SIMPLIFIED FRAMEWORK FOR DESCRIPTION OF MIXING WITH CHEMICAL REACTIONS(Ⅰ)PHYSICAL PICTURE OF MICRO-AND MACROMIXING

摘要

1 INTRODUCTION When a fluid is injected into a turbulence field to mix with another fluid,twohomogenization processes take place simultaneously:micromixing(on the molecularscale)and macromixing(on the mixer scale).For micromixing,three successive stages arerecognized at high Schmidt number(1)turbulent dispersion,in which the original ma-terial lumps are dispersed by turbulence into discrete elements with smallest eddy sizeλ_k;(2)viscous deformation,in which the size of the elements is further