On the growth, limiting thickness and dominant eddy scale of turbulent shearing layers in the atmosphere

Abstract

The growth of an unbounded, density-stratified, turbulent shearing layer in the presence of a gravity field is studied using the postulate of marginal instability. It is found, for a similarity mean velocity and density distribution, that after a rapid initial growth rate the growth slows asymptotically to zero as the Richardson number approaches a value of 1/4. Furthermore, the theory predicts a constant dominant turbulent eddy scale in all but the initial stages of growth of the turbulent shearing layer.Both the general growth characteristics and the constant dominant turbulent eddy scale predicted by the theory are confirmed by experimental data.