kg/s)
III. DESIGN OF DOUBLE PIPE HEAT EXCHANGER BY KERN METHOD
FOR GIVEN SPECIFICATIONS
Hot fluid inlet temperature, Thi= 65°C = 338K
Cold fluid inlet temperature, Tci= 30°C = 303K
Mass flow rate for hot fluid (water), qh = 200LPH
Mass flow rate for cold fluid (water), qc = 200LPH
For the process conditions specified above, design the double pipe heat exchanger of 2000W heat duty.
Thermo-physical properties Hot fluid (water) at
65°C
Cold fluid (water) at
30°C
Density, ρ (kg/m3
) 987.7 997.46
Thermal conductivity, k (W/m-K) 0.658 0.619
Specific heat, Cp (J/Kg-K) 4182 4182
Viscosity, μ (Pa-s) 0.422 x 10-3
0.777 x 10-3
Prandtl number, Pr 2.6062 5.1078
Various heat transfer equations and empirical correlations are used to determine various parameters
such as Reynolds number, Nusselt number, heat transfer coefficient etc. The readings and observations are taken
prior to calculation of above mentioned parameters In present work, experimentation is done for single-phase
water to water tube in tube heat exchanger with threaded and non threaded inner pipe. This analytical work is
further studied in detail and presented.
4. Manufacturing and Comparative Analysis ...
80
results And Discussions
Effect of flow rate on Nusselt Number
Fig 2.Variation of inner tube Nusselt Number with Threaded and Straight inner
tube flow rate for cold 200 LPH
Fig.3.Variation of inner tube Nusselt Number with Threaded and Straight inner
tube flow rate for cold 300 LPH
Fig.4.Variation of inner tube Nusselt Number with Threaded and Straight inner
tube flow rate for cold 400 LPH
5. Manufacturing and Comparative Analysis ...
81
Effect of Nusselt Number on inner tube side Reynolds Number for different configurations of the inner tube
(threaded and Straight)
Fig 5.Variation of inner tube Nusselt Number with Reynolds number for threaded
and Straight tube for cold 200 LPH.
Fig 6. Variation of inner tube Nusselt Number with Reynolds number for
threaded and Straight tube for cold 300 LPH
6. Manufacturing and Comparative Analysis ...
82
Fig 7. Variation of inner tube Nusselt Number with Reynolds number for
threaded and Straight tube for cold 400 LPH
Effect of Convection coefficient for different configurations of the inner tube (threaded and Straight)
Fig.8 Variation of inner tube Convection coefficient with Threaded and
Straight inner tube flow rate for cold 200 LPH
7. Manufacturing and Comparative Analysis ...
83
Fig 9.Variation of inner tube Convection coefficient with Threaded and
Straight innertube flow rate for cold 300 LPH
F
Fig.10.Variation of inner tube Convection coefficient with Threaded and
Straight inner tube flow rate for cold 400 LPH
Qavgfor different configurations of the inner tube (threaded and Straight)
Fig 11.Variation of Qavg with Threaded and Straight inner tube flow rate for
cold 200 LPH
8. Manufacturing and Comparative Analysis ...
84
Fig 12.Variation of Qavg with Threaded and Straight inner tube flow rate for
cold 300 LPH
Fig.13.Variation of Qavg with Threaded and Straight inner tube flow rate for
cold 400 LPH
1. It is observed from the graph that the heat transfer rates of threaded pipe are more as compared to non-
threaded pipe, keeping the cold flow rate (LPH) constant.
2. It is also observed from the graphs, that heat transfer rate for threaded pipe is more than non-threaded pipe for
respective cold mass flow rate.
3. It is clear that the Nusselt Number of inner tube increases with increasing flow rate of water through inner
tube.
IV. CONCLUSIONS
An experimental study has been performed to investigate the performance (pressure drop and Nu
characteristic) for the two configurations of inner tube in the single phase water-to-water tube in tube heat
exchanger (TTHE) i.e. threaded; non threaded. A two to four times more heat transfer enhancement is observed
experimentally for the aforesaid heat exchanger with increased pumping power requirement of twice or thrice.
Thus this work concludes that significant heat transfer enhancement is achieved for the threaded inner tube in
TTHE. The work can be extended further for heavy heat duty industrial applications with wide operating
conditions, different fluids and more precise instrumentation, provided that time and money are not constraints.
9. Manufacturing and Comparative Analysis ...
85
REFERENCES
[1] A.E. Bergles, “The imperative to enhance heat transfer”, Energy Conservation Through Heat Transfer Enhancement of Heat
Exchangers, Turkey, 1998, pp. 547-563.
[2] C.A. Balaras, “A review of augmentation techniques for heat transfer surfaces in single-phase heat exchangers”, Energy Conversion
and Management, Vol. 15, 1990, pp. 899–906
[3] Wolverine INC “ Wolverine Tube heat transfer data book”
[4] Yonghan Kim, Yongchan Kim “Heat transfer characteristics of flat plate finned-tube heat exchangers with large fin pitch”, Vol. 1 26
January 2005
[5] HT 307 “Finned tube heat exchanger” .
[6] Creed Taylor “Measurement of finned-tube heat exchanger performance”.
[7] Friedrich Frass “Principles of finned-tube heat exchanger design for enhanced heat transfer”
[8] J.A.Livingstone“Effective Heat Transfer Enhancement in Finned Tube Heat Exchanger with different Fin Profiles” Vol.2, Issue 2 ,
2013, pp:83-87
[9] Shiv Kumar Rathor “Comparative Analysis of Finned Tube and Bared Tube Type Shell and Tube Heat Exchanger” Vol. 2, Issue 1,
July 2012
[10] Hamid Nabati “Optimal pin fin heat exchanger surface” 2008
[11] A. D.Kadam“ Perfomance simulation of fin and tube heat exchanger” IJESR Vol.2, Issue 10, 2012
[12] Sandeep R Desai “Determination of Modal parameters for finned tube heat exchanger tubes of various configurations” UJME 2013
[13] Kevin Lunsford “ Increasing heat exchanger performance” Bryan research and engineering, inc. 2006
[14] K P M Wipplinger “Stainless steel finned tube heat exchanger design for waste heat recovery”
[15] M. V. Ghori “Numerical Analysis of Tube-fin Heat Exchanger using Fluent”
[16] Jiin-YuhJang”Optimum louver angle design for a louvered fin heat exchanger” IJPS vol.6 pp 6422-6438
[17] AlaHasan “Performance investigation of plain and finned tube evaporatively cooled heat exchangers”
[18] Chi-Chuan Wang “Recent advances in fin-and-tube heat exchanger” Vol.19, 2011, pp.291-301
[19] S. F Tsai “A comparison study on fin surfaces in finned-tube heat exchangers” IJNM Vol.9, 1999 pp.92-106
[20] W.K. Ding, J.F. Fan, Y.L. He, W.Q. Tao, Y.X. Zheng, Y.F. Gao, J. Song “A general simulation model for performance prediction of
plate fin-and-tube heat exchanger with complex circuit configuration” Science Direct, 2011, pp.3106-3116.
[21] R. K. Shah* and D. R Sekulib,University of Kentucky
[22] PiotrWais,“Fin-Tube Heat Exchanger Optimization”PiotrWais,Cracow University of Technology, Department of Thermal Power
Engineering, Poland
[23] Kevin M. Lunsford, “Increasing Heat Exchanger Performance”Bryan Research & Engineering, Inc., Bryan, Texas
[24] Comparative Analysis of Finned Tube and Bared Tube Type Shell and Tube Heat Exchanger Shiv Kumar Rathore, AjeetBergaley
[25] M.R.Jafari Nasr and A. T. Zoghi “Full Analysis Of Low Finned Tube Heat Exchangers”,Research Institute of Petroleum Industry
(RIPI), National Iranian Oil Company (NIOC)