"Parameter equivalent decomposition" of hydrodynamic forces when supercavitating vehicle oscillating

Considering spatial motion in both horizontal and vertical planes, a new stable motion pattern of "conic-like" oscillation exists in high-speed supercavitating vehicles (HSSVs), posing new challenges to underwater stable navigation technology. To fully understand the motion and force characteristics of the "conic-like" oscillation, numerical simulation methods and experiments were conducted. The "parameter equivalent decomposition" method for the oscillating force of HSSVs is proposed depending on the cavity-vehicle relationship and hydrodynamic equilibrium formulae, and the complex force environment of the "conic-like" oscillation process is decomposed into position and damping components that are easy to analyze. Finally, the position and damping coefficients obtained by the proposed method are integrated into the kinetic model. Comparing the oscillating trajectories achieved by numerical simulation, kinetic model, and experimental methods, the precision of the numerical simulation method and the effectiveness of the "parameter equivalent decomposition" method are validated.