ACOUSTIC-WAVES IN UNBOUNDED SHEAR FLOWS

The linear evolution of acoustic waves in a fluid flow with uniform me an density and uniform shear of velocity is investigated. The process of the mean flow energy extraction by the three-dimensional acoustic w aves, stimulated by the non-normal character of the linear dynamics in the shear flow, is analyzed. The thorough examination of the dynamics of different physical variables characterizing the wave evolution is presented. The physics of gaining of the shear energy by acoustic wave s is described. (C) 1997 American Institute of Physics.