Effects of Turbulence on the Mixing and Chemical Reaction for Cross Flow and Coflowing jets

Abstract

The subject of reactive mixing in turbulent flows is one of vast technological importance and arises in many practical situations such as combustion devices, batch, tubular and continuous stirred tank reactors, chemical lasers and photochemical reactions in the atmospheric boundary layer. Turbulence is known to influence strongly the diffusion process and as a result the chemical reaction in a flowing fluid mixture. If the time scale characterizing the reaction kinetics is much greater than any appropriate time scale of turbulent scalar transport in the flow, then the chemical reaction is said to be slow. In this case turbulence succeeds in mixing the constituents before any chemical reactions become effective. In the opposite case the reaction proceeds at a rate determined by the fluid transport process through turbulent and molecular diffusion.