The basic mixing phenomena in confined, coaxial, particle-laden turbulent flows are studied withi... more The basic mixing phenomena in confined, coaxial, particle-laden turbulent flows are studied within the scope of ram combustor research activities. Cold-flow experiments in a relatively simple configuration of confined, coaxial two-phase jets provided both qualitative and quantitative insight on the multiphase mixing process. Pressure, tracer gas concentration, and two-phase velocity measurements revealed that unacceptably long ram combustors are needed for complete confined jet mixing. Comparison of the experimental results with a previous numerical simulation displayed a very good agreement, indicating the potential of the experimental facility for validation of computational parametric studies.
Volume 2: Combustion, Fuels and Emissions, Parts A and B, 2012
This study investigates the performance and the conditions under which flameless oxidation can be... more This study investigates the performance and the conditions under which flameless oxidation can be achieved for a given annular adiabatic combustor. Numerical modelling of velocity, temperature and species fields are performed for different flow configurations of air and methane streams injected into a proposed design of a gas-turbine combustor. Parametric analysis was performed by systematically varying several parameters: radius of a recirculation zone, radius of the combustor, location of air and fuel ports, air and fuel velocities magnitudes and injection angles. The analysis was performed initially using a three-step global chemistry model to identify a design (geometry and operating conditions) that yield flameless combustion regime. The selected design was then modelled using a skeletal (46 reactions) and a detailed (309 reactions) chemical kinetics mechanism. The k–ε turbulence model was used in the most calculations. Overall, similar qualitative flow, temperature, and specie...
We introduce a method for measuring the speed of sound dispersion. It combines a short pulse tran... more We introduce a method for measuring the speed of sound dispersion. It combines a short pulse transmission followed by a long burst comprised of two frequencies, one being double that of the other. The method allows the determination of the speed of sound dispersion using a single transmission. To validate the method, the dispersion was first measured in plastic samples
The basic mixing phenomena in confined, coaxial, particle-laden turbulent flows are studied withi... more The basic mixing phenomena in confined, coaxial, particle-laden turbulent flows are studied within the scope of ram combustor research activities. Cold-flow experiments in a relatively simple configuration of confined, coaxial two-phase jets provided both qualitative and quantitative insight on the multiphase mixing process. Pressure, tracer gas concentration, and two-phase velocity measurements revealed that unacceptably long ram combustors are needed for complete confined jet mixing. Comparison of the experimental results with a previous numerical simulation displayed a very good agreement, indicating the potential of the experimental facility for validation of computational parametric studies.
Volume 2: Combustion, Fuels and Emissions, Parts A and B, 2012
This study investigates the performance and the conditions under which flameless oxidation can be... more This study investigates the performance and the conditions under which flameless oxidation can be achieved for a given annular adiabatic combustor. Numerical modelling of velocity, temperature and species fields are performed for different flow configurations of air and methane streams injected into a proposed design of a gas-turbine combustor. Parametric analysis was performed by systematically varying several parameters: radius of a recirculation zone, radius of the combustor, location of air and fuel ports, air and fuel velocities magnitudes and injection angles. The analysis was performed initially using a three-step global chemistry model to identify a design (geometry and operating conditions) that yield flameless combustion regime. The selected design was then modelled using a skeletal (46 reactions) and a detailed (309 reactions) chemical kinetics mechanism. The k–ε turbulence model was used in the most calculations. Overall, similar qualitative flow, temperature, and specie...
We introduce a method for measuring the speed of sound dispersion. It combines a short pulse tran... more We introduce a method for measuring the speed of sound dispersion. It combines a short pulse transmission followed by a long burst comprised of two frequencies, one being double that of the other. The method allows the determination of the speed of sound dispersion using a single transmission. To validate the method, the dispersion was first measured in plastic samples
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