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 Engineering Research and Development (IJERD)IJERD Editor
International Journal of Engineering Research and Development is an international premier peer reviewed open access engineering and technology journal promoting the discovery, innovation, advancement and dissemination of basic and transitional knowledge in engineering, technology and related disciplines.
Exergetic efficiency analysis of hydrogen–air detonation in pulse detonation ...BBIT Kolkata
Exergy losses during the combustion process, heat transfer, and fuel utilization play a vital role in the analysis of the
exergetic efficiency of combustion process. Detonation is thermodynamically more efficient than deflagration mode of
combustion. Detonation combustion technology inside the pulse detonation engine using hydrogen as a fuel is energetic
propulsion system for next generation. In this study, the main objective of this work is to quantify the exergetic efficiency
of hydrogen–air combustion for deflagration and detonation combustion process. Further detonation parameters are
calculated using 0.25, 0.35, and 0.55 of H2 mass concentrations in the combustion process. The simulations have been
performed for converging the solution using commercial computational fluid dynamics package Ansys Fluent solver. The
details of combustion physics in chemical reacting flows of hydrogen–air mixture in two control volumes were simulated
using species transport model with eddy dissipation turbulence chemistry interaction. From these simulations it was
observed that exergy loss in the deflagration combustion process is higher in comparison to the detonation combustion
process. The major observation was that pilot fuel economy for the two combustion processes and augmentation of
exergetic efficiencies are better in the detonation combustion process. The maximum exergetic efficiency of 55.12%,
53.19%, and 23.43% from deflagration combustion process and from detonation combustion process, 67.55%, 57.49%,
and 24.89%, are obtained from aforesaid H2 mass fraction. It was also found that for lesser fuel mass fraction higher
exergetic efficiency was observed.
Design Criteria for Optimization of the Cross Ignition Process in Gasturbine-...ijscmcj
Reducing of pollutants with simultaneous increase of the gas turbine power, is always a fundamental aim of the Turbine technology. New developed structures and operating systems in the turbine production have been established. In the meanwhile, burning instabilities are still appearing in these systems during a Cross-ignition process (CI), creating pollutants due to high flame temperatures, and are not yet completely investigated.The phenomena of a CI is taking place during operation of malty-burner combustion chambers, when one burner is extinguished and a particular volume of combustible mixture is formed in the distance between this burner and the adjacent lightened one, which considered to be as an ignition path. Cross ignition process should be performed along the ignition path in a particularly controlled small time.So that, no excessive quantities of combustible mixtures will be injected during this time in the combustion chamber. Otherwise, burning instabilities and mechanical wear will be occurred. Depending on this illustration, the Cross Ignition Time (CIT) of an extinguished burner, that will be considered as the evaluation measure for the entire cross-ignition process, should be Possibly as low as its normal ignition time.The main objective of this project is to reproduce constructive criteria for controlling of cross ignition process by influencing the mixing process and heat flux in a defined mixing zone existing along the ignition path.
DESIGN CRITERIA FOR OPTIMIZATION OF THE CROSS IGNITION PROCESS IN GASTURBINE-...ijscmcjournal
Reducing of pollutants with simultaneous increase of the gas turbine power, is always a fundamental aim
of the Turbine technology. New developed structures and operating systems in the turbine production have
been established. In the meanwhile, burning instabilities are still appearing in these systems during a
Cross-ignition process (CI), creating pollutants due to high flame temperatures, and are not yet completely
investigated.
The phenomena of a CI is taking place during operation of malty-burner combustion chambers, when one
burner is extinguished and a particular volume of combustible mixture is formed in the distance between
this burner and the adjacent lightened one, which considered to be as an ignition path.
Cross ignition process should be performed along the ignition path in a particularly controlled small time.
So that, no excessive quantities of combustible mixtures will be injected during this time in the combustion
chamber. Otherwise, burning instabilities and mechanical wear will be occurred.
Depending on this illustration, the Cross Ignition Time (CIT) of an extinguished burner, that will be
considered as the evaluation measure for the entire cross-ignition process, should be Possibly as low as its
normal ignition time.
The main objective of this project is to reproduce constructive criteria for controlling of cross ignition
process by influencing the mixing process and heat flux in a defined mixing zone existing along the ignition
path.
Optimizing Bunsen burner Performance Using CFD AnalysisIJMER
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 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.
The fuel-air cycle provides a more accurate model of the actual thermodynamic cycle in an internal combustion engine compared to the air standard cycle by accounting for:
1) The actual composition of gases in the cylinder, which varies throughout the cycle.
2) Variations in specific heat and dissociation effects at high temperatures.
3) Changes in the number of moles as pressure and temperature fluctuate.
The fuel-air cycle shows that efficiency is maximized with a slightly rich mixture near stoichiometric due to higher temperatures from dissociation. It also demonstrates efficiency gains from higher compression but losses from richer mixtures beyond stoichiometric due to incomplete combustion.
This document discusses various thermodynamic cycles used in power generation applications including vapor power cycles, gas power cycles, and gas turbine cycles. It describes the basic processes and assumptions of cycles like the Rankine, Otto, diesel, and Brayton cycles. Methods to improve the performance of these cycles are also covered, such as increasing boiler pressure, superheating, reheating, and regeneration. The key applications of thermodynamics discussed are steam power plants, internal combustion engines, and gas turbine engines.
International Journal of Engineering Research and Development (IJERD)IJERD Editor
International Journal of Engineering Research and Development is an international premier peer reviewed open access engineering and technology journal promoting the discovery, innovation, advancement and dissemination of basic and transitional knowledge in engineering, technology and related disciplines.
Exergetic efficiency analysis of hydrogen–air detonation in pulse detonation ...BBIT Kolkata
Exergy losses during the combustion process, heat transfer, and fuel utilization play a vital role in the analysis of the
exergetic efficiency of combustion process. Detonation is thermodynamically more efficient than deflagration mode of
combustion. Detonation combustion technology inside the pulse detonation engine using hydrogen as a fuel is energetic
propulsion system for next generation. In this study, the main objective of this work is to quantify the exergetic efficiency
of hydrogen–air combustion for deflagration and detonation combustion process. Further detonation parameters are
calculated using 0.25, 0.35, and 0.55 of H2 mass concentrations in the combustion process. The simulations have been
performed for converging the solution using commercial computational fluid dynamics package Ansys Fluent solver. The
details of combustion physics in chemical reacting flows of hydrogen–air mixture in two control volumes were simulated
using species transport model with eddy dissipation turbulence chemistry interaction. From these simulations it was
observed that exergy loss in the deflagration combustion process is higher in comparison to the detonation combustion
process. The major observation was that pilot fuel economy for the two combustion processes and augmentation of
exergetic efficiencies are better in the detonation combustion process. The maximum exergetic efficiency of 55.12%,
53.19%, and 23.43% from deflagration combustion process and from detonation combustion process, 67.55%, 57.49%,
and 24.89%, are obtained from aforesaid H2 mass fraction. It was also found that for lesser fuel mass fraction higher
exergetic efficiency was observed.
Design Criteria for Optimization of the Cross Ignition Process in Gasturbine-...ijscmcj
Reducing of pollutants with simultaneous increase of the gas turbine power, is always a fundamental aim of the Turbine technology. New developed structures and operating systems in the turbine production have been established. In the meanwhile, burning instabilities are still appearing in these systems during a Cross-ignition process (CI), creating pollutants due to high flame temperatures, and are not yet completely investigated.The phenomena of a CI is taking place during operation of malty-burner combustion chambers, when one burner is extinguished and a particular volume of combustible mixture is formed in the distance between this burner and the adjacent lightened one, which considered to be as an ignition path. Cross ignition process should be performed along the ignition path in a particularly controlled small time.So that, no excessive quantities of combustible mixtures will be injected during this time in the combustion chamber. Otherwise, burning instabilities and mechanical wear will be occurred. Depending on this illustration, the Cross Ignition Time (CIT) of an extinguished burner, that will be considered as the evaluation measure for the entire cross-ignition process, should be Possibly as low as its normal ignition time.The main objective of this project is to reproduce constructive criteria for controlling of cross ignition process by influencing the mixing process and heat flux in a defined mixing zone existing along the ignition path.
DESIGN CRITERIA FOR OPTIMIZATION OF THE CROSS IGNITION PROCESS IN GASTURBINE-...ijscmcjournal
Reducing of pollutants with simultaneous increase of the gas turbine power, is always a fundamental aim
of the Turbine technology. New developed structures and operating systems in the turbine production have
been established. In the meanwhile, burning instabilities are still appearing in these systems during a
Cross-ignition process (CI), creating pollutants due to high flame temperatures, and are not yet completely
investigated.
The phenomena of a CI is taking place during operation of malty-burner combustion chambers, when one
burner is extinguished and a particular volume of combustible mixture is formed in the distance between
this burner and the adjacent lightened one, which considered to be as an ignition path.
Cross ignition process should be performed along the ignition path in a particularly controlled small time.
So that, no excessive quantities of combustible mixtures will be injected during this time in the combustion
chamber. Otherwise, burning instabilities and mechanical wear will be occurred.
Depending on this illustration, the Cross Ignition Time (CIT) of an extinguished burner, that will be
considered as the evaluation measure for the entire cross-ignition process, should be Possibly as low as its
normal ignition time.
The main objective of this project is to reproduce constructive criteria for controlling of cross ignition
process by influencing the mixing process and heat flux in a defined mixing zone existing along the ignition
path.
Optimizing Bunsen burner Performance Using CFD AnalysisIJMER
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 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.
The fuel-air cycle provides a more accurate model of the actual thermodynamic cycle in an internal combustion engine compared to the air standard cycle by accounting for:
1) The actual composition of gases in the cylinder, which varies throughout the cycle.
2) Variations in specific heat and dissociation effects at high temperatures.
3) Changes in the number of moles as pressure and temperature fluctuate.
The fuel-air cycle shows that efficiency is maximized with a slightly rich mixture near stoichiometric due to higher temperatures from dissociation. It also demonstrates efficiency gains from higher compression but losses from richer mixtures beyond stoichiometric due to incomplete combustion.
This document discusses various thermodynamic cycles used in power generation applications including vapor power cycles, gas power cycles, and gas turbine cycles. It describes the basic processes and assumptions of cycles like the Rankine, Otto, diesel, and Brayton cycles. Methods to improve the performance of these cycles are also covered, such as increasing boiler pressure, superheating, reheating, and regeneration. The key applications of thermodynamics discussed are steam power plants, internal combustion engines, and gas turbine engines.
Actual cycles for internal combustion engines differ from air-standard cycles in many respects.
Time loss factor.
Heat loss factor.
Exhaust blow down factor.
Investigation on multi cylinder s.i engine using blends of hydrogen and cngeSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
An experimental and kinetic study of syngas-air combustion at elevated temper...Saad Tanvir
This document describes an experimental study of syngas combustion at elevated temperatures and the effect of adding water. Laminar flame speeds of syngas/air mixtures were measured over a range of fuel compositions, equivalence ratios, and preheat temperatures. The measured flame speeds were compared to simulations from existing chemical kinetic models, showing reasonable agreement at room temperature but large discrepancies at higher temperatures. Water was added to two syngas fuels up to 40% by volume, and different effects on flame speed were observed depending on the fuel composition and water concentration, related to competing chemical and physical impacts of water addition.
IRJET- Experimental Investigation on Effect of Chemical Composition on Stabil...IRJET Journal
This document describes an experimental investigation into the effect of chemical composition on the stability of premixed gas flames. The researchers analyzed the flame structure and stability of LPG-air and methane-air mixtures over a wide range of equivalence ratios (Φ) and Reynolds numbers (Re). They found that the flame structure and stability depended mainly on Φ and Re. The flame height increased as Φ increased beyond 1 to 1.8. The flame remained laminar up to Re=1500, after which it became turbulent. Flame height increased with Re but flame structure did not change. The researchers modified an existing round burner design to create a slot burner and compared flame results between the two burner types for different gases.
A REVIEW PAPER ON EXPERIMENTAL AND NUMERICAL INVESTIGATION OF PARAMETRIC STUD...ijsrd.com
Flame is an important parameter for any combustion process which is responsible for either the complete or incomplete combustion process. There are certain factors which influence the flame length and diameter such as fire source diameter or nozzle diameter, equivalence ratio, quality of fuel, heat release rate etc. Investigation of flame length and diameter is more relevance in the rational design of combustion chamber, be it for an internal engine or for a furnace. The flame represents the zone of combustion, its length is a measure of the intensity of combustion and therefore of heat release. So, this paper reviews about the flame behavior on the basis of flame length and diameter.
The document discusses various air standard cycles that are used to model internal combustion engine processes, including the Otto, Diesel, and dual cycles. It provides details on the assumptions and thermodynamic processes that define each cycle. The Otto cycle consists of four processes: constant-pressure intake, isentropic compression, constant-volume combustion, and isentropic expansion. The Diesel cycle models combustion as a constant-pressure process rather than constant volume. The dual cycle models combustion as both constant-volume and constant-pressure processes. Comparisons are made between the cycles in terms of their heat transfer and thermal efficiencies.
Energy performance assessment of boilersUtsav Jain
The document discusses performance testing of boilers. It describes various factors that affect boiler performance over time such as poor combustion, heat transfer fouling, and deteriorated fuel and water quality. Boiler efficiency testing is important to evaluate how efficiency changes from the design value and identify problems. The direct method and indirect method of testing are described. The indirect method involves calculating different heat losses in the boiler system to determine efficiency. Various measurements, instruments, test conditions and computational procedures for conducting boiler performance tests are outlined.
Effect of Ambient Temperature and Composition on Liquid Droplet CombustionIJERA Editor
An unsteady, spherically symmetric, single component, diffusion controlled gas phase droplet combustion
model was developed assuming infinite kinetics and no radiation effects. Finite difference technique was used to
solve time dependent equations of energy and species. Adiabatic flame temperature which is important for
calculating thermodynamic properties was calculated by employing a detailed method. Effects of ambient
temperature and composition on important combustion parameters like adiabatic flame temperature, droplet
mass burning rate, burning constant and droplet lifetime were obtained. Results indicated that flame
temperature, burning constant and mass burning rate increased with an increase in ambient temperature while
the droplet life time decreased. The present gas phase code was used in conjunction with the Olikara and
Borman code for obtaining concentration of important species. Emission results showed that for a 100m nheptane
droplet burning in standard atmosphere, an increase in ambient temperature led to an increase in NO
and CO concentrations and a decrease in CO2 and H2O concentrations. Extinction diameter for a 3000m nheptane
droplet burning in oxygen-helium environment was determined. Also, effects of ambient temperature
and composition were obtained on droplet lifetime and mass burning rate as a function of initial droplet
diameter. The present gas phase model is simple but realistic and can be incorporated in spray combustion
codes.
EXPERIMENTAL INVESTIGATION ON THERMAL PERFORMANCE OF POROUS RADIANT BURNER AN...BIBHUTI BHUSAN SAMANTARAY
This paper presents the heat transfer characteristics of a
self-aspirating porous radiant burner (SAPRB) that operates
on the basis of an effective energy conversion method between
flowing gas enthalpy and thermal radiation. The temperature
field at various flame zones was measured experimentally by
the help of both FLUKE IR camera and K-type thermocouples.
The experimental setup consisted of a two layered domestic
cooking burner, a flexible test stand attached with six K-type
thermocouples at different positions, IR camera, LPG setup
and a hot wire anemometer. The two layered SAPRB consisted
of a combustion zone and a preheating zone. Combustion zone
was formed with high porosity, highly radiating porous
matrix, and the preheating zone consisted of low porosity
matrix. Time dependent temperature history from
thermocouples at various flame zones were acquired by using
a data acquisition system and the temperature profiles were
analyzed in the ZAILA application software environments. In
the other hand the IR graphs were captured by FLUKE IR
camera and the thermographs were analyzed in the
SMARTView software environments. The experimental results
revealed that the homogeneous porous media, in addition to
its convective heat exchange with the gas, might absorb, emit,
and scatter thermal radiation. The rate of heat transfer was
more at the center of the burner where a combined effect of
both convection & radiation might be realized. The maximum
thermal efficiency was found to be 64% which was having a
good agreement with the previous data in the open literature.
This presentation was prepared by Mechanical Engineering students during their Internal Combustion Course. Students belong to a very prestigious Engineering institute of Pakistan "University of Engineering and Technology Lahore"
Estimating The Available Amount Of Waste Heatharlandmachacon
The document estimates the available waste heat from the flue gases of an asphalt dispenser machine used in a dry cell manufacturing plant. The machine uses LPG burners to melt asphalt and seal dry cells. Hot flue gases from combustion are currently exhausted and lost. The study aims to quantify this waste heat for potential recovery. It outlines the machine's operation, describes the flue gas properties, and presents equations to calculate the gas temperature reduction possible before condensation and the resulting recoverable sensible heat.
An experimental study on kerosene based pulse detonation engineIAEME Publication
This document summarizes an experimental study on a kerosene-based pulse detonation engine. The study tested three equivalence ratios of kerosene and air mixtures. Pressure measurements at different locations along the detonation tube are presented and compared to theoretical Chapman-Jouguet detonation pressures from a NASA chemical equilibrium program. For equivalence ratios of 1.0 and 1.14, the pressure measurements indicate a deflagration to detonation transition occurred before the second measurement location, matching detonation pressures. This confirms stable detonation was achieved in the pulse detonation engine setup.
This document discusses different types of flames including premixed and diffusion flames. It defines a flame as a thermal wave where rapid exothermic chemical reactions occur and travel at subsonic velocities. Premixed flames involve fuel and air mixtures that burn, while diffusion flames involve separate introduction of fuel and air that mix and burn. The structure of laminar premixed flames is also examined, including temperature and concentration gradients across the combustion wave and factors affecting flame shape.
This document summarizes a student group project to design a Rankine cycle steam turbine power plant with the goal of achieving over 31% thermal efficiency. Three design trials are presented with varying turbine outlet pressures and temperatures. Trial 3 achieved the highest efficiency of 32.12% with a turbine outlet of 57.02°C and 17.5kPa. Key parameters like turbine inlet/outlet conditions and pump properties are discussed. While the goals were met, the summary notes real-world factors like material degradation were not considered, demonstrating the complexity of efficient steam turbine design.
This document analyzes the performance of a regenerative steam system in a thermal power plant and proposes modifications to improve turbine efficiency. Currently, cascading only occurs between high pressure and low pressure heaters separately, wasting heat to the deaerator. The proposal involves cascading all heaters together to utilize waste heat in low pressure heaters. Taking extraction steam at the high pressure turbine outlet instead of the boiler outlet could also increase turbine work and efficiency. Analysis estimates increasing heater coils could lower drip temperatures enough for cascading, recovering over 29,000 kW of heat annually and raising plant efficiency by 3%.
Natural draught is produced by a chimney and provides ventilation for boiler systems. The height and diameter of a chimney can be calculated based on factors like flue gas temperature, ambient temperature, and air-fuel ratio. For maximum discharge of hot gases, the flue gas temperature should be slightly higher than ambient temperature. Chimneys provide advantages like no external power requirements but have limitations like low efficiency below 1%. Boiler performance is quantified by equivalent evaporation and efficiency, which allow standardization based on feed water temperature and pressure.
This document presents a theoretical analysis of the performance of a vapor compression refrigeration system using different refrigerants: R-12, R134a, and R1234yf. The analysis uses a computational model based on the first law of thermodynamics to investigate the effects of evaporating temperature, subcooling, condenser temperature, and liquid-vapor heat exchanger effectiveness on the system's coefficient of performance and refrigerating capacity. The results show that R1234yf has the highest relative capacity increase with increased subcooling and the highest percentage increase in COP. R134a requires the most compressor work. R1234yf is identified as a promising alternative to R134a due to its low global warming potential
Simulation Studies Of Premixed N-Pentane/Air Liquid Micro CombustionIJERA Editor
With latest improvements in MEMS, combustion based Micro-Power generation devices are seen as alternatives for conventional batteries because of the high energy densities of Hydrogen and other hydrocarbon fuels. An important feature of micro-power system is to utilize the combustion of fuel or propellant in the micro-burner to produce the gas with high temperature and high pressure to drive turbines or other power units, which convert chemical into energy directly or indirectly other forms of energy, for example heat or power. We have concentrated on the usage of Micro combustion as a substitute for conventional batteries .In our study, a Micro Combustor of 1mm x 10mm is taken for Numerical Study. Combustion characteristics of N Pentane-Air mixture in a planar micro-channel is studied numerically. We have performed the liquid fuel combustion of n-Pentane and air to study the effects of liquid fuel combustion in a micro channel. The effect of axial velocity inlet, on exhaust gas temperature and Hydrogen Peroxide addition on exhaust gas concentration was analyzed respectively. We also investigated numerically the combustion characteristics under different conditions such as by varying the DPM, Number of Fuel Streams, and Spray Angle and so on. For this numerical analysis, an experimental model is considered as reference, and the geometry and the boundary conditions are taken from it for the purpose of simulation. In this study, n-Pentane is introduced as liquid droplets at the centerline and the liquid combustion is simulated numerically.
How to get the combustible stability of the flame.
As well as reducing polluting emissions to the environment.
Work on designing modern combustion burner techniques to avoid combustion problems.
A REVIEW PAPER ON EXPERIMENTAL AND NUMERICAL INVESTIGATION OF PARAMETRIC STUD...ijsrd.com
Combustion phenomena related to Froude number and Stroukal number were investigated in diffusion flames under various gravity levels. The Froude number of the fuel was controlled by gravity level, diameter of the nozzle, and fluid flow rate. Theoretical analysis is presented to laneway flame length model based on dimensional analyses. Analysis results indicate that flame length relates to heat release rate, fire source diameter, combustible matter diffusivity, etc. Based on Similarity principle, the laneway fire experiment plant has been setup. And using a video camera, the data of the experiment is recorded. Experiment results indicate that flame length is directly proportional to heat release rate, fire source diameter and combustible matter diffusivity. And a semi-empirical formula on flame length has been got using the least-square program to fit the experimental data. The results are of importance for flame radiation calculation and fire risk analysis. Flame is an important parameter for any combustion process which is responsible for either the complete or incomplete combustion process. There are certain factors which influence the flame length and diameter such as fire source diameter or nozzle diameter, equivalence ratio, quality of fuel, heat release rate etc. Investigation of flame length and diameter is more relevance in the rational design of combustion chamber, be it for an internal engine or for a furnace. The flame represents the zone of combustion, its length is a measure of the intensity of combustion and therefore of heat release. So, this paper reviews about the flame behavior on the basis of flame length and diameter.
Actual cycles for internal combustion engines differ from air-standard cycles in many respects.
Time loss factor.
Heat loss factor.
Exhaust blow down factor.
Investigation on multi cylinder s.i engine using blends of hydrogen and cngeSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
An experimental and kinetic study of syngas-air combustion at elevated temper...Saad Tanvir
This document describes an experimental study of syngas combustion at elevated temperatures and the effect of adding water. Laminar flame speeds of syngas/air mixtures were measured over a range of fuel compositions, equivalence ratios, and preheat temperatures. The measured flame speeds were compared to simulations from existing chemical kinetic models, showing reasonable agreement at room temperature but large discrepancies at higher temperatures. Water was added to two syngas fuels up to 40% by volume, and different effects on flame speed were observed depending on the fuel composition and water concentration, related to competing chemical and physical impacts of water addition.
IRJET- Experimental Investigation on Effect of Chemical Composition on Stabil...IRJET Journal
This document describes an experimental investigation into the effect of chemical composition on the stability of premixed gas flames. The researchers analyzed the flame structure and stability of LPG-air and methane-air mixtures over a wide range of equivalence ratios (Φ) and Reynolds numbers (Re). They found that the flame structure and stability depended mainly on Φ and Re. The flame height increased as Φ increased beyond 1 to 1.8. The flame remained laminar up to Re=1500, after which it became turbulent. Flame height increased with Re but flame structure did not change. The researchers modified an existing round burner design to create a slot burner and compared flame results between the two burner types for different gases.
A REVIEW PAPER ON EXPERIMENTAL AND NUMERICAL INVESTIGATION OF PARAMETRIC STUD...ijsrd.com
Flame is an important parameter for any combustion process which is responsible for either the complete or incomplete combustion process. There are certain factors which influence the flame length and diameter such as fire source diameter or nozzle diameter, equivalence ratio, quality of fuel, heat release rate etc. Investigation of flame length and diameter is more relevance in the rational design of combustion chamber, be it for an internal engine or for a furnace. The flame represents the zone of combustion, its length is a measure of the intensity of combustion and therefore of heat release. So, this paper reviews about the flame behavior on the basis of flame length and diameter.
The document discusses various air standard cycles that are used to model internal combustion engine processes, including the Otto, Diesel, and dual cycles. It provides details on the assumptions and thermodynamic processes that define each cycle. The Otto cycle consists of four processes: constant-pressure intake, isentropic compression, constant-volume combustion, and isentropic expansion. The Diesel cycle models combustion as a constant-pressure process rather than constant volume. The dual cycle models combustion as both constant-volume and constant-pressure processes. Comparisons are made between the cycles in terms of their heat transfer and thermal efficiencies.
Energy performance assessment of boilersUtsav Jain
The document discusses performance testing of boilers. It describes various factors that affect boiler performance over time such as poor combustion, heat transfer fouling, and deteriorated fuel and water quality. Boiler efficiency testing is important to evaluate how efficiency changes from the design value and identify problems. The direct method and indirect method of testing are described. The indirect method involves calculating different heat losses in the boiler system to determine efficiency. Various measurements, instruments, test conditions and computational procedures for conducting boiler performance tests are outlined.
Effect of Ambient Temperature and Composition on Liquid Droplet CombustionIJERA Editor
An unsteady, spherically symmetric, single component, diffusion controlled gas phase droplet combustion
model was developed assuming infinite kinetics and no radiation effects. Finite difference technique was used to
solve time dependent equations of energy and species. Adiabatic flame temperature which is important for
calculating thermodynamic properties was calculated by employing a detailed method. Effects of ambient
temperature and composition on important combustion parameters like adiabatic flame temperature, droplet
mass burning rate, burning constant and droplet lifetime were obtained. Results indicated that flame
temperature, burning constant and mass burning rate increased with an increase in ambient temperature while
the droplet life time decreased. The present gas phase code was used in conjunction with the Olikara and
Borman code for obtaining concentration of important species. Emission results showed that for a 100m nheptane
droplet burning in standard atmosphere, an increase in ambient temperature led to an increase in NO
and CO concentrations and a decrease in CO2 and H2O concentrations. Extinction diameter for a 3000m nheptane
droplet burning in oxygen-helium environment was determined. Also, effects of ambient temperature
and composition were obtained on droplet lifetime and mass burning rate as a function of initial droplet
diameter. The present gas phase model is simple but realistic and can be incorporated in spray combustion
codes.
EXPERIMENTAL INVESTIGATION ON THERMAL PERFORMANCE OF POROUS RADIANT BURNER AN...BIBHUTI BHUSAN SAMANTARAY
This paper presents the heat transfer characteristics of a
self-aspirating porous radiant burner (SAPRB) that operates
on the basis of an effective energy conversion method between
flowing gas enthalpy and thermal radiation. The temperature
field at various flame zones was measured experimentally by
the help of both FLUKE IR camera and K-type thermocouples.
The experimental setup consisted of a two layered domestic
cooking burner, a flexible test stand attached with six K-type
thermocouples at different positions, IR camera, LPG setup
and a hot wire anemometer. The two layered SAPRB consisted
of a combustion zone and a preheating zone. Combustion zone
was formed with high porosity, highly radiating porous
matrix, and the preheating zone consisted of low porosity
matrix. Time dependent temperature history from
thermocouples at various flame zones were acquired by using
a data acquisition system and the temperature profiles were
analyzed in the ZAILA application software environments. In
the other hand the IR graphs were captured by FLUKE IR
camera and the thermographs were analyzed in the
SMARTView software environments. The experimental results
revealed that the homogeneous porous media, in addition to
its convective heat exchange with the gas, might absorb, emit,
and scatter thermal radiation. The rate of heat transfer was
more at the center of the burner where a combined effect of
both convection & radiation might be realized. The maximum
thermal efficiency was found to be 64% which was having a
good agreement with the previous data in the open literature.
This presentation was prepared by Mechanical Engineering students during their Internal Combustion Course. Students belong to a very prestigious Engineering institute of Pakistan "University of Engineering and Technology Lahore"
Estimating The Available Amount Of Waste Heatharlandmachacon
The document estimates the available waste heat from the flue gases of an asphalt dispenser machine used in a dry cell manufacturing plant. The machine uses LPG burners to melt asphalt and seal dry cells. Hot flue gases from combustion are currently exhausted and lost. The study aims to quantify this waste heat for potential recovery. It outlines the machine's operation, describes the flue gas properties, and presents equations to calculate the gas temperature reduction possible before condensation and the resulting recoverable sensible heat.
An experimental study on kerosene based pulse detonation engineIAEME Publication
This document summarizes an experimental study on a kerosene-based pulse detonation engine. The study tested three equivalence ratios of kerosene and air mixtures. Pressure measurements at different locations along the detonation tube are presented and compared to theoretical Chapman-Jouguet detonation pressures from a NASA chemical equilibrium program. For equivalence ratios of 1.0 and 1.14, the pressure measurements indicate a deflagration to detonation transition occurred before the second measurement location, matching detonation pressures. This confirms stable detonation was achieved in the pulse detonation engine setup.
This document discusses different types of flames including premixed and diffusion flames. It defines a flame as a thermal wave where rapid exothermic chemical reactions occur and travel at subsonic velocities. Premixed flames involve fuel and air mixtures that burn, while diffusion flames involve separate introduction of fuel and air that mix and burn. The structure of laminar premixed flames is also examined, including temperature and concentration gradients across the combustion wave and factors affecting flame shape.
This document summarizes a student group project to design a Rankine cycle steam turbine power plant with the goal of achieving over 31% thermal efficiency. Three design trials are presented with varying turbine outlet pressures and temperatures. Trial 3 achieved the highest efficiency of 32.12% with a turbine outlet of 57.02°C and 17.5kPa. Key parameters like turbine inlet/outlet conditions and pump properties are discussed. While the goals were met, the summary notes real-world factors like material degradation were not considered, demonstrating the complexity of efficient steam turbine design.
This document analyzes the performance of a regenerative steam system in a thermal power plant and proposes modifications to improve turbine efficiency. Currently, cascading only occurs between high pressure and low pressure heaters separately, wasting heat to the deaerator. The proposal involves cascading all heaters together to utilize waste heat in low pressure heaters. Taking extraction steam at the high pressure turbine outlet instead of the boiler outlet could also increase turbine work and efficiency. Analysis estimates increasing heater coils could lower drip temperatures enough for cascading, recovering over 29,000 kW of heat annually and raising plant efficiency by 3%.
Natural draught is produced by a chimney and provides ventilation for boiler systems. The height and diameter of a chimney can be calculated based on factors like flue gas temperature, ambient temperature, and air-fuel ratio. For maximum discharge of hot gases, the flue gas temperature should be slightly higher than ambient temperature. Chimneys provide advantages like no external power requirements but have limitations like low efficiency below 1%. Boiler performance is quantified by equivalent evaporation and efficiency, which allow standardization based on feed water temperature and pressure.
This document presents a theoretical analysis of the performance of a vapor compression refrigeration system using different refrigerants: R-12, R134a, and R1234yf. The analysis uses a computational model based on the first law of thermodynamics to investigate the effects of evaporating temperature, subcooling, condenser temperature, and liquid-vapor heat exchanger effectiveness on the system's coefficient of performance and refrigerating capacity. The results show that R1234yf has the highest relative capacity increase with increased subcooling and the highest percentage increase in COP. R134a requires the most compressor work. R1234yf is identified as a promising alternative to R134a due to its low global warming potential
Simulation Studies Of Premixed N-Pentane/Air Liquid Micro CombustionIJERA Editor
With latest improvements in MEMS, combustion based Micro-Power generation devices are seen as alternatives for conventional batteries because of the high energy densities of Hydrogen and other hydrocarbon fuels. An important feature of micro-power system is to utilize the combustion of fuel or propellant in the micro-burner to produce the gas with high temperature and high pressure to drive turbines or other power units, which convert chemical into energy directly or indirectly other forms of energy, for example heat or power. We have concentrated on the usage of Micro combustion as a substitute for conventional batteries .In our study, a Micro Combustor of 1mm x 10mm is taken for Numerical Study. Combustion characteristics of N Pentane-Air mixture in a planar micro-channel is studied numerically. We have performed the liquid fuel combustion of n-Pentane and air to study the effects of liquid fuel combustion in a micro channel. The effect of axial velocity inlet, on exhaust gas temperature and Hydrogen Peroxide addition on exhaust gas concentration was analyzed respectively. We also investigated numerically the combustion characteristics under different conditions such as by varying the DPM, Number of Fuel Streams, and Spray Angle and so on. For this numerical analysis, an experimental model is considered as reference, and the geometry and the boundary conditions are taken from it for the purpose of simulation. In this study, n-Pentane is introduced as liquid droplets at the centerline and the liquid combustion is simulated numerically.
How to get the combustible stability of the flame.
As well as reducing polluting emissions to the environment.
Work on designing modern combustion burner techniques to avoid combustion problems.
A REVIEW PAPER ON EXPERIMENTAL AND NUMERICAL INVESTIGATION OF PARAMETRIC STUD...ijsrd.com
Combustion phenomena related to Froude number and Stroukal number were investigated in diffusion flames under various gravity levels. The Froude number of the fuel was controlled by gravity level, diameter of the nozzle, and fluid flow rate. Theoretical analysis is presented to laneway flame length model based on dimensional analyses. Analysis results indicate that flame length relates to heat release rate, fire source diameter, combustible matter diffusivity, etc. Based on Similarity principle, the laneway fire experiment plant has been setup. And using a video camera, the data of the experiment is recorded. Experiment results indicate that flame length is directly proportional to heat release rate, fire source diameter and combustible matter diffusivity. And a semi-empirical formula on flame length has been got using the least-square program to fit the experimental data. The results are of importance for flame radiation calculation and fire risk analysis. Flame is an important parameter for any combustion process which is responsible for either the complete or incomplete combustion process. There are certain factors which influence the flame length and diameter such as fire source diameter or nozzle diameter, equivalence ratio, quality of fuel, heat release rate etc. Investigation of flame length and diameter is more relevance in the rational design of combustion chamber, be it for an internal engine or for a furnace. The flame represents the zone of combustion, its length is a measure of the intensity of combustion and therefore of heat release. So, this paper reviews about the flame behavior on the basis of flame length and diameter.
Combustion in an SI engine occurs in three stages:
1. The ignition lag stage is the delay between the spark and noticeable pressure rise from combustion. This allows the fuel-air mixture to heat up to its self-ignition temperature.
2. In the flame propagation stage, the flame front travels across the combustion chamber, releasing energy and increasing pressure.
3. The afterburning stage finishes combusting any remaining unburnt fuel-air mixture after the flame front passes.
An Experimental Study of the Effect of Partial Premixing Level on the Interac...Waqas Tariq
Flame kernels in spark-ignited combustion systems dominate the flame propagation and combustion stability, performance and emissions. The aim of the present work is to investigate the flow field associated with flame kernel propagation history in partial premixing natural gas turbulent flames. The main parameters under investigation are the degree of partial premixing and jet velocity. Three different degrees of partial premixing and five values of jet velocity between10 and 20 m/s have been selected for the present work at an equivalence ratio of 2. The mean flow field and turbulence intensity are measured using two-dimensional Planar Imaging Velocimetry (PIV). A pulsed Nd: YAG laser is used for flame ignition. The turbulent flow field is captured after the ignition at several time intervals between, 150, and 2500 ?s after ignition. The results show that the flame kernel does not show any significant effect on the scale of mean flow field. On the other hand, the flame kernel increases the global turbulence intensity in flames in comparison with the isothermal cases. The flame kernel propagation is associated with a steep increase in the centerline turbulence intensity of the jet flow. An increase in the degree of partial premixing and/or the jet velocity increases the centerline turbulence intensity accompanying the flame kernel propagation. This leads to break-up of the degree of partial premixing of the flame structure, and hence, decreased flame stability. Also, the higher the degree of partial premixing or the higher the jet velocity leads to more rapid flame kernel extinction. The results show that the rate of flame kernel propagation is very fast at the early stage of the kernel propagation up to the first 300 ?s and then it slows down afterwards.
Experimental Investigation of Flame Kernel in Turbulent Partial Premixed FlamesWaqas Tariq
The flame kernel propagation is believed to be influenced by many operating parameters such as mixing level, turbulent intensity, and the mixture equivalence ratio. The purpose of this study is to investigate the effect of the mixture equivalence ratio and turbulence intensity on the flame kernel and flow field interlinks in partially premixed natural gas flames. Three jet equivalence ratios of 1, 1.5, and 2 are considered at values of jet velocities in the range from 10 to 20 m/s. This study was done under constant degree of partial premixing. A pulsed Nd: YAG laser is used for the flame ignition, and the turbulent flow field is captured at several time intervals from ignition using two-dimensional Planar Imaging Velocimetry (PIV). The mean flow field doesn’t influence with the flame kernel propagation. The turbulent flow field indicates an increase in the global turbulence intensity in flames associated with the kernel propagation in comparison with the isothermal case. The jet equivalence ratio of one enhances the flame kernel propagation and it gives the highest rate of kernel propagation. Increasing the jet equivalence ratio to 1.5 and 2 reduces the intensity of chemical reaction and hence the effect of turbulence becomes the dominant factor effecting the propagation of the flame kernel .At jet velocity of 20 m/s , an early flame kernel extinction is recorded without any respect to jet equivalence ratio. At the early stage of the kernel generation at delay time of 150 ?s, linear correlation between the jet velocity and the kernel propagation is noticed. The chemical reaction is the main factor influences the rate of kernel propagation; it gives nearly 3.5 times the effect of the flow convection to the maximum rate of the flame kernel propagation at jet velocity of 20 m/s and equivalence ratio of one.
5+ combustion and combustion chamber for si enginesFasilMelese
Combustion in spark ignition engines can occur via homogeneous or heterogeneous mixtures. In a homogeneous mixture, combustion occurs in three stages: an initial delay period, a flame propagation period where pressure rises rapidly, and a final quenching period. Factors that influence the flame speed include turbulence, fuel-air ratio, temperature/pressure, compression ratio, engine output, and engine speed. Abnormal combustion in the form of knock or surface ignition can damage the engine and cause noise. Knock occurs when end gases autoignite, while surface ignition initiates at hot spots. Various engine variables like temperature, compression ratio, and spark timing can affect knocking.
5.2 combustion and combustion chamber for si enginesFasilMelese
The document discusses combustion and combustion chambers in spark ignition engines. It describes the conditions needed for combustion, the different types of fuel-air mixtures, and the stages of combustion in a homogeneous mixture. The three stages of actual engine combustion are the delay period, flame propagation, and wall quenching. Factors that influence flame speed like turbulence, fuel-air ratio, temperature and pressure are also summarized. Abnormal combustion phenomena of knock and surface ignition are described along with causes of end gas combustion and the effects of various engine variables on knocking.
MODELLING FOR CROSS IGNITION TIME OF A TURBULENT COLD MIXTURE IN A MULTI BURN...ijcsa
This document presents a computational model for determining the cross-ignition time of a turbulent cold mixture in a multi-burner combustor. The model accounts for various parameters that influence heat transfer during the cross-ignition process. Experimental validation was conducted using a simple test rig with two burners. Preliminary results from the experiments show relationships between cross-ignition time and factors like the flow area between burners, distance between burners, and flame properties. Computational fluid dynamics simulations will also be used to further investigate heat transfer in high-velocity regions and validate the model under more conditions.
FINAL Report for Development of Enclosed Combustion Right for SCRAMJET Fuel S...Dan Martin
This document describes the development of an enclosed combustion rig to study ignition of fuels for scramjet engines. The rig uses an opposed jet burner configuration to produce a stable stagnation flame for experimentation. A double helix silicon carbide heating rod is inserted into the top burner to heat the opposing air flow and achieve ignition of fuel-air mixtures passing through the bottom burner. The rig has been tested and can sustain stable stagnation flames. Future work will quantify the effects of heated flow and calibrate the rig to ignite fuels and measure flame properties like ignition temperature, propagation speed, and extinction strain rate. This will provide data on cracked states of jet fuel to inform scramjet combustion design.
Temperature fields during the development of combustion in a rapid compressio...John Clarkson
J. Clarkson, J.F. Griffiths, J.P. MacNamara, & B.J. Whitaker, “Temperature Fields During the Development of Combustion in a Rapid Compression Machine”, Combustion and Flame, 125, 1162-1175, 2001.
Effect of rim geometry on burner stability Conference paper2019Jameel Tawfiq
A swirl burner with different length to rim diameter ratio L/D. A three ratios 1,2 and 3 were studied. The results show that a change in the L/D ratio will effect on the stabilization position of the flame in downstream. The equivalence ratio of the mixture was taken a constant for the comparison sake. The flame stabilizes closer to the rim with an increase of the rim length.
The document discusses combustion in spark-ignition (SI) engines. It defines combustion as a chemical reaction in which fuel combines with oxygen, liberating heat energy. In an SI engine, fuel and air are mixed and inducted into the cylinder where combustion is initiated by a spark at the spark plug near the end of the compression stroke. There are three stages of combustion: ignition lag, flame propagation, and after burning. Abnormal combustion phenomena like pre-ignition and knocking can occur if conditions are not suitable. Factors like turbulence, fuel-air ratio, temperature and pressure, compression ratio, and engine variables affect the flame speed and combustion process.
The document discusses combustion in spark-ignition (SI) engines. It defines combustion as a chemical reaction in which fuel combines with oxygen, liberating heat energy. In an SI engine, fuel and air are mixed and inducted into the cylinder where combustion is initiated by a spark at the spark plug near the end of the compression stroke. The combustion process occurs in three stages: ignition lag, flame propagation, and after burning. Abnormal combustion phenomena like pre-ignition and knocking can occur if conditions are not suitable. Factors like turbulence, fuel-air ratio, temperature and pressure, compression ratio, and engine speed and size can affect the flame speed and combustion characteristics in the engine.
Combustion in a SI engine involves three stages:
1. Flame development stage where the spark ignites the fuel-air mixture and a flame nucleus forms.
2. Flame propagation stage where the flame spreads through the combustion chamber. The flame propagation speed affects combustion efficiency.
3. Flame termination stage where combustion continues after peak pressure is reached if a rich fuel mixture is supplied.
This document discusses combustion in internal combustion engines. It begins by defining combustion as the rapid chemical combination of fuel and oxygen that releases energy in the form of heat. It then describes the different types of combustion that can occur, including complete and incomplete combustion. The document focuses on the combustion processes in spark-ignition (SI) engines and compression-ignition (CI) engines. For SI engines, it describes the typical three stages of combustion: ignition lag, flame propagation, and afterburning. For CI engines, it outlines the four phases of combustion: ignition delay period, uncontrolled combustion, controlled combustion, and afterburning. Key factors that influence combustion in each engine type are also summarized.
This document discusses developments in flame propagation in micro and mesoscale channels. It begins by reviewing recent research on flame propagation parameters like speed, quenching effects, and flame-wall interactions under varied conditions of channel dimensions, flow rates, equivalence ratios, and thermal properties. Specific findings are noted on phenomena like spinning flames and asymmetric/unstable flames. The remainder summarizes experimental and theoretical studies on topics like stretched flames, flame structures, extinction characteristics, and pattern formation under different conditions. The overall focus is on understanding combustion processes at micro/mesoscales through analysis of factors influencing flame stability, propagation, and transitions between modes.
The document discusses combustion in internal combustion engines. It covers:
1) The normal combustion process in spark ignition engines including the 3 stages of combustion and factors affecting flame speed.
2) The combustion process in compression ignition engines including the 4 stages and factors affecting the ignition delay period.
3) Abnormal combustion phenomena like knock and types of abnormal combustion in diesel engines.
Fundamental Aspects of Droplet Combustion ModellingIJERA Editor
This document summarizes research on modeling liquid droplet combustion. It first describes developing a model that solves transient energy and species equations to simulate an isolated, spherically symmetric single-component droplet burning over time. Results show the flame diameter initially increases then decreases and the flame to droplet ratio changes throughout burning unlike quasi-steady models. The model is extended to include forced convection effects. Emission profiles for species like CO, CO2, H2O and NO are also determined. Finally, the document discusses modeling multicomponent droplets, high-pressure combustion, and the governing equations involved.
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.
Numerical Analysis of Inlet Gas-Mixture Flow Rate Effects on Carbon Nanotube ...A Behzadmehr
The growth rate and uniformity of Carbon Nano Tubes (CNTs) based on Chemical Vapor Deposition (CVD)
technique is investigated by using a numerical model. In this reactor, inlet gas mixture, including xylene as
carbon source and mixture of argon and hydrogen as carrier gas enters into a horizontal CVD reactor at
atmospheric pressure. Based on the gas phase and surface reactions, released carbon atoms are grown as CNTs on the iron catalysts at the reactor hot walls. The effect of inlet gas-mixture flow rate, on CNTs growth rate and its uniformity is discussed. In addition the velocity and temperature profile and also species concentrations throughout the reactor are presented.
Similar to International Journal of Computational Engineering Research(IJCER) (20)
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HCL Notes and Domino License Cost Reduction in the World of DLAUpanagenda
Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-and-domino-license-cost-reduction-in-the-world-of-dlau/
The introduction of DLAU and the CCB & CCX licensing model caused quite a stir in the HCL community. As a Notes and Domino customer, you may have faced challenges with unexpected user counts and license costs. You probably have questions on how this new licensing approach works and how to benefit from it. Most importantly, you likely have budget constraints and want to save money where possible. Don’t worry, we can help with all of this!
We’ll show you how to fix common misconfigurations that cause higher-than-expected user counts, and how to identify accounts which you can deactivate to save money. There are also frequent patterns that can cause unnecessary cost, like using a person document instead of a mail-in for shared mailboxes. We’ll provide examples and solutions for those as well. And naturally we’ll explain the new licensing model.
Join HCL Ambassador Marc Thomas in this webinar with a special guest appearance from Franz Walder. It will give you the tools and know-how to stay on top of what is going on with Domino licensing. You will be able lower your cost through an optimized configuration and keep it low going forward.
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DLAU und die Lizenzen nach dem CCB- und CCX-Modell sind für viele in der HCL-Community seit letztem Jahr ein heißes Thema. Als Notes- oder Domino-Kunde haben Sie vielleicht mit unerwartet hohen Benutzerzahlen und Lizenzgebühren zu kämpfen. Sie fragen sich vielleicht, wie diese neue Art der Lizenzierung funktioniert und welchen Nutzen sie Ihnen bringt. Vor allem wollen Sie sicherlich Ihr Budget einhalten und Kosten sparen, wo immer möglich. Das verstehen wir und wir möchten Ihnen dabei helfen!
Wir erklären Ihnen, wie Sie häufige Konfigurationsprobleme lösen können, die dazu führen können, dass mehr Benutzer gezählt werden als nötig, und wie Sie überflüssige oder ungenutzte Konten identifizieren und entfernen können, um Geld zu sparen. Es gibt auch einige Ansätze, die zu unnötigen Ausgaben führen können, z. B. wenn ein Personendokument anstelle eines Mail-Ins für geteilte Mailboxen verwendet wird. Wir zeigen Ihnen solche Fälle und deren Lösungen. Und natürlich erklären wir Ihnen das neue Lizenzmodell.
Nehmen Sie an diesem Webinar teil, bei dem HCL-Ambassador Marc Thomas und Gastredner Franz Walder Ihnen diese neue Welt näherbringen. Es vermittelt Ihnen die Tools und das Know-how, um den Überblick zu bewahren. Sie werden in der Lage sein, Ihre Kosten durch eine optimierte Domino-Konfiguration zu reduzieren und auch in Zukunft gering zu halten.
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HCL Notes und Domino Lizenzkostenreduzierung in der Welt von DLAU
International Journal of Computational Engineering Research(IJCER)
1. International Journal of Computational Engineering Research||Vol, 03||Issue, 7||
www.ijceronline.com ||July ||2013|| Page 33
A Review Of Laminar Burning Velocity Of Gases And Liquid
Fuels.
Vaishali Katre1
, S. K. Bhele2
1, 2
Department of Mechanical Engineering, Kavikulguru Institute of Technology and Science
Ramtek, India
I. INTRODUCTION
The laminar burning velocity is one of the fundamental properties of a reacting premixed mixture and
its reliable data are constantly needed for combustion applications. So far, several techniques for measuring the
one-dimensional laminar burning velocity have been used, and for a wide range of temperature, pressure, and
fuel rather accurate measurements have been obtained by employing flat or curved flames in stagnation flow,
propagating spherical flames in combustion vessel or flat flames stabilized on burner. With all those
measurement technique proper care could be taken to remove the effect of flame stretch either during
experimentation or through further data processing.
1.1 Importance of laminar burning velocity
Laminar burning velocity is an important parameter of a combustible mixture as it contains
fundamental information regarding reactivity, diffusivity, and exothermicity. Its accurate knowledge is essential
for engine design, modeling of turbulent combustion, and validation of chemical kinetic mechanisms. In
addition, the determination of burning velocity is very important for the calculations used in explosion
protection and fuel tank venting. Burning velocity is defined as the linear velocity of the flame front normal to
itself relative to unburned gas, or as the volume of unburned gas consumed per unit time divided by the area of
the flame front in which that volume is consumed. Laminar burning velocity is highly useful for modeling
turbulent burning velocity. Turbulent flow occurs when a fluid undergoes irregular fluctuations and mixing.
Laminar flow is defined as the flow which travels smoothly in regular paths or layers.
1.2 Flame front propagation
For efficient combustion the rate of propagation of the flame front within the cylinder is quite critical.
The two important factors which determine the rate of movement of the flame front across the combustion
chamber are the reaction rate and the transposition rate. The reaction rate is the result of a purely chemical
combination process in which the flame eats its way into the unburned charge. The transposition rate is due to
the physical movement of the flame front relative to the cylinder wall and is also the result of the pressure
differential between the burning gases and the unburnt gases in the combustion chamber.
ABSTRACT:
The laminar burning velocity is a fundamental property of a fuel that affects many aspects of
its combustion behaviour. Experimental values are required to validate kinetic simulations, and also to
provide input for models of flashback, minimum ignition energy and turbulent combustion. The laminar
burning velocity is one of the most essential parameters for analysis and performance predictions of
various combustion engines. It is the velocity, relative to the unburned gas, with which a plane, one-
dimensional flame front travels along the normal to its surface. The majority of turbulent combustion
models require knowledge of laminar burning velocity of the fuel-air mixture as a function of the
mixture strength. Also reliable experimental data are needed in order to test and calibrate thermo-
kinetic combustion models which have been quite successful for combustion predictions of simple
hydrocarbon fuels. There are different methods to determine the burning velocity such as Heat flux
burner method, Flat flame burner method, Bunsen burner method, Slot burner technique, Counter flow
diffusion flow, Soap bubble technique, and Tube propagating method.
KEYWORDS: Burning velocity, Bunsen burner, Flame front, Flame speed.
2. A Review Of Laminar Burning Velocity…
www.ijceronline.com ||July ||2013|| Page 34
Area III
Area II
Area I
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80
60
40
20
0
0 20 40 60 80 100
D
C
B
A
Distanceofflametravelacrossthechamber(%)
Time of flame travel across the chamber (%)
Figure 1: Details of flame travel
Figure shows the rate of flame propagation. In area 1, (A→B), the flame front progresses relatively
slowly due to a low transposition rate and low turbulence. The transposition of the flame front is very little since
there is a comparatively small mass of charge burned at the start. The low reaction rate plays a dominant role
resulting in a slow advance of the flame. Also, since the spark plug is to be necessarily located in a quiescent
layer of gas that is close to the cylinder wall, the lack of turbulence reduces the reaction rate and hence the fame
speed. As the flame front leaves the quiescent zone and proceeds into more turbulence areas (area2) where it
consumes a greater mass of mixture, it progresses more rapidly and at a constant rate (B→C) as shown in figure.
The volume of unburned charge is very much less towards the end of flame travel and so the transposition rate
again becomes negligible thereby reducing the flame speed. The reaction rate is also reduced again since the
flame is entering a zone area (area 3) of relatively low turbulence (C→D) in figure.
1.3 Factor influencing the flame speed
The study of factors which affect the velocity of flame propagation is important since the flame
velocity influences the rate of pressure rise in the cylinder and it is related to certain types of abnormal
combustion that occur in spark-ignition engines. There are several factors which affect the flame speed, to a
varying degree, the most important being the turbulence and the fuel-air ratio. Details of various factors that
affect the flame speed are discussed below.
1.3.1 Turbulence
The flame speed is quite low in non-turbulent mixtures and increases with increasing turbulence. This
is mainly due to the additional physical intermingling of the burning and unburned particles at the flame front
which expedites reaction by increasing the rate of contact. The turbulence in the incoming mixture is generated
during the admission of fuel- air mixture through comparatively narrow sections of the intake pipe, valve
openings etc., in the suction stroke. Turbulence which is supposed to consist of many minute swirls appears to
increase the rate of reaction and produce a higher flame speed than that made up of larger and fewer swirls. A
suitable design of the combustion chamber which involves the geometry of cylinder head and piston crown
increases the turbulence during the compression stroke.
1.3.2 Fuel-air ratio
The fuel air ratio has a very significant influence on the flame speed. The highest flame velocities are
obtained with somewhat richer mixture. When the mixture is made leaner or richer the flame speed decreases.
Less thermal energy is released in the case of lean mixtures resulting in lower flame temperature. Very rich
mixtures lead to incomplete combustion which results again in the release of less thermal energy. 1.3.3
Temperature and pressure Flame speed increases with an increase in intake temperature and pressure. Higher
initial pressure and temperature may help to form a better homogeneous air-vapour mixture which helps in
increasing the flame speed. This is possible because of an overall increase in the density of the charge.
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1.3.4 Compression ratio
A higher compression ratio increases the pressure and temperature of the working mixture which
reduce the initial preparation phase of combustion and hence less ignition advance is needed. High pressures and
temperatures of the compressed mixture also speed up the second phase of combustion. Increase compression
ratio reduces the clearance volume and therefore increases the density of the cylinder gases during burning. This
increases the peak pressure and temperature and total combustion duration is reduced. Thus engines having
higher compression ratios have higher flame speeds. According to S.Y. Liao et al carried out the study on
Determination of the laminar burning velocities for mixtures of ethanol and air at elevated temperatures. It has
measured the laminar burning velocities for ethanol-air premixed flames at various temperature and equivalence
ratio. The flames are analyzed to estimate flame size, consequently, the flame speeds are derived from the
variations of the flame size against the time elapsed. It was studied the effects of the fuel/air equivalence ratio,
initial temperature and pressure on the laminar flame propagation. It was conducted the premixed laminar
combustion of ethanol-air mixture experimentally in a closed combustion bomb. And it was found the laminar
burning velocity 58.3 cm/s at normal pressure of 0.1 MPa and temperature of 358 K.Xuan Zhang et al carried
out the study on Measurements of laminar burning velocities and flame stability analysis for dissociated
methanol–air–diluents mixtures at elevated temperatures and pressures. In this the laminar burning velocities
and Markstein lengths for the dissociated methanol–air–diluent mixtures were measured at different equivalence
ratios, initial temperatures and pressures. The influences of these parameters on the laminar burning velocity and
Markstein length were analyzed. It was found that the peak laminar burning velocity occurs at equivalence ratio
of 1.8. The Markstein length decreases with an increase in initial temperature and initial pressure. Measurements
of laminar burning velocities and flame Stability analyses are conducted using the outwardly spherical laminar
premixed flame for DM–air and DM–air–diluents mixtures. The laminar burning velocity and Markstein length
at different equivalence ratios, initial temperatures, initial Pressures and N2/CO2 dilution ratios are
obtained.Erjiang Hu et al carried out the numerical study on laminar burning velocity and NO formation of the
premixed methane–hydrogen–air flames.
It was found that the unstretched laminar burning velocity is increased with the increase of equivalence ratio and
it decreases as the mixtures become fuel-rich.
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Peak value of unstretched laminar burning velocity of methane–air mixture is presented at the
equivalence ratio of 1.1 and that of hydrogen–air mixture is presented at equivalence ratio of 1.8.Methane-
dominated combustion is presented when hydrogen fraction is less than 40%, where laminar burning velocity is
slightly increased with the increase of hydrogen addition. When hydrogen fraction is larger than 40%, laminar
burning velocity is exponentially increased with the increase of hydrogen fraction. With the increase of
hydrogen fraction, the overall activation energy of methane–hydrogen mixture is decreased, and the inner layer
temperature and Zeldovich number are also decreased. All these factors contribute to the enhancement of
combustion as hydrogen is added.
S. Jerzembeck et al carried out the research on Spherical flames of n-heptane, iso-octane, PRF 87 and
gasoline/air mixtures. These are experimentally investigated to determine laminar burning velocities and
Markstein lengths under engine-relevant conditions by using the constant volume bomb method. Data are
obtained for an initial temperature of 373 K, equivalence ratios varying from = 0.7 to = 1.2, and initial
pressures from 10 to 25 bar. To track the flame front in the vessel a dark field He–Ne laser Schlieren
measurement technique and digital image processing were used. The laminar burning velocities are obtained
through a linear extrapolation to zero stretch. The experimentally determined Markstein numbers are compared
to theoretical predictions. A reduced chemical kinetic mechanism for n-heptane and iso-octane was derived from
the Lawrence Livermore comprehensive mechanisms.S.P. Marshall et al are done research on the laminar
burning velocity measurements of liquid fuels at elevated pressures and temperatures with combustion residuals.
It was found that the laminar burning velocity is a fundamental property of a fuel that affects many aspects of its
combustion behavior. Experimental values are required to validate kinetic simulations, and also to provide input
for models of flashback, minimum ignition energy and turbulent combustion. A constant volume vessel (rated at
3.4 MPa) in conjunction with a multi-zone model was used to calculate burning velocity from pressure and
schlieren data, allowing the user to select data uncorrupted by heat transfer or cellularity. n-Heptane, iso-octane,
toluene, ethylbenzene and ethanol were tested over a wide range of initial pressures (50, 100, 200 and 400 kPa),
temperatures (310, 380 and 450 K) and equivalence ratios (0.7–1.4), along with tests using combustion residuals
at mole fractions of up to 0.3.
Shuang-Feng Wanga et al carried out the study on Laminar burning velocities and Markstein lengths of
premixed methane/air flames near the lean flammability limit in microgravity. In this literature the researchers
studied the effects of flame stretch on the laminar burning velocities of near-limit fuel-lean methane/air flames
have been studied experimentally using a microgravity environment to minimize the complications of buoyancy.
Outwardly propagating spherical flames were employed to assess the sensitivities of the laminar burning
velocity to flame stretch, represented by Markstein lengths, and the fundamental laminar burning velocities of
unstretched flames. Resulting data were reported for methane/air mixtures at ambient temperature and pressure,
over the specific range of equivalence ratio that extended from 0.512 (the microgravity flammability limit found
in the combustion chamber) to 0.601. Furthermore, the burning velocities predicted by three chemical reaction
mechanisms. Additional results of the present investigation were derived for the overall activation energy and
corresponding Zeldovich numbers, and the variation of the global flame Lewis numbers with equivalence ratio.
The implications of these results were discussed.
II. DISCUSSION
Various literatures on evaluating the laminar burning velocity has been reviewed briefly and it is
noticed that laminar burning velocities for hydrocarbon-air mixture are about 0.4 m/s and under turbulent flow
conditions are unlikely to be much above 1.5 m/s. The Bunsen burner will accept flow velocities up to five times
the burning velocity so that the maximum flow velocity which can be considered with this design of burner must
be about 2 m/s. With rising oil prices and global warming being a dominant environmental issue, it seems that
the use of alternative fuels in future is inevitable. These leading goals for both energy security and clean air
project have resulted in heightened interests in the worldwide utilizations of alternative fuels in burners and
engines. One of the most important parameters for any fuel is the laminar burning velocity. This property forms
an important input parameter for models of turbulentCombustion and ignition limits. It is also important in
engine simulations, which directly affects power output and efficiency. The experimental procedure used in this
work follows closely that of Bradley et al, Metghalchi and Keck, Law et al, and Gülder, these groups also
investigated spherical expanding flames at high pressures to determine laminar burning velocities of premixed
mixtures in a preheated closed vessel with optical access. In these works, data measured over a similar range of
stretch rates were extrapolated to zero stretch value following the approach. Lewis, streholow, Vagelopolous
among others has found that the relationship between equivalence ratio and burning velocity is in the form of a
bell curve approximately care necessary. The first step is entered on Ø=1. In order to calculate the equivalency
ratio . For this experiment a series of calculations are necessary.
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= (fuel/air) actual / (fuel/air)stoic
A significant characteristic that affects burning velocity is the degree of turbulence in the flame.
Ideally, the flame being measured should be laminar. A laminar flame has parallel flow lines, and therefore
results in a uniform, steady flame. The Reynolds number (Re) is used to determine the state of the flow for a
given apparatus. The equation for the Reynolds number is
Re = ρνd/µ
Most importantly, for Re<2300 the flow is laminar, and for Re > 3200 it is typically turbulent. A laminar flame
is precise and sharply defined which is necessary to accurately determine burning velocity. ρ is density of
mixture, ν is the average velocity, d is diameter of burner tube, µ is dynamic viscosity.
The flame speed is determined by,
Sb= drb/ dt
Where, Sb is the flame speed with respect to the burned gas and rb is the flame front displacement.
Therefore, values of the Schlieren radius rsch determined by image tracking of Schlieren cinematography are
close to rb. Flame images were analyzed with an image processing code specifically developed for the
experimental configuration to track flame front radii over time. The burned propagating flame speed Sb was
determined from first-order least squares fits through four radii adjacent to each point under consideration.
Contrast levels were set to define consistently flame fronts at all times.
The unburned unstretched flame speed (Su) was obtained from continuity,
Sb ρb = Su ρu
The values ρb and ρu are the burned and unburned densities of the mixture and were computed with the
one dimensional flame code Flame Master.
III. FUTURE SCOPE
The experimental setup for this project had several flaws that are significant sources for the margin of
error in the data.Particular focus should be on a redesign of the apparatus Possible improvements should include
a section of greater vertical distance prior to the slot itself to attempt to induce a flow that is more laminar, and
generally less twists and turns in the tubing and adapters. For the Bunsen burner apparatus the most significant
improvement would be to add a second tube to the apparatus. The tube would surround the existing burner tube,
and it would provide a flow of an inert gas, such as nitrogen. This flow would stop the leakage that occurs in a
horizontal direction under atmospheric conditions. This is ideal to provide an exact cone shaped flame, which
will in turn provide a more accurate measurement for surface area and finally burning velocity. Burning velocity
is depends on the size of the burner tube, a detailed analysis of the effect of tube diameter on burning velocity
measurements is part of a future study related to this work.
IV. CONCLUSION
The laminar burning velocity is one of the fundamental properties of a reacting premixed mixture and
its reliable data are constantly needed for combustion applications. So far, several techniques for measuring the
laminar burning velocity have been used, and for a wide range of temperature, pressure, and fuel rather accurate
measurements have been obtained by employing flat or curved flames in stagnation flow propagating spherical
flames in combustion vessel or flat flames stabilized on burner. With all those measurement techniques proper
care could be taken to remove the effect of flame stretch either during experimentation or through further data
processing. Measurements were based on motion picture schlieren photographs of outwardly propagating
spherical flames. A heated spherical combustion vessel has been used with systems for fuel injection, ignition,
experiment control, data acquisition and high speed schlieren photography. This study focuses on the effects of
initial temperature and fuel/air equivalence ratio on the laminar burning velocities of gases and liquids.
REFERENCES
Journal Papers:
[1] S.Y. Liao, D.M. Jiang, Z.H. Huang, K. Zeng, Q. Cheng, “Determination of the laminar burning velocities for mixtures of
ethanol and air at elevated temperatures”,Applied Thermal Engineering,vol.27, pp 374-380,2007.
[2] Xuan Zhang, Zuohua Huang, Zhiyuan Zhang, Jianjun Zheng, Wu Yu, Deming Jiang, “Measurements of laminar burning
velocities and flame stability analysis for dissociated methanol–air–diluents mixtures at elevated temperatures and
pressures”, International journal of Hydrogen Energy vol.34, pp 4862-4875,2009.
[3] Erjiang Hu, Zuohua Huang, Jianjun Zheng, Qianqian Li, Jiajia He, “ Numerical study on laminar burning velocity and
NO formation of premixedmethane–hydrogen–airflames”, International journal of Hydrogen Energy, vol. 34, pp 6545-
6557,2009.
6. A Review Of Laminar Burning Velocity…
www.ijceronline.com ||July ||2013|| Page 38
[4] S. Jerzembeck , N. Peters, P. Pepiot-Desjardins , H. Pitsch, “Laminar burning velocities at high pressure for primary
reference fuels and gasoline: Experimental and numerical investigation”, Combustion and Flame, vol. 156, pp 292-
301,2009.
[5] S.P. Marshall , S. Taylor , C.R. Stone, T.J. Davies , R.F. Cracknell, “Laminar burning velocity measurements of liquid
fuels at elevated pressures and temperatures with combustion residuals”, Combustion and Flame vol. 158, pp 1920-
1932,2011.
[6] Shuang-Feng Wanga,, Hai Zhang b, Jozef Jarosinski c, Andrzej Gorczakowski c, Jerzy Podfilipski, “Laminar burning
velocities and Markstein lengths of premixed methane/air flames near the lean flammability limit in microgravity”,
Combustion and Flame vol 157, pp 667-675,2010.
[7] Ganeshan v.,„„internal combustion engine ” third edition Published By the Tata McGraw-Hill Publishing Company
Limited, 7 West Patel Nagar, New Delhi 110008. pp 372-375.
[8] Esam M. Mohamed, “Burning velocities & flam temperatures of ethanol & butanol-air mixtures”. Technical Institute /
Babylon 2010.
AUTHOR’S PROFILE
V. J. Katre is a student of final semester of P.G course in Engineering (Heat Power Engineering) of
KITS at Ramtek, Nagpur University, India.
S. K. Bhele is an Associate Professor at KITS, Ramtek in the Mechanical Engineering Department. He
has 15 years teaching experience. He has published 03 technical papers in International Conference and
05 technical papers in National conferences and is a Life Member of ISTE, SAE, and Associate
Member of Institute Engineers. Pursuing PhD from VNIT Nagpur, India.