International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
EXPERIMENTAL ANALYSIS OF HEAT TRANSFER AND FLUID FLOW IN MICRO-CHANNEL HEAT SINKijmech
In this paper heat transfer in single phase through micro-channels was studied. The validation of classical correlations of conventional channels to micro-channels is explored. It is found that classical approach is in good agreement with the experimental results of heat transfer in micro-channels .The material used for micro-channel heat sink (MCHS) is copper, experiments were conducted using water as cooling agent in
this study. Micro-channels are made with the help of EDM machine on the upper surface of MCHS. Variation of heat transfer rates, effect of friction factor, effect of pressure drop and variation in temperature distribution is investigated in this study. It is observed in the study that with decrease in
velocity flow friction also decreases.
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.
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.
IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) is an open access international journal that provides rapid publication (within a month) of articles in all areas of mechanical and civil engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in mechanical and civil engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
EXPERIMENTAL ANALYSIS OF HEAT TRANSFER AND FLUID FLOW IN MICRO-CHANNEL HEAT SINKijmech
In this paper heat transfer in single phase through micro-channels was studied. The validation of classical correlations of conventional channels to micro-channels is explored. It is found that classical approach is in good agreement with the experimental results of heat transfer in micro-channels .The material used for micro-channel heat sink (MCHS) is copper, experiments were conducted using water as cooling agent in
this study. Micro-channels are made with the help of EDM machine on the upper surface of MCHS. Variation of heat transfer rates, effect of friction factor, effect of pressure drop and variation in temperature distribution is investigated in this study. It is observed in the study that with decrease in
velocity flow friction also decreases.
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.
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.
IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) is an open access international journal that provides rapid publication (within a month) of articles in all areas of mechanical and civil engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in mechanical and civil engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
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
Experimental Study of Heat Transfer Analysis in Vertical Rod Bundle of Sub Ch...IJMER
The ability of the fluid in taking the heat generated by the nuclear reactor fuel is one
important aspect of reactor safety. These capabilities must be kept high enough to maintain integrity of
the fuel cladding as inside retaining radioactive substances. Study characteristics of forced convection in
the fluid water using seven vertical cylinders heated uniformly in the composition ratio of hexagons with
Pitch/Diameter (P/D) at 1.58 in the hexagon-shaped shell model of the reactor core test equipment in
order to obtain the correlation equation displacement convection force. In this study, the heat flux and
velocity of fluid flow greatly affect the temperature of the fluid. The greater the heat flux given the fluid
temperature is getting higher because of the greater heat flux on the cylinder heating the heat absorbed
by the fluid is also getting bigger. Similarly, the velocity of fluid flow, increasing the velocity of the fluid
flow, the smaller the fluid temperature because by increasing the velocity of fluid flow in the sub channel
the heat received by the fluid on the wane led to the smaller fluid temperature. Heat transfer coefficient
results obtained at a velocity flow of 0.1 m s-1
is 500 Wm-2K
-1
to 23 500 Wm-2K
-1
, at a velocity flow of 0.3
m s
-1
is 3 100 Wm-2K
-1
up to 2 800 Wm-2K
-1
and in velocity flow of 0.5 m s-1
is 3 500 Wm-2K
-1
to 32 500
Wm-2K
-1
. In this experimental study use forced convection flow has a Reynolds number range from 3 991
to 29 537 and Graetz numbers from 1 371 to 41 244. The correlation of forced convection heat transfer as
follows: Nu forced = 1.641 Gz 0.4267
Numerical Analysis of Heat Transfer Enhancement in Pipe-inPipe Helical Coiled...iosrjce
These paper focuses on the effect of the inside tubes at constant value of mass flow rate and variation
of annulus mass flow rate on effect of Dean Number and overall heat transfer coefficient with constant wall
temperature, CFD analysis of a helically coiled heat exchanger. Also deals with the effect of Dean Number with
respect to Reynolds Number and Nusselt Number and Overall Heat Transfer coefficient on change of coil
configuration of helically coiled tube. The particular difference in this study in comparison with the other
similar studies was the boundary conditions for the helical coils. The results indicate that with the decrease the
inner coil diameter, the overall heat transfer coefficient is increased
Experimental Investigation on the Heat Transfer Coefficient of the Thermosyph...IJERA Editor
Two phase closed thermosyphon is a good heat transfer device. A large heat is transferred from evaporator to condenser with relatively a small temperature difference. In the present work, the heat transfer performance of two phase closed thermosyphon is analyzed experimentally with different cross section shape for the thermosyphon tube. A copper thermosyphon has been constructed with three different cross section shape (circular, square and rectangular) having the same hydraulic diameter and length. Methanol is used as the working fluid. The temperature distribution across the thermosyphon outer surface was measured and recorded using thermocouples. The results showed that the heat transfer coefficient increases with the increase of input power, thermal resistance is indirectly proportional to the input power. The maximum heat transfer coefficient (1815 W/m2C) for square cross section at the input power (500 W).
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
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.
HEAT TRANSFER AUGMENTATION IN STEEL QUENCHING BY SPRAY IMPINGEMENT COOLING ME...BIBHUTI BHUSAN SAMANTARAY
The present article discusses the experimental results on heat transfer characteristics of spray impingement cooling of a stationary steel plate. The eexperimental setup consisted of an electrically heated flat stationary steel plate of dimension 120 mm x 120 mm x 4 mm, spray setup, water supply and air supply unit. The effects of various controlling parameters such as air-water pressures, water flow rate, nozzle tip to target distance and impingement density were determined and analysed. The cooling rates were computed from the time dependent temperature history and used to analyse the parametric effects. The results obtained in the study confirmed the higher efficiency of the spray cooling system and the cooling strategy was found advantageous over the conventional cooling methods available in the open literature.
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
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
Experimental Study of Heat Transfer Analysis in Vertical Rod Bundle of Sub Ch...IJMER
The ability of the fluid in taking the heat generated by the nuclear reactor fuel is one
important aspect of reactor safety. These capabilities must be kept high enough to maintain integrity of
the fuel cladding as inside retaining radioactive substances. Study characteristics of forced convection in
the fluid water using seven vertical cylinders heated uniformly in the composition ratio of hexagons with
Pitch/Diameter (P/D) at 1.58 in the hexagon-shaped shell model of the reactor core test equipment in
order to obtain the correlation equation displacement convection force. In this study, the heat flux and
velocity of fluid flow greatly affect the temperature of the fluid. The greater the heat flux given the fluid
temperature is getting higher because of the greater heat flux on the cylinder heating the heat absorbed
by the fluid is also getting bigger. Similarly, the velocity of fluid flow, increasing the velocity of the fluid
flow, the smaller the fluid temperature because by increasing the velocity of fluid flow in the sub channel
the heat received by the fluid on the wane led to the smaller fluid temperature. Heat transfer coefficient
results obtained at a velocity flow of 0.1 m s-1
is 500 Wm-2K
-1
to 23 500 Wm-2K
-1
, at a velocity flow of 0.3
m s
-1
is 3 100 Wm-2K
-1
up to 2 800 Wm-2K
-1
and in velocity flow of 0.5 m s-1
is 3 500 Wm-2K
-1
to 32 500
Wm-2K
-1
. In this experimental study use forced convection flow has a Reynolds number range from 3 991
to 29 537 and Graetz numbers from 1 371 to 41 244. The correlation of forced convection heat transfer as
follows: Nu forced = 1.641 Gz 0.4267
Numerical Analysis of Heat Transfer Enhancement in Pipe-inPipe Helical Coiled...iosrjce
These paper focuses on the effect of the inside tubes at constant value of mass flow rate and variation
of annulus mass flow rate on effect of Dean Number and overall heat transfer coefficient with constant wall
temperature, CFD analysis of a helically coiled heat exchanger. Also deals with the effect of Dean Number with
respect to Reynolds Number and Nusselt Number and Overall Heat Transfer coefficient on change of coil
configuration of helically coiled tube. The particular difference in this study in comparison with the other
similar studies was the boundary conditions for the helical coils. The results indicate that with the decrease the
inner coil diameter, the overall heat transfer coefficient is increased
Experimental Investigation on the Heat Transfer Coefficient of the Thermosyph...IJERA Editor
Two phase closed thermosyphon is a good heat transfer device. A large heat is transferred from evaporator to condenser with relatively a small temperature difference. In the present work, the heat transfer performance of two phase closed thermosyphon is analyzed experimentally with different cross section shape for the thermosyphon tube. A copper thermosyphon has been constructed with three different cross section shape (circular, square and rectangular) having the same hydraulic diameter and length. Methanol is used as the working fluid. The temperature distribution across the thermosyphon outer surface was measured and recorded using thermocouples. The results showed that the heat transfer coefficient increases with the increase of input power, thermal resistance is indirectly proportional to the input power. The maximum heat transfer coefficient (1815 W/m2C) for square cross section at the input power (500 W).
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
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.
HEAT TRANSFER AUGMENTATION IN STEEL QUENCHING BY SPRAY IMPINGEMENT COOLING ME...BIBHUTI BHUSAN SAMANTARAY
The present article discusses the experimental results on heat transfer characteristics of spray impingement cooling of a stationary steel plate. The eexperimental setup consisted of an electrically heated flat stationary steel plate of dimension 120 mm x 120 mm x 4 mm, spray setup, water supply and air supply unit. The effects of various controlling parameters such as air-water pressures, water flow rate, nozzle tip to target distance and impingement density were determined and analysed. The cooling rates were computed from the time dependent temperature history and used to analyse the parametric effects. The results obtained in the study confirmed the higher efficiency of the spray cooling system and the cooling strategy was found advantageous over the conventional cooling methods available in the open literature.
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
After investing in a software platform that would offer the greatest flexibility, it was time to get some content.
“Who has the best chiropractic content?” Steve asked himself.
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
The real estate experts at Kingsbury Homes can help you find affordable homes for sale in Georgetown, Texas. For more information, visit www.kingsburyhomestx.com
Evaluation of Shell and Tube Heat Exchanger Performance by Using ZnO/Water Na...Barhm Mohamad
To examine and investigate the impact of nanofluid on heat exchanger performance, including the total heat transfer, the effect of friction factor, the average Nusselt number, and the thermal efficiency, the output heat transfers of a shell and tube heat exchanger using ZnO nanoparticles suspended in water has been conducted numerically. The governing equations were solved using finite volume techniques and CFD simulations with ANSYS/FLUENT Solver 2021. The nanoparticles volume fractions adopted are 0.2% and 0.35% that used in numerical computations under 200 to 1400 Reynolds numbers range. The increasing of temperature is approximately 13% from the bottom to the top of heat exchanger, while the maximum enhancement of Nusselt number is about 10%, 19% for volume fractions 0.2% and 0.35% respectively. The elevated values of the friction factor at the volumetric ratios of 0.2% and 0.35% are 0.25% and 0.47% respectively. The findings demonstrate that the performance efficiency of shell and tube heat exchanger is enhanced due to the increase in Nusselt number.
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
Performance Analysis of a Shell Tube Condenser for a Model Organic Rankine Cy...IJERA Editor
The global energy demand increases with the economic growth and population rise. Most electrical power is currently generated by conventional methods from fossil fuels. Despite the high energy demand, the conventional energy resources such as fossil fuels have been declining. In addition to this harmful combustion byproducts are resulting global warming. However, the increase of environmental concerns and energy crisis can be minimized by sustainable utilization of the low to medium temperature heat resources. The Organic Rankine Cycle power plant is a very effective option for utilization of low grade heat sources for power generation. Heat exchangers are the main components of the Organic Rankine Cycle power plant which receives heat energy from the heat source to evaporate and condense the low boiling temperature organic working fluid which in turn drives the turbine to generate power. This paper presents a simplified approach to the design, fabrication and performance assessment of a shell tube heat exchanger designed for condenser in a model Organic Rankine Cycle geothermal power plant. The design involved sizing of heat exchanger (condenser) using the LMTD method based on an expected heat transfer rate. The heat exchanger of the model power plant was tested in which hot water simulated geothermal brine. The results of the experiment indicated that the heat exchanger is thermally suitable for the condenser of the model power plant.
Study on Effect of Twisted Tape Insert Geometry in Heat Exchangerijtsrd
The heat exchanger is a device used to transfer heat from hot fluid to cold fluid. The current research reviews existing work conducted in improving performance of heat exchanger by varying geometric profile, baffling space, baffling inclination and use of helical inserts. The existing researches were conducted using both experimental and numerical techniques. The effect of operational parameters on performance of heat exchanger is also presented. Deepak Bhoi | Sudhir Singh Rajput "Study on Effect of Twisted Tape Insert Geometry in Heat Exchanger" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-6 | Issue-2 , February 2022, URL: https://www.ijtsrd.com/papers/ijtsrd49163.pdf Paper URL: https://www.ijtsrd.com/engineering/mechanical-engineering/49163/study-on-effect-of-twisted-tape-insert-geometry-in-heat-exchanger/deepak-bhoi
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
AN EXPERIMENTAL STUDY OF EXERGY IN A CORRUGATED PLATE HEAT EXCHANGERIAEME Publication
In the present work an attempt has been made to investigate the performance of a 3 channel 1-1 pass, corrugated plate heat exchanger. The plates had sinusoidal wavy surfaces with corrugation angle of 450. Hot water at different inlet temperature ranging from 400C to 600C was made to flow in the central channel to get cooled by water in the outer channels.
Numerical Simulation of a Tube in Tube Helical Coiled Heat Exchanger using CFDCarnegie Mellon University
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.
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.
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
EXPERIMENTAL INVESTIGATION OF FLOW CONDENSATION HEAT TRANSFER IN RECTANGULAR ...IAEME Publication
Condensation heat transfer coefficients and pressure drops in horizontal rectangular minichannel was measured using the specially designed aluminium test section with hydraulic diameter of 2mm. The data are reported for steam is a
refrigerant and water as a coolant. The experimental investigation was carried out mass flux range of 88.89 kg/m2
s to 177.78 kg/m2 s, vapour quality ranges from 20-80% and a saturation temperature of 100°C.
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.
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.
Software Delivery At the Speed of AI: Inflectra Invests In AI-Powered QualityInflectra
In this insightful webinar, Inflectra explores how artificial intelligence (AI) is transforming software development and testing. Discover how AI-powered tools are revolutionizing every stage of the software development lifecycle (SDLC), from design and prototyping to testing, deployment, and monitoring.
Learn about:
• The Future of Testing: How AI is shifting testing towards verification, analysis, and higher-level skills, while reducing repetitive tasks.
• Test Automation: How AI-powered test case generation, optimization, and self-healing tests are making testing more efficient and effective.
• Visual Testing: Explore the emerging capabilities of AI in visual testing and how it's set to revolutionize UI verification.
• Inflectra's AI Solutions: See demonstrations of Inflectra's cutting-edge AI tools like the ChatGPT plugin and Azure Open AI platform, designed to streamline your testing process.
Whether you're a developer, tester, or QA professional, this webinar will give you valuable insights into how AI is shaping the future of software delivery.
Builder.ai Founder Sachin Dev Duggal's Strategic Approach to Create an Innova...Ramesh Iyer
In today's fast-changing business world, Companies that adapt and embrace new ideas often need help to keep up with the competition. However, fostering a culture of innovation takes much work. It takes vision, leadership and willingness to take risks in the right proportion. Sachin Dev Duggal, co-founder of Builder.ai, has perfected the art of this balance, creating a company culture where creativity and growth are nurtured at each stage.
Smart TV Buyer Insights Survey 2024 by 91mobiles.pdf91mobiles
91mobiles recently conducted a Smart TV Buyer Insights Survey in which we asked over 3,000 respondents about the TV they own, aspects they look at on a new TV, and their TV buying preferences.
UiPath Test Automation using UiPath Test Suite series, part 3DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 3. In this session, we will cover desktop automation along with UI automation.
Topics covered:
UI automation Introduction,
UI automation Sample
Desktop automation flow
Pradeep Chinnala, Senior Consultant Automation Developer @WonderBotz and UiPath MVP
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
Neuro-symbolic is not enough, we need neuro-*semantic*Frank van Harmelen
Neuro-symbolic (NeSy) AI is on the rise. However, simply machine learning on just any symbolic structure is not sufficient to really harvest the gains of NeSy. These will only be gained when the symbolic structures have an actual semantics. I give an operational definition of semantics as “predictable inference”.
All of this illustrated with link prediction over knowledge graphs, but the argument is general.
Search and Society: Reimagining Information Access for Radical FuturesBhaskar Mitra
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D031201025031
1. International Journal of Computational Engineering Research||Vol, 03||Issue, 12||
An Experimental Investigation on Condensation Heat Transfer of
Microchannel Heat Exchangers
Thanhtrung Dang and Minhhung Doan
Department of Heat and Refrigeration Technology, Ho Chi Minh City University of Technical Education, Ho
Chi Minh City, Vietnam
ABSTRACT:
The present study investigated experimentally condensation heat transfer of two microchannel
heat exchangers. The heat transfer rate of a microchannel heat exchanger was achieved 272.9 W for the
vapor having the inlet temperature of 101 ºC and the mass flow rate of 0.123 g/s and for the cooling
water having the inlet temperature of 32ºC and mass flow rate of 3.1133 g/s. It was also observed that
the heat transfer rate obtained from the counter flow arrangement is always higher than that obtained
from the parallel one: the value obtained from the counter flow arrangement is 1.04 to 1.05 times of that
obtained from the parallel flow. The results for two phases are in good agreement with the results for
single phase. In addition, the condensation heat transfer coefficient in the microchannel heat exchangers
decreases as increasing the inlet cooling water temperature.
KEYWORDS: Microchannel, condensation, configuration, heat exchanger, efficiency.
NOMENCLATURE
h
entalpy
kJ/kg
m
mass flow rate kg/s
Q
heat transfer rate W
T
temperature ºC
Subscripts
i
inlet
o
outlet
v
vapor
w
water
Greek symbols
efficiency
I.
INTRODUCTION
The use of microchannel heat exchangers can bring advantages such as enhanced heat transfer
coefficient and decreased characteristic dimension. The use is found in chemical, medical areas and in micro
electro-mechanical systems (MEMs). In relevant studies of microchannel heat transfer, Hu and Chao [1] studied
five condensation flow patterns for water in silicon micro condenser. For a hydraulic diameter of 73 m and the
range of mass fluxes of steam from 5 to 45 kg/(m2s), the heat transfer coefficients obtained were from 220 to
2400 W/(m2K) and the corresponding pressure drops were from 100 to 750 kPa/m. In the study, the maximum
heat flux achieved was 40 kW/m2. The study indicated that cooling capacity and the coefficient of performance
(COP) of the microchannel condenser were higher than those of the conventional condenser under the same
operating condition. In addition, the amount of fluids used in the heat exchanger systems with microchannel
condensers was smaller than that with the conventional one. Two R410A residential air-conditioning systems,
one with a microchannel condenser and the other with a round-tube condenser, were studied by Park and Hrnjak
[2]. The cooling capacity and the coefficient of performance (COP) of the system with the microchannel
condenser were 3.4% and 13.1% higher, respectively, than those obtained with the round condenser. The
amount of working fluids charged for the system with the microchannel condenser was 9.2% smaller than that
with the round-tube condenser. The numerical model also used to calculate for the non-uniform distribution of
the air and refrigerant. The numerical results did not make a significant difference for predicting the condenser
capacity. Numerical model for microchannel condensers and gas coolers was investigated by Martínez-Ballester
et al. [3].
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2. An Experimental Investigation On Condensation…
The main conclusion of this study is that it is possible to take into account the heat conduction between
tubes in a more fundamental way than other fin efficiency based approaches, which have to apply heat
conduction terms to an approach that uses the adiabatic-fin-tip assumption, which is not satisfied in such cases.
However, this study just indicated in description and validation state only. Cho et al. [4] studied the fabrication
of the micro condenser tube by direct extrusion. The materials used to manufacture for this micro condenser are
A1100 and A3003 aluminum alloy. Because A3003 alloy can be durable when it used in a heat exchanger that
requires high working pressure, so A3003 alloy is more suitable than A1100 alloy for the condenser tube with
eco-friendly refrigerant usage. A comparison of condensation heat transfer and pressure drop of CO 2 in
rectangular microchannels was studied by Heo et al. [5]. The condensation heat transfer coefficients of CO2 in
rectangular microchannels with 7, 23, and 19 ports were experimentally investigated with the variation of the
mass flux. The condensation heat transfer coefficient increased with the decrease in hydraulic diameter, which is
dominant at condensation temperatures of 0 and -5 C. Increasing or decreasing the heat transfer coefficient at
critical vapor quality was observed for the microchannel of 23 ports. The existing models for the prediction of
heat transfer coefficients over-predicted the experimental data and the model of relevant literature showed the
smallest deviation of 47.7%. A study on condensation of compact heat exchanger was done by García-Cascales
et al. [6]. In this study, an iterative algorithm has been suggested for the study of two-row heat exchangers. A
brief state-of-the-art study has been done for condensation in micro- and mini-channels and some remarkable
correlations introduced in the existing literature have been described. They have also been compared under
typical operating conditions. Several heat exchangers working as a condenser or an evaporator have been
studied experimentally and the results obtained have been compared with those provided by the model. Hrnjak
and Litch [7] presented a study of two aluminum condensers: a microchannel condenser (a parallel tube
arrangement between headers and microchannel tubes, having a hydraulic diameter Dh = 0.7 mm) and another
one (with single serpentine macrochannel tube having a hydraulic diameter Dh = 4.06 mm). The ratio between
amount of working fluids charged and capacity of the microchannel condenser was around 76% less than for the
serpentine condenser.
Dang and Teng [8, 9] studied the effects of configurations on performance of the microchannel and
minichannel heat exchangers. Effect of flow arrangement on the heat transfer related behaviors of a
microchannel heat exchanger was presented by Dang and Teng [10]. For all cases done in the study, the heat
flux and performance index obtained from the counter-flow arrangement are always higher than those obtained
from the parallel-flow one: the values obtained from the counter-flow are 1.1 to 1.2 times of those obtained from
the parallel-flow. However, in [8-10] they studied on microchannel heat transfer on single phase. Goss and
Bassoc [11] studied heat transfer during the condensation of R134a inside eight parallel microchannels. The
study indicated that there is no clear influence of the fluid saturation temperature and the heat flux removed on
the heat transfer coefficient for the range tested. On the other hand, the heat transfer coefficient value increases
with rising the mass velocity. It is also demonstrated that the consideration that all of the heat transfer resistance
is due to the heat conduction through the liquid film is a good approximation. The interfacial and disjoining
pressure resistances can be neglected even in the higher quality range. From the above literatures, it is important
to study the efficiency of condensation heat transfer in microchannel heat exchangers. For the present study, two
microchannel heat exchangers with different geometrical configurations will be discussed.
II. METHODOLOGY
The experimental system consists of four major components: the test sections (the microchannel heat
exchangers), pump system, steam boiler, and overall testing loop, as shown in Fig. 1. The vapor produced in the
boiler passes through the micro condenser, where it condenses by the cooling water. Two microchannel heat
exchangers were designed and tested in this study. Figure 2 shows the dimensions of the test sections. The
material for the heat exchangers is aluminum, used as a substrate with thermal conductivity of 237 W/(mK),
density of 2,700 kg/m3, and specific heat at constant pressure of 904 J/(kg K). At each inlet or outlet, a
temperature sensor was set to record temperature values. The inlet and outlet water temperatures were measured
using T-type thermocouples. These thermocouples were inserted into the tubes at the inlets and the outlets. So,
there were total four temperature sensors were used to record data.
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3. An Experimental Investigation On Condensation…
S4
S1
S3
S2
Saturated vapor
P
Inlet cooling water
Outlet cooling water
Outlet cooling water
Condensing vapor
Saturated
vapor
2
7
Intlet cooling water
Condensing vapor
1
6
4
5
4
3
3
Fig. 1. Schematic of the test loop
1. Microchannel heat exchanger;
2. Electric mini Boiler;
3. Mini pump;
4. Water tank;
5. Condensing vapor valve;
6. Adjusting valve;
7. Buffer tank
3
T
L mm
32
mm
A
8.5
mm
mm
9.5
14
mm
W
A
26.5
mm
Wc
Dc
Cross-sectional view A-A
Fig. 2. Dimensions of the test section
||Issn 2250-3005 ||
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4. An Experimental Investigation On Condensation…
Basically, the two microchannel heat exchangers (T1 and T2) have the same dimensions; however, the
substrate thickness of T1 is 1.2 mm while T2 is 1 mm and the channel depth for the cooling water side of T1
channel is 300 m (having hydraulic diameter of 375 µm) while T2 is 180 m (having hydraulic diameter of
265 µm). Geometric parameters of the microchannel heat exchangers are listed in Table 1.
Table 1. Geometric parameters of the microchannel heat exchangers
No.
T1
T2
Dimensions of the channel (m)
Vapor side
Cooling water
side
Wc
Dc
Wc
Dc
500
300
500
300
500
300
500
180
Dimensions of the
substrate (mm)
L
46
46
W
26.5
26.5
T
1.2
1
All channels are connected with a manifold for each inlet or outlet of vapor and cooling water,
respectively. The manifolds have a rectangular shape with the width of 3 mm and the depth of 300 m. Figure 3
shows a photo of the microchannel heat exchanger T1. These test sections of the heat exchangers were
manufactured by precision micromachining [8-10]. Each inlet or outlet of the heat exchangers has crosssectional area of 9 mm2. The four sides of the heat exchanger were thermally insulated by the glass wool with a
thickness of 5 mm. To seal the microchannels, two layers of PMMA (polymethyl methacrylate) are bonded on
the top and bottom sides of the substrate, as indicated in Fig. 3. The physical properties of the PMMA and the
glass wool are listed in Table 2. Accuracies and ranges of testing apparatus are listed in Table 3.
Fig. 3. A photo of the test samples
Table 2. Physical properties of PMMA and glass wool
Material
PMMA
Glass wool
Density
kg/m3
1420
154
Thermal conductivity
W/(mK)
0.19
0.051
Equipments used for the experiments are listed as follows:
[1] Thermocouples, Model PT-100, made by Omega
[2] Mini boiler, Model EMB-S-9, made by ELectromn
[3] Pump, VSP-1200, made by Tokyo Rikakikai
[4] Differential pressure transducer, Model UNIK5000, made by GE Druck
[5] Micro electronic balance, Model TP - 214, made by Denver.
Table 3. Accuracies and ranges of testing apparatuses
Testing apparatus
Thermocouples
Differential pressure transducer
Precision balance
||Issn 2250-3005 ||
Accuracy
0.1 C
0.04% FS
0.0015 g
||December||2013||
Range
0 100 C
0 1 bar
0.0000 210g
Page 28
5. An Experimental Investigation On Condensation…
III. RESULTS AND DISCUSSION
For the experiments carried out in this study, the condensation heat transfer of the heat exchangers is
discussed as follows.
The energy balance equation is calculated by
Qv = Qw
(1)
Or mv(hvi – hvo) = mw(hwo – hwi ) (2)
The heat transfer rate of the heat exchanger, Q, is calculated by
Q = Qw = mw(hwo – hwi )
(3)
where m is mass flow rate (subscripts v and w stand for the vapor side and water side, respectively), hvi, hvo, hwi
and hwo are inlet and outlet enthalpy values of the vapor and cooling water sides, respectively [12].
Experimental data obtained from the microchannel heat exchangers are under the room temperature
condition of 3032C. In order to compare the behaviors of heat transfer between the microchannel heat
exchangers, all experimental conditions for the two heat exchangers were kept the same. The experimental
results for T1 and T2 were recorded by MX 100 recorder; the calculated values were taken by the mean values.
For all cases done in this study, the steam outlet from the mini boiler was the dry saturated vapor having the
absolute pressure of 1.4 bar corresponding with the saturated temperature of 110 ºC. Because of the heat loss
from the outlet of mini boiler to the inlet of microchannel heat exchanger, the inlet temperature of microchannel
heat exchangers for vapor side was kept constantly at 101 ºC.
Table 3. Experimental results were recorded by MX100 recorder
a) for microchannel heat exchanger T1
Channel
CH00001[C]
CH00002[C]
CH00003[C]
CH00004[C]
Start Data No. End Data No.
0
0
0
0
661
661
661
661
Min.
Max.
P-P
Mean
RMS
100.7
71.3
52.3
31.7
101.3
73.0
54.1
32.7
0.6
1.7
0.8
1.0
101.0
72.2
52.7
32.1
101.0
72.2
52.7
32.1
b) for microchannel heat exchanger T2
Channel
CH00001[C]
CH00002[C]
CH00003[C]
CH00004[C]
Start Data No. End Data No.
0
0
0
0
406
406
406
406
Min.
Max.
P-P
Mean
RMS
98.7
38.7
39.7
31.6
102.7
40.0
40.9
32.1
4.0
1.3
1.2
0.5
101.0
39.3
40.2
31.9
101.0
39.3
40.2
31.9
In Table 3, the channel CH00001 is the saturated vapor temperature, the channel CH00002 is the
condensing vapor temperature, the channel CH00003 is the outlet cooling water temperature, and the channel
CH00004 is the inlet cooling water temperature. The results in Table 3 recorded for the cooling water having the
inlet temperature of 32ºC and mass flow rate of 3.1133 g/s and for the vapor having the inlet temperature of 101
ºC. The results shown that the outlet temperatures for both vapor and water obtained from T1 are higher than
those obtained from T2. As a result, the heat transfer rate obtained from the heat exchanger T1 (272.9 W) is
higher than that obtained from the heat exchanger T2 (104.6 W). The heat transfer rate of two heat exchangers
was calculated and shown in Table 4. The Table 4 shows that the mass flow rate of condensing vapor decreases
as reducing the hydraulic diameter of channels.
||Issn 2250-3005 ||
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6. An Experimental Investigation On Condensation…
Table 4. Heat transfer rate for two models
Model
T1
T2
mv
g/s
0.123
0.0481
mw
g/s
3.1133
3.1133
hvi
kJ/kg
2677.64
2677.64
hvo
kJ/kg
306.388
164.64
hwi
kJ/kg
134.14
134.14
hwo
kJ/kg
221.8
167.7
Q
W
272.9
104.6
In this study, effect of flow arrangement on the heat transfer phenomena of the heat exchangers was
also investigated. For the case done in this study, the two models had the same conditions: the temperature of
saturated vapor was 101C and the temperature of cooling water was 32 C with mass flow rate of 3.159 g/s.
Both heat exchangers were tested in the horizontal position. It was observed that the heat transfer rate obtained
from the counter flow arrangement is always higher than that obtained from the parallel one: the value obtained
from the counter flow arrangement is 1.04 to 1.05 times of that obtained from the parallel flow. The results for
two phases are in good agreement with the results for single phase [10]; however, it is shown that the effect of
flow arrangement in two phases is not stronger than single phase, as shown in Table 5.
Table 5. Heat transfer rate with counter flow and parallel flow arrangements
Model
T1
T2
mv
g/s
0.123
0.0481
mw
g/s
3.159
3.159
Heat transfer rate Q, W
Counter flow
Parallel flow
194,63
184,32
111.52
107.197
Figure 4 shows effect of the inlet cooling water temperature to the outlet temperatures of vapor and water
for the microchannel heat exchanger T1. It is observed to see that when the inlet cooling water temperature
increases, the outlet cooling water temperature increases; however, the temperature difference of cooling water
is increasing slowly. As a result, the temperature difference of vapor side decreases or the condensing vapor
temperature increases. It means that the condensation heat transfer efficiency in the microchannel heat
exchangers decreases as increasing the inlet cooling water temperature, as shown in Fig.4.
68
Temperature, oC
58
48
Condensing vapor
Outlet water
38
Water temperature difference
28
18
29.8
30
30.2
30.4
30.6
30.8
Inlet water temperature, oC
Fig. 4. Effect of the inlet cooling water temperature for heat exchanger T1
||Issn 2250-3005 ||
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Page 30
7. An Experimental Investigation On Condensation…
IV. CONCLUSION
Experimental work was done for the two microchannel heat exchangers with rectangular channels
having hydraulic diameters of 375 µm and 265 µm to investigate condensation heat transfer. For the
microchannel heat exchanger T1, the heat transfer rate of 272.9 W was achieved for the vapor having the inlet
temperature of 101 ºC and the mass flow rate of 0.123 g/s and for the cooling water having the inlet temperature
of 32ºC and mass flow rate of 3.1133 g/s. In this study the heat transfer rate obtained from the counter flow
arrangement is always higher than that obtained from the parallel one: the value obtained from the counter flow
arrangement is 1.04 to 1.05 times of that obtained from the parallel flow. The results for two phases are in good
agreement with the results for single phase; however, it is shown that the effect of flow arrangement in two
phases is not stronger than single phase. In addition, the condensation heat transfer efficiency of the
microchannel heat exchanger decreases as increasing the inlet cooling water temperature.
ACKNOWLEDGMENT
The supports of this work by (1) the project (Project No. T2013-22TĐ /KHCN-GV) sponsored by the
specific research fields at Hochiminh City University of Technical Education, Vietnam and (2) the project
(Project No. 65-13/CTHT-NEPTECH) sponsored by New Product & Technology Center (NEPTECH) –
Hochiminh City Department of Science and Technology of Vietnam, are deeply appreciated.
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