A NEW METHOD FOR THE ANALYSIS OF UNSTEADY PROPELLER CAVITATION AND HULL SURFACE PRESSURES

Abstract

The method presented in this paper is intended to become a practical tool for the propeller designer, capable of limiting the need for costly and time-consuming experimental tests. A discrete gridwork of elementary vortices and sources forms the basis of a theoretical model of the propeller blade. The free vortex surfaces behind the blades include the so-called variable zone, which reflects the history of the unsteady operation of the propeller and which provides the feedback between this history and the current kinematic situation on the blades. The method is developed into an efficient computer program of moderate size and relatively short execution time. The results of an extensive experimental verification of the program are presented and analyzed. This verification shows that the quality of the results produced by the program is fully comparable with those obtained from the experimental testing of the propeller models.