The hydrodynamic characteristics and continuous skipping control strategy of skipping flight vehicle shaped by waverider configuration

Inspired by the classical skipping of stones and disks, recent studies have proposed the concept of a skipping flight vehicle. This type of flight vehicle typically adopts a configuration with more practical applications, providing a new approach to near-water-surface flight. However, since the aircraft-inspired configuration does not possess the axisymmetry and self-spinning characteristic of the disk, the skipping flight vehicle shows different hydrodynamic and motion characteristics, which makes its design more challenging. As an investigation on this challenge, this study performs a numerical investigation on the fluid mechanisms of a waverider-like skipping flight vehicle using a volume of fluid model and a six-degree-of-freedom dynamic fluid-body interaction solver, coupled with overset mesh and adaptive mesh refinement. The validation of the numerical simulation model is verified by comparing the vehicle's attitude and cavity shape with experimental observations. The results indicate that during a single skipping jump, the direction of the pitching moment is determined by the position of the center of pressure, which varies with the location of the high-pressure region on the bottom of the vehicle. This high pressure originates from two distinct sources, namely slamming and stagnation, which act in different stages of the skipping process. Meanwhile, simulations with different water-entry angles reveal that both large and small inclination angles hinder stable skipping initiation, while moderate angles (3–5 deg) enable continuous skipping. To ensure the success of continuous skipping jumps, a damping moment is implemented to suppress residual pitch rate between skipping jumps, which achieves good results.