Linear Stability of Stratified Flow of Two Viscous Fluids

Abstract

Stability to small perturbations of two-layered parabolic flow in a plane channel is analyzed. The dispersion relation between a disturbance wavelength and its growth rate is valid in the whole range of wavenumbers and for moderately large Reynolds numbers. The results coincide with known asymptotic theory conclusions. Besides, a new effect for flows not only with viscosity stratification but also with density stratification is revealed. The agreement with experimental data is acceptable.