Overview of High-Speed Supercavitating Vehicle Control

Even in its simplest conceptualization, supercavitating vehicle dynamics features slope- discontinuous force curves and time-delay effects. To complicate matters, supercavitating vehicles traverse a complicated state during transition from fully-wetted to supercavitating operation. During this phase of flight, when the vaporous cavitation number is relatively high, rapid ventilation can lead to cavity auto-oscillation, a well-known effect that results from the nonlinear time-delay integro-differential equations that govern cavity dynamics. Such behavior poses a risk of destabilizing the vehicle trajectory. Additionally, while the vehicle remains in a partially cavitating condition, the basic force model must be modified to account for the wetted afterbody. This article presents an overview of these effects, along with a model for dynamics simulation and rudimentary approaches to control.