Some Results Concerned with Cavitation Studies in Unsteady Hydrodynamics Laboratory of Moscow State University

Abstract

The results of theoretical and experimental cavitation studies obtained in the unsteady hydrodynamics Laboratory of MSU (founded on academitian Sedov's initiative in 1960) are given. The theoretical and experimental results presented are based on the dimension and similitude theory. A number of self-similar solutions describing unsteady jet flows (including a new solution involving a llength parameter) are outlined. The new solution describes, e.g., the high velocity inertial body motion in fluid. The important feature of this self-similar solution is that the cavity form is concerved during the process of body deceleration. Other self-similar solutions describe different stages of fluid - blunt body impact, in particular, when the atmosphere influence on the jet formation is taken into account. An experimental method to measure nondimensional equation of state for water (using a medium which includes small gas bubbles) is suggested. The influence of gas washing down (in the form of a bubble wake) on the drag and thrust is also considered. For high velocity flows it is shown that one can regulate the pressure distributions on a cavity surface. The experimental facilities which make it possible to model practically all parameters of cavitation flows are described. More information on the subject one can find in author's review papers Yakimov (1982), (1991), (1992).