二次元/三次元反応性自由せん断流の数値シミュレーション

抄録

The evolution of two- and three-dimensional vortical structures in an initially nonpremixed temporally developing reacting mixing layer is simulated by solving the time-dependent, compressible Navier-Stokes equations. The result of the numerical simulations shows that, as the evolution of hydrodynamic instability is suppressed, and the vorticity and the amount of chemical product are reduced by the baroclinic effect and volumetric expansion due to reaction heat release. In the case of temperature dependent diffusivities, the vorticity is reduced as well, in comparison with the temperature-independent case. Structures of the cores, ribs and legs are observed in the three dimensional mixing layer. Similarities between the distributions of spanwise vorticity and product mass fraction, and between those of streamwise vorticity and reaction rate, can be identified when the pairing process is saturated which may imply that the streamwise vortical dynamics plays an essential role in the progress of the chemical reaction.