Response of a two-layer compliant slab to inviscid incompressible fluid flow

Abstract

In this study, the dynamics of two-dimensional wave trains at the interface between a two-layer viscoelastic coating and flow of an inviscid fluid is examined theoretically. The objective is to understand the interaction mechanism between the two media better, and to explore the effects of different geometric and material properties on this mechanism. Each layer of coating is treated as an infinite, elastic, or viscoelastic solid of finite thickness, bonded to each other. The flow is modeled by the potential theory. The two media, two-layer slab and the fluid, are coupled through stress and velocity, normal to the surface of the slab. Two layers of the slab are assumed to be bonded to each other. The proposed mathematical model is used to predict the appearance of unstable surface waves of the coating. A few dimensionless parameters are identified. The model predicts that the instabilities initiate in the form of standing waves for the viscoelastic coating while the speed of the unstable waves at the interface of the elastic coating and the fluid is relatively high.