The propagation of a passive admixture from a local instantaneous source in a turbulent mixing zone

Abstract

The propagation of a passive admixture from a local instantaneous source in a turbulent mixing zone in a stable stratified fluid (two-dimensional problem) is simulated numerically. The location of the source does not coincide with the center of the turbulent zone. The calculation results indicate that the average admixture concentration distribution depends significantly on the initial data. The location of the maximum concentration in homogeneous and linearly stratified fluid is fairly slowly displaced toward the center of the zone. Calculations in a pycnocline show that situations are possible when the propagation of a passive admixture is largely determined by a convective flow generated by the turbulent mixing zone.