PROBABILITY DENSITY-FUNCTION APPROACH FOR COMPRESSIBLE TURBULENT REACTING FLOWS

The objective of the present work is to extend the probability density function (PDF) turbulence model to compressible reacting flows. The p robability density function of the species mass fractions and enthalpy are obtained by solving a PDF evolution equation using a Monte Carlo scheme. The PDF solution procedure is coupled with a compressible fini te-volume flow solver which provides the velocity and pressure fields. A modeled PDF equation for compressible flows, capable of treating fl ows with shock waves and suitable to the present coupling scheme, is p roposed and tested. Convergence of the combined finite-volume Monte Ca rlo solution procedure is discussed. Two supersonic diffusion flames a re studied using the proposed PDF model and the results are compared w ith experimental data; marked improvements over solutions without PDF are observed.