Direct Numerical Simulation of Reacting Mixing Layers. Effect of Heat Release and Density Difference of Mean Flow.

Abstract

The objective of this paper is to clarify the effect of heat release and density difference in mean flow on the development of mixing layers. To achieve this purpose, we have performed a direct numerical simulation of a two-dimensional chemically reacting mixing layer by means of a spectral method. Low Mach number approximation was used to take into account the effect of density change. From these results, we have obtained the following conclusions. (1) Heat release causes baloclinic torque in the outside region of the coherent structure. Because of this baloclinic torque, the growth of the mixing layer and chemical reaction are suppressed. (2) The density difference of mean flow suppresses the growth of the mixing layer and chemical reaction because of the baloclinic torque and expansion. (3) The growth of the mixing layer and chemical reaction are further suppressed by the coexistence of heat release and density difference.