Research on the influence of ocean currents on underwater launching of vehicles

Ocean currents are a key factor influencing the attitude changes of vehicles during underwater launches, directly affecting the stability of the water-exit trajectory and the likelihood of a successful launch. This study employs a three-dimensional numerical simulation method to capture the characteristics of cavity evolution during underwater launch and systematically investigate the interaction between ocean currents, cavities, and vehicle motion. The results demonstrate that ocean currents significantly impact the symmetry of the shoulder cavity, the jet angle following the collapse of the tail cavity. These changes alter the vehicle's angular velocity and deflection angle, resulting in a curved trajectory. This trajectory curvature induces a non-vertical water exit, triggering asymmetric collapse of the shoulder cavity and high-magnitude collapse loads. When the current velocity is 0 or 0.5 m/s, the effect on the vehicle's water-exit behavior is negligible. However, at velocities of 1.0 and 1.5 m/s, the vehicle experiences significant tilt upon exiting the water, increasing the localized load on the vehicle surface and negatively impacting the launch process.