Cavitation bubble dynamics and structural loads of high-speed water entry of a cylinder using fluid-structure interaction method.

• Fluid–Structure Interaction method for predicting high-speed water entry problem is • Comparison between CFD and FSI of high-speed water entry of cylinder are investigated. • Detailed description of von Mises stress over the cylinder at high entry velocity is presented. • The effects of the water-entry velocity on the cavity evolution, motion, and structural response of the cylinder are analyzed. This paper describes an investigation of the motion, structural response, and cavitation bubble evolution of a cylinder in the high-speed water entry (HSWE) process using a fluid-structure interaction (FSI) method. The effectiveness and accuracy of the FSI method are verified by comparison with experimental results available in the literature. The results show that the cylinder structure is deformed when considering the coupling effect between the fluid and the structure, and the impact load during water entry presents obvious fluctuation characteristics. Meanwhile, the von Mises stress distribution on the two end faces of the cylinder is in a ring shape and propagates as the structure deforms. Moreover, the cavitation bubble dynamics, motion and structural loads of the cylinder under different water entry velocities are investigated. The load at the initial stage is greater with the increase of the water entry velocity, which in turn leads to more significant fluctuation characteristics, thereby increasing the deformation of the structure. [ABSTRACT FROM AUTHOR]