Modeling of turbulent supersonic H2air combustion with a multivariate beta PDF
Abstract
Recent calculations of turbulent supersonic reacting shear flows using an assumed multivariate beta PDF (probability density function) resulted in reduced production rates and a delay in the onset of combustion. This result is not consistent with available measurements. The present research explores two possible reasons for this behavior: use of PDF's that do not yield Favre averaged quantities, and the gradient diffusion assumption. A new multivariate beta PDF involving species densities is introduced which makes it possible to compute Favre averaged mass fractions. However, using this PDF did not improve comparisons with experiment. A countergradient diffusion model is then introduced. Preliminary calculations suggest this to be the cause of the discrepancy.
 Publication:

Joint Propulsion Conference and Exhibit
 Pub Date:
 June 1993
 Bibcode:
 1993jpmc.confRW...B
 Keywords:

 Hydrogen Fuels;
 Multivariate Statistical Analysis;
 Probability Density Functions;
 Reacting Flow;
 Supersonic Combustion;
 Turbulence Models;
 Turbulent Combustion;
 Hypersonic Flight;
 Shear Flow;
 Turbulent Diffusion;
 Fluid Mechanics and Heat Transfer