Supercavitating Propellers History, Operating Characteristics, Mechanism of Operation

摘要

This paper contains discussions of: The historical development of supercavitating and ventilated propellers; their operating characteristics; and the mechanism of their operation. The operating characteristics are discussed largely in terms of four regimes of propeller operation for which definitions are given. These are: subcavitating, partially cavitating, supercavitating, and fully-supercavitating. The presentation of propeller characteristics in various forms and their meaning is discussed. The arched shape of the fully-supercavitating characteristic curve (k sub t vs. J) is described and explained. New phenomena which dominate the mechanism of operation of supercavitating propellers are described. These are cavity blockage and blade-cavity interference. Some quantitative theoretical results relating to these phenomena are presented. It is explained how these phenomena account for effects on thrust and efficiency, observed experimentally, but not previously understood. Fundamental differences in the mechanism of operation of sub and supercavitating propellers are revealed. (Author)