IMPACT OF 2 BODIES ONE OF WHICH IS COVERED BY A THIN-LAYER OF LIQUID

The paper deals with the plane unsteady problem of the collision of tw o rigid undeformable and shallow surfaces, one of which is covered by a thin layer of an ideal incompressible liquid. At the initial instant of time; a dry surface touches the liquid free boundary at a single p oint and then starts to penetrate the liquid layer. The flow region is divided into four parts : the region beneath the entering surface, th e jet root, the spray jet and outer region. Inside each of those subdo mains the flow patterns have their own peculiarities and are analysed separately. The matching conditions allow us to obtain the uniformly v alid asymptotic solution of the original problem. The relative body mo tion and the characteristics of the spray jets generated under the imp act are se determined. The condition on the shapes of the bodies, unde r which the velocity of the impact of the rigid surfaces is non-zero, is derived.