On the effect of a rigid boundary on the supercavity profile

The features of cavity formation during striker motion near a rigid boundary are considered. Experimental results demonstrating cavity development in the presence of the rigid wall are presented. The time dependences of the supercavity cross-sectional diameters and the vertical displacement of the supercavity cross-sectional centers are plotted. Qualitative and quantitative analysis of the rigid boundary effect on the supercavity profile behind the striker moving in water is performed. It has been shown that the supercavity is repelled from the rigid wall during the expansion phase and it is attracted to the wall during the contraction and collapse phases. Distortion of the supercavity boundary is observed not only when the striker has overpassed the rigid wall but also when it is moving above the wall. In some cases, this may affect the striker trajectory. The obtained results can be used to verify mathematical models describing the motion of a solid body under conditions of supercavitating flow.