A Calculation Method of Three-Dimensional Supercavity Shape Based on the Principle of Independent Expansion

In view of the problem that the fluid dynamics calculation of supercavity torpedo maneuvering needs to accurately predict the three-dimensional supercavity shape in real time, a three-dimensional unsteady supercavity shape calculation method is presented based on the independent expansion principle of cavity section. The reasonability of the method is testified by comparing with the Logvinovich model and the computational fluid dynamics(CFD) numerical simulation method. The three-dimensional supercavity shapes of a torpedo in velocity-variable motion, depth-variable motion, horizontal-longitudinal plane motion along sinusoidal trajectory, and spiral motion in three-dimensional space are simulated and analyzed by the proposed method. Simulation results show that this method can predict three-dimensional unsteady supercavity shape of a torpedo moving along any trajectory. Compared with the Logvinovich model and the CFD numerical simulation method, this method can solve the three-dimensional supercavity shape with more comprehensive information and can save a large amount of computing resource. It is concluded that the present method can rapidly provide time-varying three-dimensional supercavity shape for engineering practice and provide a reference for the establishment of dynamic model of supercavity torpedo.