Stability of liquid films adjacent to compressible streams

An analysis is presented for the linear stability of a liquid film, adjacent to a compressible viscous gas stream. The analysis is valid for all wavelengths and liquid Reynolds numbers. The pressure and shear perturbations exerted by the gas on the liquid are calculated, using a gas model which takes into account the gas viscosity, velocity profile, and heat transfer. The results show that an inviscid, uniform stream model for the gas is inadequate unless the disturbed boundary layer is very thin. Although the present linear analysis is in fairly good agreement with the experimental observations for subsonic flow, it does not predict the observed wavelengths and wave speeds for supersonic flow.