Abstract : Co-Axial jets have applications in areas where the mixing of two fluid jets are necessary, the two
fluid jets can be effectively mixed by producing the turbulence flow. Turbulence is a chaotic behavior of the fluid
particles that comes in to picture when the inertia force of the flow dominates the viscous force and it is
characterized by the Reynolds Number. Co-axial jets are effective in producing the turbulence. In the present
study the free compressible turbulent coaxial jet problem will be computed using CFD, and compare with
different non circular coaxial jets based on constant hydraulic diameter and mass flow rate. Turbulence
characteristics of combustion chamber with circular coaxial and non circular coaxial jets are determined and
compared.
Keywords: Coaxial Jet, Turbulence Modeling, Fuel injector, Combustion chamber.
Application of Parabolic Trough Collectorfor Reduction of Pressure Drop in Oi...IJMER
Pipelines are the least expensive and most effective method for the oil transportation.
Due to high viscosity of crude oil, the pressure drop and pumping power requirements are very high.
So it is necessary to bring down the viscosity of crude oil. Heated pipelines are used reduce the oil
viscosity by increasing the oil temperature. Electrical heating and direct flame heating are the common
method used for heating the oil pipeline. In this work, a new application of Parabolic Trough Collector
in the field of oil pipeline transport is introduced for reducing pressure drop in oil pipelines. Oil
pipeline is heated by applying concentrated solar radiation on the pipe surface using a Parabolic
Trough Collector in which the oil pipeline acts as the absorber pipe. 3-D steady state analysis is
carried out on a heated oil pipeline using commercial CFD software package ANSYS Fluent 14.5. In
this work an effort is made to investigate the effect of concentrated solar radiation for reducing
pressure drop in the oil pipeline. The results from the numerical analysis shows that the pressure drop
in oil pipeline is get reduced by heating the pipe line using concentrated solar radiation. From this
work, the application of PTC in oil pipeline transportation is justified.
Numerical Simulation of Flow in a Solid Rocket Motor: Combustion Coupled Pres...inventionjournals
Acomputational study is performed for the simulation of reactive fluid flow in a solid rocket motor chamber with pressure dependent propellant burning surface regression. The model geometry consists of a 2D end burning lab-scale motor. Complete conservation equations of mass, momentum, energy and species are solved with finite rate chemistry. The pressure dependent regressive boundary in the combustion chamber is treated by use of remeshing techniques. Hydrogen and propane combustion processes are examined. Time dependent pressure and burning rate variations are illustrated comprehensively. Temperature and species mass fraction variations are given within the flame zone. Temperature, velocity and density distributions are compared for both constant burning rate and pressure dependent burning rate simulations.
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
Combustion and Mixing Analysis of a Scramjet Combustor Using CFDijsrd.com
The present study is to determine flow field in the three-dimensional scramjet engine combustor with coupled implicit NS equations, the standard k-ε turbulence model are used and the finite-rate/eddy-dissipation reaction model has to be applied to simulate numerically for the flow field of the hydrogen, diesel and methane fueled scramjet combustor with a planer strut flame holder under two different working conditions, the working condition include the cold flow and engine ignition. ANSYS Fluent software is used to solve the analysis, with hot and cold inlet velocities, the mach number for air and fluids are 2 and 1 respectively, inflow fluids are varied as hydrogen, diesel and methane. Due to combustion the recirculation region behind the wedge becomes larger as compared to mixing case and it acts as a flame holder for the methane (CH4), hydrogen (H2) and diesel (C10H22) diffusion. It is also evident from the simulation studies; the combustion affects the flow field significantly. The leading edge shock reflected off the upper and lower combustor walls facilitates on setting of combustion when it hits the wake in a region where large portions of the injected fuel have been mixed up with the air. The pressure, velocity and temperature distributions along the geometry are estimated and discussed.
Application of Parabolic Trough Collectorfor Reduction of Pressure Drop in Oi...IJMER
Pipelines are the least expensive and most effective method for the oil transportation.
Due to high viscosity of crude oil, the pressure drop and pumping power requirements are very high.
So it is necessary to bring down the viscosity of crude oil. Heated pipelines are used reduce the oil
viscosity by increasing the oil temperature. Electrical heating and direct flame heating are the common
method used for heating the oil pipeline. In this work, a new application of Parabolic Trough Collector
in the field of oil pipeline transport is introduced for reducing pressure drop in oil pipelines. Oil
pipeline is heated by applying concentrated solar radiation on the pipe surface using a Parabolic
Trough Collector in which the oil pipeline acts as the absorber pipe. 3-D steady state analysis is
carried out on a heated oil pipeline using commercial CFD software package ANSYS Fluent 14.5. In
this work an effort is made to investigate the effect of concentrated solar radiation for reducing
pressure drop in the oil pipeline. The results from the numerical analysis shows that the pressure drop
in oil pipeline is get reduced by heating the pipe line using concentrated solar radiation. From this
work, the application of PTC in oil pipeline transportation is justified.
Numerical Simulation of Flow in a Solid Rocket Motor: Combustion Coupled Pres...inventionjournals
Acomputational study is performed for the simulation of reactive fluid flow in a solid rocket motor chamber with pressure dependent propellant burning surface regression. The model geometry consists of a 2D end burning lab-scale motor. Complete conservation equations of mass, momentum, energy and species are solved with finite rate chemistry. The pressure dependent regressive boundary in the combustion chamber is treated by use of remeshing techniques. Hydrogen and propane combustion processes are examined. Time dependent pressure and burning rate variations are illustrated comprehensively. Temperature and species mass fraction variations are given within the flame zone. Temperature, velocity and density distributions are compared for both constant burning rate and pressure dependent burning rate simulations.
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
Combustion and Mixing Analysis of a Scramjet Combustor Using CFDijsrd.com
The present study is to determine flow field in the three-dimensional scramjet engine combustor with coupled implicit NS equations, the standard k-ε turbulence model are used and the finite-rate/eddy-dissipation reaction model has to be applied to simulate numerically for the flow field of the hydrogen, diesel and methane fueled scramjet combustor with a planer strut flame holder under two different working conditions, the working condition include the cold flow and engine ignition. ANSYS Fluent software is used to solve the analysis, with hot and cold inlet velocities, the mach number for air and fluids are 2 and 1 respectively, inflow fluids are varied as hydrogen, diesel and methane. Due to combustion the recirculation region behind the wedge becomes larger as compared to mixing case and it acts as a flame holder for the methane (CH4), hydrogen (H2) and diesel (C10H22) diffusion. It is also evident from the simulation studies; the combustion affects the flow field significantly. The leading edge shock reflected off the upper and lower combustor walls facilitates on setting of combustion when it hits the wake in a region where large portions of the injected fuel have been mixed up with the air. The pressure, velocity and temperature distributions along the geometry are estimated and discussed.
5 ijreh feb-2018-1-aerodynamically study by mathematicalAI Publications
The flow field and mixing characters of high efficiency vortices in one type of Radially Stratified Flame Core Burner RSFC where analysed through Cold computing fluid dynamics model CFD in accordance with Mathematical model for flame visualization. The model gives good results and clears the important aerodynamics features of a typical low Nitrogen Oxides NOx of internal staging schematic. The model can be used to evaluate this design performance or to get the necessary information for development its efficiency in accordance with the global demand to clean energy with high efficiency and low NOx emissions. The mixing of this burner dominated by coherent structures, so it is outperform the molecular diffusivity and the length which fluids will mix is independent of the fluid velocity and can determined only from Taylor macroscale which related by the physical size of the fluid domain or in better understanding with the internal recirculating zone dimensions because it is form a region for axial mixing for species and smear out their residence time distribution.
Basic Unit Conversions for Turbomachinery Calculations Vijay Sarathy
Turbomachinery equipment like centrifugal pumps & compressors have their performance stated as a function of Actual volumetric flow rate [Q] & Head [m/bar]. The following tutorial describes how pump/compressor head can be expressed in energy terms as ‘kJ/kg’. Turbomachinery head expressed in kJ/kg describes, how many kJ of energy is required to compress 1 kg of gas for a given pressure ratio. The advantage of using energy terms to estimate absorbed power is that it is based on the amount of ‘mass’ compressed which is independent of pressure and temperature of a fluid.
MODELLING FOR CROSS IGNITION TIME OF A TURBULENT COLD MIXTURE IN A MULTI BURN...ijcsa
The impact of Cross Ignition process (CI) in the gas turbine operation and environmental issue is still
investigated for extending the efficiency of gas turbine engines and meanwhile decreasing the environment
pollution.This paper presents various constructive influential parameters and analysis of their related
interaction during CI. A developed computational model for determination of cross-ignition time (CIT) is
proposed, based on previous relevant models for thermal analysis and for distinguishing of heat fluxes in
combustion processes.
Due to the first analysis of theoretical results, experimental investigation for various operating conditions
were essential to validate the developed computational model of the CIT. Thus, a simple experimental test
rig is designed for this purpose, and for validation of certain conditions of the computational model.
Meanwhile, for expanding the investigations in higher energy conversion and reducing expensive testprocedures,
that are conducted during critical test running, a new strategy is proposed for simulating the
thermal heat fluxes throughout the burners compartment model by implementation of Computational Fluid
Dynamic (CFD).
Finally, new constructive criteria based on the validated investigations will enable the future generation of
gas turbine combustors to operate in critical conditions.
A general interest to reduce fossil fuel consumption and to limit combustion
emissions, increase the efficiency of combustion chambers. One of the most important
processes in a gas turbine combustor, influencing to a large extent the efficiency of the
entire combustion process is the mixing between a swirling annular jet (primary air) and
the non-swirling inner jet (fuel).In normal swirling combustor, primary swirling air is
only supplied to the chamber and is mixed with the fuel but we here introduce a small
duct in the chamber containing a small amount of air without swirl and make it to mix
with the fuel and the primary swirling air. We have modified the design of the swirl
combustor by introducing a bluff body over the flow of the turbulent jet through which the
turbulent air will pass causing the axial velocity. For the purpose of simulation of the
required model of swirl combustor we are using the recent tools like ANSYS, ICEM, CFD
and FLUENT software’s. Using these tools the numerical investigation has been done.
The various values that are obtained are compared with the previous results of the swirl
combustor and the increase in the efficiency of the combustion has been noted
Improving the Heat Transfer Rate for Multi Cylinder Engine Piston and Piston ...IOSR Journals
The four stroke otto engine uses just one of the four strokes to perform work. This causes various
problems: The engine runs jerkily, and this can only be prevented by a large flywheel, which needs a lot of
space and weights pretty much in addition. In this thesis, thermal loads and pressures produced in the multi
cylinder petrol engine Toyota 86 Car by varying compression ratios 14:1, 15:1, 18:1, 20:1 and 25:1 are
calculated by mathematical correlations And also calculating the effect of these thermal loads on piston and
piston rings by varying materials Cast Iron, Aluminum Alloy 6061 for piston and Cast Iron and Steel for piston
rings.FEA transient thermal analysis is performed on the parametric model to validate the effect of thermal
loads on piston and piston rings for different materials. The optimum value of compression ratio and the better
material is determined by analysis results to improve the heat transfer rate of multi cylinder engine piston and
piston rings. Dynamic analysis is done on the piston by applying the pressures developed and also static
analysis by applying the maximum pressure.
Fundamental Aspects of Droplet Combustion ModellingIJERA Editor
The present paper deals with important aspects of liquid droplet evaporation and combustion. A detailed
spherically symmetric, single component droplet combustion model is evolved first by solving time dependent
energy and species conservation equations in the gas phase using finite difference technique. Results indicate
that the flame diameter
F
first increases and then decreases and the square of droplet diameter decreases
linearly with time. Also, the
FD/
ratio increases throughout the droplet burning period unlike the quasi-steady
model where it assumes a large constant value. The spherically symmetric model is then extended to include the
effects of forced convection. Plots of
2 D
and droplet mass burning rate
mf
versus time are obtained for steady
state, droplet heating and heating with convection cases for a n-octane droplet of 1.3 mm diameter burning in
standard atmosphere. It is observed that the mass burning rate is highest for forced convective case and lowest
for droplet heating case. The corresponding values of droplet lifetime follow the inverse relationship with the
mass burning rate as expected. Emission data for a spherically symmetric, 100
m
n-heptane droplet burning
in air are determined using the present gas phase model in conjunction with the Olikara and Borman code [1]
with the aim of providing a qualitative trend rather than quantitative with a simplified approach. It is observed
that the products of combustion maximise in the reaction zone and NO concentration is very sensitive to the
flame temperature. This paper also discusses the general methodology and basic governing equations for
analysing multicomponent and high pressure droplet vaporisation/combustion in a comprehensible manner. The
results of the present study compare fairly well with the experimental/theoretical observations of other authors
for the same conditions. The droplet sub models developed in the present work are accurate and yet simple for
their incorporation in spray combustion codes.
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.
This paper gives a short overview of the theoretical and practical aspects of a thermal diffusion column, of the most important applications of 13C and describes a thermal diffusion cascade for enrichment of this isotope.
Solar air heater (SAH), which is the most essential component of solar drying systems, receive solar energy and convert it into thermal energy. This review presents descriptions and previous works conducted on performances analysis of SAHs. Exergoenviroeconomic, exergoenvironmental, environmental, and exergy analyses are also presented. In addition, results on the performances of SAHs are summarized. The exergy and energy efficiencies of SAHs at laboratorium testing range from 8% to 61% and from 30% to 79%, respectively.
Mathematical Modelling: A Comparatively Mathematical Study Model Base between...IOSR Journals
In this paper, we have studied on the topic of „Corruption‟. Also, I will try to find or study the effect of corruption on the Development of the country or any country of the world. Therefore, how find the solution of the problem of corruption will be destroyed completely from the society. We have observed that the Development of the country depends upon Corruption. That is, when the Corruption increases, Development decreases automatically of any country of the world. Therefore, I will try to find the formula on the problem of „Relation between the Corruption and Development of any field or any country of the world‟. Also, I have to highlight the concept of „Application of Mathematical modeling in the interesting problem “corruption” in every field of our country or world .Also, Applied Mathematics focuses on the formulation and study of Mathematical Models .Thus the activity of Applied Mathematics is vitally connected with Research in Pure Mathematics. So I will try to study on it and find, what is corruption and quantity of corruption and also find the growth of corruption and how it will decay? Now we convert this areal world problem to mathematics problem and find some formulae on it such as Mathematical Corruption Growth formula, Mathematical Constant corruption level formula and Mathematical decay of corruption formula.
5 ijreh feb-2018-1-aerodynamically study by mathematicalAI Publications
The flow field and mixing characters of high efficiency vortices in one type of Radially Stratified Flame Core Burner RSFC where analysed through Cold computing fluid dynamics model CFD in accordance with Mathematical model for flame visualization. The model gives good results and clears the important aerodynamics features of a typical low Nitrogen Oxides NOx of internal staging schematic. The model can be used to evaluate this design performance or to get the necessary information for development its efficiency in accordance with the global demand to clean energy with high efficiency and low NOx emissions. The mixing of this burner dominated by coherent structures, so it is outperform the molecular diffusivity and the length which fluids will mix is independent of the fluid velocity and can determined only from Taylor macroscale which related by the physical size of the fluid domain or in better understanding with the internal recirculating zone dimensions because it is form a region for axial mixing for species and smear out their residence time distribution.
Basic Unit Conversions for Turbomachinery Calculations Vijay Sarathy
Turbomachinery equipment like centrifugal pumps & compressors have their performance stated as a function of Actual volumetric flow rate [Q] & Head [m/bar]. The following tutorial describes how pump/compressor head can be expressed in energy terms as ‘kJ/kg’. Turbomachinery head expressed in kJ/kg describes, how many kJ of energy is required to compress 1 kg of gas for a given pressure ratio. The advantage of using energy terms to estimate absorbed power is that it is based on the amount of ‘mass’ compressed which is independent of pressure and temperature of a fluid.
MODELLING FOR CROSS IGNITION TIME OF A TURBULENT COLD MIXTURE IN A MULTI BURN...ijcsa
The impact of Cross Ignition process (CI) in the gas turbine operation and environmental issue is still
investigated for extending the efficiency of gas turbine engines and meanwhile decreasing the environment
pollution.This paper presents various constructive influential parameters and analysis of their related
interaction during CI. A developed computational model for determination of cross-ignition time (CIT) is
proposed, based on previous relevant models for thermal analysis and for distinguishing of heat fluxes in
combustion processes.
Due to the first analysis of theoretical results, experimental investigation for various operating conditions
were essential to validate the developed computational model of the CIT. Thus, a simple experimental test
rig is designed for this purpose, and for validation of certain conditions of the computational model.
Meanwhile, for expanding the investigations in higher energy conversion and reducing expensive testprocedures,
that are conducted during critical test running, a new strategy is proposed for simulating the
thermal heat fluxes throughout the burners compartment model by implementation of Computational Fluid
Dynamic (CFD).
Finally, new constructive criteria based on the validated investigations will enable the future generation of
gas turbine combustors to operate in critical conditions.
A general interest to reduce fossil fuel consumption and to limit combustion
emissions, increase the efficiency of combustion chambers. One of the most important
processes in a gas turbine combustor, influencing to a large extent the efficiency of the
entire combustion process is the mixing between a swirling annular jet (primary air) and
the non-swirling inner jet (fuel).In normal swirling combustor, primary swirling air is
only supplied to the chamber and is mixed with the fuel but we here introduce a small
duct in the chamber containing a small amount of air without swirl and make it to mix
with the fuel and the primary swirling air. We have modified the design of the swirl
combustor by introducing a bluff body over the flow of the turbulent jet through which the
turbulent air will pass causing the axial velocity. For the purpose of simulation of the
required model of swirl combustor we are using the recent tools like ANSYS, ICEM, CFD
and FLUENT software’s. Using these tools the numerical investigation has been done.
The various values that are obtained are compared with the previous results of the swirl
combustor and the increase in the efficiency of the combustion has been noted
Improving the Heat Transfer Rate for Multi Cylinder Engine Piston and Piston ...IOSR Journals
The four stroke otto engine uses just one of the four strokes to perform work. This causes various
problems: The engine runs jerkily, and this can only be prevented by a large flywheel, which needs a lot of
space and weights pretty much in addition. In this thesis, thermal loads and pressures produced in the multi
cylinder petrol engine Toyota 86 Car by varying compression ratios 14:1, 15:1, 18:1, 20:1 and 25:1 are
calculated by mathematical correlations And also calculating the effect of these thermal loads on piston and
piston rings by varying materials Cast Iron, Aluminum Alloy 6061 for piston and Cast Iron and Steel for piston
rings.FEA transient thermal analysis is performed on the parametric model to validate the effect of thermal
loads on piston and piston rings for different materials. The optimum value of compression ratio and the better
material is determined by analysis results to improve the heat transfer rate of multi cylinder engine piston and
piston rings. Dynamic analysis is done on the piston by applying the pressures developed and also static
analysis by applying the maximum pressure.
Fundamental Aspects of Droplet Combustion ModellingIJERA Editor
The present paper deals with important aspects of liquid droplet evaporation and combustion. A detailed
spherically symmetric, single component droplet combustion model is evolved first by solving time dependent
energy and species conservation equations in the gas phase using finite difference technique. Results indicate
that the flame diameter
F
first increases and then decreases and the square of droplet diameter decreases
linearly with time. Also, the
FD/
ratio increases throughout the droplet burning period unlike the quasi-steady
model where it assumes a large constant value. The spherically symmetric model is then extended to include the
effects of forced convection. Plots of
2 D
and droplet mass burning rate
mf
versus time are obtained for steady
state, droplet heating and heating with convection cases for a n-octane droplet of 1.3 mm diameter burning in
standard atmosphere. It is observed that the mass burning rate is highest for forced convective case and lowest
for droplet heating case. The corresponding values of droplet lifetime follow the inverse relationship with the
mass burning rate as expected. Emission data for a spherically symmetric, 100
m
n-heptane droplet burning
in air are determined using the present gas phase model in conjunction with the Olikara and Borman code [1]
with the aim of providing a qualitative trend rather than quantitative with a simplified approach. It is observed
that the products of combustion maximise in the reaction zone and NO concentration is very sensitive to the
flame temperature. This paper also discusses the general methodology and basic governing equations for
analysing multicomponent and high pressure droplet vaporisation/combustion in a comprehensible manner. The
results of the present study compare fairly well with the experimental/theoretical observations of other authors
for the same conditions. The droplet sub models developed in the present work are accurate and yet simple for
their incorporation in spray combustion codes.
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.
This paper gives a short overview of the theoretical and practical aspects of a thermal diffusion column, of the most important applications of 13C and describes a thermal diffusion cascade for enrichment of this isotope.
Solar air heater (SAH), which is the most essential component of solar drying systems, receive solar energy and convert it into thermal energy. This review presents descriptions and previous works conducted on performances analysis of SAHs. Exergoenviroeconomic, exergoenvironmental, environmental, and exergy analyses are also presented. In addition, results on the performances of SAHs are summarized. The exergy and energy efficiencies of SAHs at laboratorium testing range from 8% to 61% and from 30% to 79%, respectively.
Mathematical Modelling: A Comparatively Mathematical Study Model Base between...IOSR Journals
In this paper, we have studied on the topic of „Corruption‟. Also, I will try to find or study the effect of corruption on the Development of the country or any country of the world. Therefore, how find the solution of the problem of corruption will be destroyed completely from the society. We have observed that the Development of the country depends upon Corruption. That is, when the Corruption increases, Development decreases automatically of any country of the world. Therefore, I will try to find the formula on the problem of „Relation between the Corruption and Development of any field or any country of the world‟. Also, I have to highlight the concept of „Application of Mathematical modeling in the interesting problem “corruption” in every field of our country or world .Also, Applied Mathematics focuses on the formulation and study of Mathematical Models .Thus the activity of Applied Mathematics is vitally connected with Research in Pure Mathematics. So I will try to study on it and find, what is corruption and quantity of corruption and also find the growth of corruption and how it will decay? Now we convert this areal world problem to mathematics problem and find some formulae on it such as Mathematical Corruption Growth formula, Mathematical Constant corruption level formula and Mathematical decay of corruption formula.
An Overview of Intrusion Detection and Prevention Systems (IDPS) and Security...IOSR Journals
Technical solutions, introduced by policies and implantations are essential requirements of an
information security program. Advanced technologies such as intrusion detection and prevention system (IDPS)
and analysis tools have become prominent in the network environment while they involve with organizations to
enhance the security of their information assets. Scanning and analyzing tools to pinpoint vulnerabilities, holes
in security components, unsecured aspects of the network and deploying of IDPS technology are highlighted.
Fluorescence technique involves the optical detection and spectral analysis of light emitted by a substance undergoing a transition from an excited electronic state to a lower electronic state. The aim of this study is to assess the -amino levulinic acid (-ALA) uptake. Based on image processing technique, Matlab was used to analyze the fluorescence images resulted from activation of (-ALA) and follow its uptake along one week. Analyzing the RGB colours pixel profile from obtained results showed different profiles for malignant tissues, normal tissues, treated just after PDT and finally at one week post PDT. The treated tissues fluorescence profile showed changes from closer to malignant tissue profile till been closed to normal one.
“Prevalent Clinical Entities Of Hilly Regions, Aetio-Pathogenesis Factors, An...IOSR Journals
Certain Surgical Clinical Conditions Manifests To Variable Extents With High
Prevalence In Hilly Regions. The Discrete Analysis Of Different Aetio-Pathogenesis Factors & Resultant Patho-
Physiological Changes Exhibit Comparative Co-Relation To Clinical Manifestations, ManageMent GuideLines &
OverAll Result OutCome ParaMetres.
Non- Newtonian behavior of blood in very narrow vesselsIOSR Journals
The purpose of the study is to get some qualitative and quantitative insight into the problem of flow in vessels under consideration where the concentration of lubrication film of plasma is present between each red cells and tube wall. This film is potentially important in region to mass transfer and to hydraulic resistance, as well as to the relative resistance times of red cells and plasma in the vessels network.
Perishable Inventory Model Having Weibull Lifetime and Time Dependent DemandIOSR Journals
In this paper we develop and analyse an inventory model for deteriorating items with Weibull rate of decay and time dependent demand. Using the differential equations, the instantaneous state of inventory at time‘t’, the amount of deterioration etc. are derived. With suitable cost considerations the total cost function and profit rate function are also obtained by maximizing the profit rate function, the optimal ordering and pricing policies of the model are derived. The sensitivity of the model with respect to the parameters is discussed through numerical illustration. It is observed that the deteriorating parameters have a tremendous influence on the optimal selling price and ordering quantity.
Analysis of turbocharger performance for jet assisted vertical takeoff and la...Ijrdt Journal
This paper gives a brief analysis on the performance parameters of a Turbocharger, by fabricating a separate combustion chamber and mocking the working of a jet engine. Parameters such as variation of specific heat, dimensionless flow parameters, variation of turbulence, conductivity, thrust developed etc are studied using simulation of the model, and compared with the actual working of the prototype. It can be conveniently proposed from the experiment that turbocharger can be used effectively for developing vertical take-off assist.
A Critical Review on the Concept of Effect on Scavenging and Fuel Injection T...ijsrd.com
In present study, A spark ignition and a compression ignition engine with uniflow valve scavenging of the cylinder and a transfer valve in the piston crown have been described. A great disadvantage of two-stroke engines is ports which are made in the cylinder bearing surface. Under the heat which is realised during the combustion, the thermal extension of the range in proximity of the ports and other parts of the cylinder is different and so the distortion of the geometry of the cylinder liner surface force the designer to make the clearance between the piston and the cylinder liner bigger. This paper presents the critical review to study the effect of fuel injection timing and scavenging using diesel on the combustion and emission characteristics of a single cylinder, two stroke, air cooled direct injection diesel engine. It is well known that injection strategies including the injection timing and pressure play the most important role in determining engine performance, especially in scavenging emissions. However, the injection timing and pressure quantitatively affect the performance of the diesel engine.
The mean key variable to control the burner performance for safe and efficient operations is the amount of excess air or oxygen which flow to react with fuel. In accordance with Typical Draft Profile in a Natural Draft furnace the numerical results of computing fluid dynamics model of the air flow from the environment to the burner by adjusting the area of air box prototype openings will give the necessary information to adjust the performance of burner as optimum. The model of air box prototype is useful tool in applying similarity theory on another burners̕ designs which depends the air box tools to calibrate the quantity of combustion air flow to the burner.
The present paper describes some results of research in the area of twin spark ignition engine. The potential of dual plug spark ignition engine is assessed by studying its performance and emission characteristics relative to that of single plug ignition engine using gasoline as fuel at different ignition timings. A new dual ignition engine has been developed by introducing two spark plugs at suitable locations. Experiments were conducted at different load conditions and three different ignition timings. The results have shown that performance of dual plug engine is comparatively better than the conventional single plug ignition engine under all three ignition timings. The results have shown considerable performance improvement in power output and thermal efficiency, as well as reduction in BSFC, HC, and CO emission in dual plug mode of operation.
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
1 ijebm jan-2018-1-combustion adjustment in a naturalAI Publications
Shortage of detailed and accurate experimental data on fuel-air mixing in furnaces is due to the difficulty and complexity of measurements in flames. Although it may be possible with infra-Red camera to obtain an indication of what happens in the furnace by graphical image resolution this is not expected to be sufficiently detailed because it contains only the temperature gradient. More detailed information, however, may be obtained from the simulated resolution using Computational Fluid Dynamics (CFD) technique where the total number of elements/points defines the detailed level that can be displayed or captured in graphical image. Simulation resolution studies two aspects of the momentum effects on flame which are the forward momentum normally associated with the average outlet velocity of the combustion products and the lateral momentum caused by swirl. Following the American Petroleum Institute guidelines (API 560) for combustion adjustment in furnaces, it may be possible to have less emission and a maximum efficiency, but the potential interaction between the several operation and design factors are not thereby considered as in a mathematical model of CFD.
Review of Gas Turbine Combustion Chamber Designs to Reduce EmissionsIJAEMSJORNAL
Ensuring the environmental safety of aircraft engines is an important task for developers. This problem is becoming more urgent due to an increase in engine power, since an increase in power is achieved primarily by increasing the temperature in the combustion chamber, leading to an increase in NOx emissions. In this study, the problem of emission in the aviation industry and ways to solve it were considered. Separately, the method of reducing emissions by changing the design of combustion chambers was considered in more detail.
Simulation of gas turbine blade for enhancement of efficiency of gas turbine...IJMER
As day by day population of the world is increasing and our resources are frequently reducing
hence to meet this demand of the world of energy we have to move to a device which have a maximum
efficiency for the condition turbo-machinery are better suited machines having a good efficiency, in
which a Gas turbine is best example of turbo- machinery Turbine is the part of gas turbine which provide
the power to compressor to run or provide power to external source from where energy can be extracted
by attaching alternator in the shaft of Gas turbine. As in earlier a lot of work have been done by the
researcher to increase the efficiency and standard of Gas turbine by the method of film cooling, coating,
and curvature of blade to protect the blade from high temperature of 1200 C° inside the Gas turbine to
increase the life of blade without considering about the efficiency of the engine As in this work is to
enhancement of efficiency of Gas turbine. Gas turbine blade is very important component of engine as
they are attached to both turbine or compressor and turbine provide energy to compressor hence the
turbine blade are more important component to enhance the efficiency which will be analyzed on the
basis of blade height area of fluid flow , area of blade thickness and angles . This simulation is based on
the define value of temperature pressure density of fluid and solid used in blade construction will be
meshed in ANSYS and calculation on the basis of FEM and the result from this calculation over the
temperature and fluid flow inside the gas turbine of different number of blade is studied will be compare
to reach high efficiency point. By determent these value output is formulated on graph chart and will be
studied and result obtain
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.
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.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
COLLEGE BUS MANAGEMENT SYSTEM PROJECT REPORT.pdfKamal Acharya
The College Bus Management system is completely developed by Visual Basic .NET Version. The application is connect with most secured database language MS SQL Server. The application is develop by using best combination of front-end and back-end languages. The application is totally design like flat user interface. This flat user interface is more attractive user interface in 2017. The application is gives more important to the system functionality. The application is to manage the student’s details, driver’s details, bus details, bus route details, bus fees details and more. The application has only one unit for admin. The admin can manage the entire application. The admin can login into the application by using username and password of the admin. The application is develop for big and small colleges. It is more user friendly for non-computer person. Even they can easily learn how to manage the application within hours. The application is more secure by the admin. The system will give an effective output for the VB.Net and SQL Server given as input to the system. The compiled java program given as input to the system, after scanning the program will generate different reports. The application generates the report for users. The admin can view and download the report of the data. The application deliver the excel format reports. Because, excel formatted reports is very easy to understand the income and expense of the college bus. This application is mainly develop for windows operating system users. In 2017, 73% of people enterprises are using windows operating system. So the application will easily install for all the windows operating system users. The application-developed size is very low. The application consumes very low space in disk. Therefore, the user can allocate very minimum local disk space for this application.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
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Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
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.
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.
Courier management system project report.pdfKamal Acharya
It is now-a-days very important for the people to send or receive articles like imported furniture, electronic items, gifts, business goods and the like. People depend vastly on different transport systems which mostly use the manual way of receiving and delivering the articles. There is no way to track the articles till they are received and there is no way to let the customer know what happened in transit, once he booked some articles. In such a situation, we need a system which completely computerizes the cargo activities including time to time tracking of the articles sent. This need is fulfilled by Courier Management System software which is online software for the cargo management people that enables them to receive the goods from a source and send them to a required destination and track their status from time to time.
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The CFD Analysis of Turbulence Characteristics in Combustion Chamber with Non Circular Co-Axial Jets
1. IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE)
e-ISSN: 2278-1684,p-ISSN: 2320-334X, Volume 6, Issue 2 (Mar. - Apr. 2013), PP 01-10
www.iosrjournals.org
www.iosrjournals.org 1 | Page
The CFD Analysis of Turbulence Characteristics in Combustion
Chamber with Non Circular Co-Axial Jets
N L Narasimha Reddy1
, P Manivannan2
and K M Kiran Babu3
1
(Aeronautical Engineering, Hindustan University, Chennai, India)
2
(Aeronautical Engineering, Hindustan University, Chennai, India)
3
(Aeronautical Engineering, Hindustan University, Chennai, India)
Abstract : Co-Axial jets have applications in areas where the mixing of two fluid jets are necessary, the two
fluid jets can be effectively mixed by producing the turbulence flow. Turbulence is a chaotic behavior of the fluid
particles that comes in to picture when the inertia force of the flow dominates the viscous force and it is
characterized by the Reynolds Number. Co-axial jets are effective in producing the turbulence. In the present
study the free compressible turbulent coaxial jet problem will be computed using CFD, and compare with
different non circular coaxial jets based on constant hydraulic diameter and mass flow rate. Turbulence
characteristics of combustion chamber with circular coaxial and non circular coaxial jets are determined and
compared.
Keywords: Coaxial Jet, Turbulence Modeling, Fuel injector, Combustion chamber.
I. INTRODUCTION
Extensive research into noncircular jets has been performed in the past two decades or so, largely due
to their potential to entrain ambient fluid more effectively than comparable circular jets. The superior mixing
capability of such jets is experimentally related either to the non-uniform curvature or their initial parameter,
relative to the evenness for the circular configuration, or to the instabilities produced by the initial perimeter’s
sharp corners through the asymmetric distribution of pressure and mean flow field[17]
. Both phenomena are
deduced to accelerate three- dimensionality of the jet structures, therefore causing greater entraining and mixing.
For elliptic and rectangular jets, azimuthal curvature variation of initial vortical structure produces non-uniform
self-induction and three-dimensional structures. As a result, these flows spread more rapidly in the minor axis
plane than in the major axis plane, causing ― axis switching‖ at a certain distance from the nozzle exit.[17]
, For
corner containing configurations, the corners promote the formation of fine scale mixing [6,8]
. The above
experimental results have also been demonstrated in a number of numerical simulations. [13, 14, 15]
. The review of
Gutmark and Grinstein [17]
summarizes both experimental and numerical studies in the context of non-circular
jets. Note however that previous investigations on noncircular jets, [2-3, 5-8, 10, 13-15, 17, 19]
, have focused,
predominantly on elliptical, rectangular (including square), and triangular configurations. Few detailed
measurements and simulations have been performed on the different coaxial jets were shown for other shapes [2-
3, 5-8, 10, 13-15, 17, 19]
.
The present study carried out the turbulence measurements of three jets issuing respectively from
Circular, Square and Hexagonal form orifice with equivalent hydraulic diameter. The main objective of the
present work is using the CFD results, to compare the turbulent flow fields of the three jets to identify their
similarity and difference.
II. DISCRIPTION OF THE PROBLEM
2.1. Fuel Injector
Fuel injection is a necessary component for all high performance engines because the fuel to air ratio
must be precisely controlled due to the extreme temperature and pressures found in high-compression turbo
engines. Combine this with large displacement and multiple cylinder power plants and the standard carburetor
arrangement simply cannot deliver a precisely controlled fuel-air mix to all cylinders simultaneously.
For smaller engines, inlet-port fuel injection can increase the power output of an engine by merely
reducing the temperature of the air charge, thereby increasing the density of the fuel and air mix. In most cases a
10 percent increase in power is achieved without any change to compression ratios or engine RPM; something a
carburetor just can’t do.
On engines where fuel is injected directly into the combustion chamber, the resulting spray pattern has a huge
impact on the burn rate of the charge and the usefulness of the expanding flame-front. Fuel injected in this
manner is better utilized if the entire combustion chamber is saturated with an atomized charge of fuel and air.
For this reason, some large diesel engines use nozzles with two to 16 separate holes designed to provide a spray
pattern that burns hotter and results in more complete combustion. Although efficient, the complexity of this
2. The CFD analysis of turbulence characteristics in combustion chamber with non circular co-axial jets
www.iosrjournals.org 2 | Page
system remains unsuitable for aviation use. However, the need for a consistent spray pattern — even from our
single-point nozzle — remains vitally important. Modeling of fuel injectors has been done in ANSYS design
modeler. Inner jet diameter is assumed and modeled for different shaped based on hydraulic diameter. Hydraulic
diameter is mathematically represented as follow:
𝑑ℎ =
4(𝐶𝑟𝑜𝑠𝑠 −𝑆𝑒𝑐𝑡𝑖𝑜𝑛𝑎𝑙 𝐴𝑟𝑒𝑎 )
𝑃𝑒𝑟𝑖𝑚𝑒𝑡𝑒𝑟
, mm. (1)
2.2 Combustion Chamber
The working fluid in the engine is heated by an internal combustion process. Before this chemical
reaction can occur, the liquid fuel must be injected into the airstream, atomized and the vapor must be mixed
with the air. Space is of course at a premium in aircraft applications, so that great effort is made to reduce the
size of the combustion chamber by hastening completion of the above processes. To keep engine size small, the
intensity of combustion (measured in, e.g. KJ/ m3
s) must be as high as possible. The combustion rate in gas
turbines at sea level is of the order of 500,000 kJ/m3
s, which is more than 100 times as intense as the
combustion in a large stationary power plant furnace. Part of the reason for the difference is that in the gas
turbine the density of the reactants is perhaps 10 times as high as in an atmospheric pressure furnace. Part of the
reason is the fineness of atomization of the injected fuel and another part is the intensity of the turbulence in a
typical gas turbine combustor. The more intense of turbulence leads to rapid mixing of the vaporized fuel and air
and the faster propagation of flame through the unburned mixture. Before considering typical designs of
combustors for air-breathing jet propulsion engines, we consider the combustion temperatures available with
typical fuels.
1.2.1. Combustion Temperature and Fuel –Air Ratio
Table 1 shows the properties of fuels commonly used in gas turbine combustors. Each fuel is a mixture
of hydrocarbon compounds, and the mixture composition is variable to some extent. Table 1 therefore provides
representative (rather than exact) properties typical of the mixtures that fall within the specification limits for
each fuel. JP – 4 fuel is relatively volatile and so has high vapor pressure.
JP – 4 and Jet A are widely used fuels for turbines. Aviation kerosene is not in plentiful supply.
For approximate calculation of fuel – air ratio and combustion temperature we can describe these
fuels as having hydrogen – carbon ratios of 2 and lower heating values (LHV) of 43,400 kJ/kg. Then, treating
the turbojet combustion process as through it were a heating process, we can write.
𝑚𝑓 𝑄 𝑅 = 𝑚 𝑎 𝐶𝑝 𝑇04 − 𝑇03 , (2)
Where 𝑚𝑓 is the fuel flow rate, 𝑚 𝑎 is the air flow rate, and 𝐶𝑝 is the specific heat at constant pressure. In terms
of the fuel – air ratio 𝑓 = 𝑚𝑓/𝑚 𝑎.
𝑓 =
𝐶 𝑝
𝑄 𝑅
𝑇04 − 𝑇03 . (3)
III. RESULTS AND DISCUSSION
Fuel injector diameter is taken as 8 mm for single jet. It has been modeled using ANSYS DESIGN
MODULAR. For coaxial circular jet, the diameter ratio (i.e. the ratio of the outer diameter to the inner diameter)
is considered as 2, and the inner diameter as 4mm. Then the circular coaxial jet is designed based on the above
values, in ANSYS DESIGN MODULAR as shown in figure 4.2.
To model non circular coaxial jets, inner cross section of the circular coaxial jet diameter is considered.
The different cross section of the noncircular diameter is calculated using equation 1 (i.e. hydraulic diameter is
ratio of 4 times of the cross sectional area to the perimeter). Based on this calculation, different models are
designed. Fuel injector is placed in the combustion chamber perpendicular to the central axis. Fuel inlet 1 and
fuel inlet 2 are mentioned on the basis of mass flow rate as calculated. Modeling of combustion chamber is done
based on the project report [28]
with small changes in secondary cooling ports and primary inlet diameter. Air is
passed through the primary inlet with the velocity of 25 m/s ( i.e. flow inside the combustion should have low
velocity for proper combustion).
3.1. Calculations
Molar volume for 1 mole of substance at 1 atm pressure and temperature 250
C. = 24.789 L/mol.
= 24.789 * 10-3
m3
/mol.
𝑉𝑚 =
𝑀
𝜌
m3
/mol. (4)
Where 𝑉𝑚 , M and 𝜌 are molar volume , molar weight and density respectively.
M = 58.12 g/mol. {for C4H10}
= 32 g/mol. {for O2}
3. The CFD analysis of turbulence characteristics in combustion chamber with non circular co-axial jets
www.iosrjournals.org 3 | Page
Assume pressure 1.5 bar for fuel injection and assume temp. 300 K
From combine gas law
𝑃1 𝑉 𝑚 1
𝑇1
=
𝑃2 𝑉 𝑚 2
𝑇2
(5)
Therefore;
1∗24.789∗10−3
298
=
1.5∗𝑉 𝑚 2
300
(6)
𝑉 𝑚2 = 0.0166 m3
/mol. =
58.12∗10−3
𝜌 𝐶4 𝐻10
(7)
𝜌 𝐶4 𝐻10
= 3.494 kg/m3
(8)
𝜌 𝑂2
= 1.9242 kg/m3
{because 0. 0166 m3
/mol. =
32∗10−3
𝜌 𝐶4 𝐻10
} (9)
Calculation of single jet mass flow rate:
𝑚𝑓 = 𝐴 ∗ 2 ∗ 𝑃 ∗ 𝜌 , kg/s. (10)
=
𝜋∗ 8∗10−3 2
4
∗ 2 ∗ 1.5 ∗ 105 ∗ 3.494 , kg/s.
= 0.05146, kg/s.
Calculation of Co-axial{circle -circle} jet mass flow rate:
𝑚𝑓 𝑂2
=
𝜋∗{ 8∗10−3 2
− 4.3∗10−3 2
}
4
∗ 2 ∗ 1.5 ∗ 105 ∗ 1.9242 , kg/s. (11)
= 0.0271 kg/s.
𝑚𝑓 𝐶4 𝐻10
=
𝜋 4∗10−3 2
4
∗ 2 ∗ 1.5 ∗ 105 ∗ 3.494 , kg/s. (12)
= 0.0128 kg/s.
Calculation of Co-axial {circle -square} jet mass flow rate:
𝑚𝑓 𝑂2
= {
𝜋∗{ 8∗10−3 2
}
4
− 4.3 ∗ 10−3 2
} ∗ 2 ∗ 1.5 ∗ 105 ∗ 1.9242 , kg/s. (13)
= 0.0241 kg/s.
𝑚𝑓 𝐶4 𝐻10
= 4 ∗ 10−3 2
∗ 2 ∗ 1.5 ∗ 105 ∗ 3.494 , kg/s. (14)
= 0.01638 kg/s.
Calculation of Co-axial {circle -hexagonal} jet mass flow rate:
𝑚𝑓 𝑂2
= {
𝜋∗{ 8∗10−3 2
}
4
−
3 3∗ 2.48∗10−3 2
2
} ∗ 2 ∗ 1.5 ∗ 105 ∗ 1.9242 , kg/s. (15)
= 0.02605 kg/s.
𝑚𝑓 𝐶4 𝐻10
=
3 3∗ 2.31∗10−3 2
2
∗ 2 ∗ 1.5 ∗ 105 ∗ 3.494 , kg/s. (16)
= 0.01419 kg/s ≈ 0.0142 kg/s.
After giving these parameters in CFX – Pre processer (Setup), results are obtained in the CFX – Post
processor (Result). From the result we found the values for velocity variations, turbulence kinetic energy,
turbulence eddy dissipation and etc. Variations of these parameters along the axial length are shown in chart 4.1,
4.2 and 4.3 respectively. We found that turbulence kinetic energy is more for noncircular coaxial (circle –
hexagonal) jet than circular coaxial jet and single jet (except circle – square cross section) . From above graphs
or charts we found that turbulence eddy dissipation is low for circle – square cross section when used as a fuel
injector as compared to circle – hexagonal and circle – circle.
Turbulence kinetic energy for circle – hexagonal fuel injector instead of circle – circle, circle – square,
and single jet shows 20.3% , 30.2 % ,and 85.9 % is more at the 0.06 cm of axial length respectively.
Turbulence eddy dissipation profile is shown in chart 4.3 along the axial length. It is found that
turbulence eddy dissipation of circle – hexagonal is high as compared to other coaxial jets as well as single jet
when they used as the fuel injectors. The percentage rise in turbulence eddy dissipation when used circle –
hexagonal shaped coaxial fuel injector as compared to others (proposed shapes are circle – circle ,circle – square
and single jets ) are 17.6% ,42.7% and 99.7% respectively.
4. The CFD analysis of turbulence characteristics in combustion chamber with non circular co-axial jets
www.iosrjournals.org 4 | Page
IV. FIGURES AND TABLES
Fig 4.1: Can type combustion chamber
Fig 4.2: Circle – Circle injector model
Fig 4.3: Circle – Square injector model
5. The CFD analysis of turbulence characteristics in combustion chamber with non circular co-axial jets
www.iosrjournals.org 5 | Page
Fig 4.4: Circle – hexagonal injector model
Fig 4.5: velocity variation in combustion chamber for circular co – axial fuel injector
Fig 4.6: velocity variation in combustion chamber for circle – square coaxial fuel injector
6. The CFD analysis of turbulence characteristics in combustion chamber with non circular co-axial jets
www.iosrjournals.org 6 | Page
Fig 4.7: velocity variation in combustion chamber for circle – hexagonal coaxial fuel
injector
Fig 4.8: Turbulence Kinetic Energy variation in combustion chamber for circular
coaxial fuel injector
Fig 4.9: Turbulence Kinetic Energy variation in combustion chamber for circle –square co – axial
fuel injector
7. The CFD analysis of turbulence characteristics in combustion chamber with non circular co-axial jets
www.iosrjournals.org 7 | Page
Fig 4.10: Turbulence Kinetic Energy variation in combustion chamber for
circle – hexagonal coaxial fuel injector
Table 4.1: Dimensions of Can type combustion chamber
S.No. Parameters Dimensions
1 H1 540 mm
2 H2 140 mm
3 H3 410 mm
4 H4 070 mm
5 H15 270 mm
6 H17 090 mm
7 D9 16 mm
8 D13 10 mm
9 D16 08 mm
10 L7 063 mm
11 L10 130 mm
12 L11 035 mm
13 L14 050 mm
Table 4.2: properties of fuel commonly used in gas turbines
S.No. Property Aviation
Kerosene
JP – 4 JP – 5 Jet A
1 H – C Ratio 1.93 2.02 1.92 1.94
2 Vapor press at 38o
C,
kPa.
18 0.3 0.7
3 Initial boiling point,
o
C.
50 60 180 170
4 End point,o
C 260 246 260 265
5 Flash point, o
C -25 65 52
6 L.H.V,kJ/kg 43,200 43,400 43,000 43,400
7 Density, kg/m3
800 760 820 810
8 Stoich,fuel – air mass
ratio
0.0679 0.0673 0.0680 0.0678
9 Stoich, air – fuel
mass ratio
14.72 14.85 14.71 14.74
8. The CFD analysis of turbulence characteristics in combustion chamber with non circular co-axial jets
www.iosrjournals.org 8 | Page
Chart 4.1: Velocity profile along axial length
Chart 4.2:turbulence kinetic energy profile along axial length
Chart 4.3:turbulence kinetic energy profile along axial length
V. CONCLUSION
Modeling of co–axial fuel injector (circular and non circular) based on hydraulic diameter of single jet
fuel injector of combustion chamber. Analysis on these modeled shapes has been done based on mass flow rate.
Obtained results shown a good turbulence kinetic energy in non – circular shape compared to circular shape
except circle – square one (proposed shapes). Turbulence characteristics such as turbulence eddy dissipation,
9. The CFD analysis of turbulence characteristics in combustion chamber with non circular co-axial jets
www.iosrjournals.org 9 | Page
turbulence kinetic energy, and velocity profiles are shown in above graph along the axial length. The main
drawback in this is it’s not providing good turbulence kinetic energy and turbulence eddy dissipation in Circle –
Square shape as compare with circular coaxial jet used as fuel injector. Where else Circle – Hexagonal shape
produce 20.3% and 17.6% more turbulence kinetic energy and turbulence eddy dissipation respectively than
circular coaxial jet.
ACKNOWLEDGEMENTS
It is a great pleasure to be able to show our faithful thanks to many people who helped and greatly supported us
during writing of this thesis.
First & foremost, I wish to express our utmost gratitude to our Chairperson Dr. ELLZABETH
VERGHESE & Dr. JOSEPH STANLEY, Director (Academic) for granting us to attend this project at
HINDUSTAN INSTITUTE OF TECHNOLOGY AND SCIENCE, CHENNAI.
I am grateful to Prof. NAGARAJAN M.E, (HOD) Department of Aeronautical engineering for his
encouragement, discussion and helpful attitude.
I extend our heartfelt gratitude goes to our Internal Guide Mr. P. MANIVANNAN, Asso. Prof. for his
technical contributions, valuable comments and many innovative ideas to carrying out this project. Without his
timely help it would have been impossible for us to complete this work.
I most sincerely acknowledge the staff members of Department of Aeronautical Engineering for their constant
inspiration and suggestions.
Last but not the least; I would like to thank my parents and my siblings for their support throughout my life.
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