On the long-range action of turbulent pressure fluctuations

Experimental studies of turbulent flow have shown that turbulent fluctuations generated in a flow, in addition to being carried downstream (convection transfer) are transported normal to the stream lines. The latter effect, occurring not only at adjacent layers (diffusion) but also over large distances, is termed long-range action of turbulence. The theory of long-range action of turbulent pressure fluctuations, developed in the present paper, is shown to yield the distribution of turbulent parameters over the cross section of jets and boundary layers. It also describes the increase in turbulence of a constant velocity flow and a jet flame front, and is capable of explaining the existence of velocity fluctuations in wall boundary layers and laminar sublayers.