Inspired by the study of Rao et al. (2019), the aerodynamics of a simplified frigate is investigated experimentally. The natural wake flow dynamics is shown to be bi-stable at zero yaw angles, at both the rear of the ship superstructure and the stern. The bi-stable dynamics is strongly weakened at the stern when the ship is lifted off the ground in the free-stream. Perimetric cavities of sufficient depth at the rear of the superstructure are able to suppress the bi-stable dynamics and to symmetrize the air-wake flow at both the superstructure and the stern. The base pressure increases with the cavity depth while the drag force slightly decreases. Our study experimentally confirms that perimetric rear cavities offer efficient devices for passive flow control strategies of the aerodynamic air-wake flow of bodies of complex geometries subject to bi-stable dynamics.

受到 Rao 等人研究的启发。(2019)，对简化护卫舰的空气动力学进行了实验研究。自然尾流动力学被证明在零偏航角下是双稳态的，在船舶上层建筑的后部和船尾。当船在自由流中离开地面时，双稳态动力学在船尾被强烈削弱。上层建筑后部足够深度的周向空腔能够抑制双稳态动力学并使上层建筑和船尾的气流对称化。基础压力随着腔深度的增加而增加，而阻力略有减少。