Numerical simulation of subsonic and transonic water entry with compressibility effect considered

• Published in: Ocean engineering Vol. 281; p. 114984
• Main Authors: Wu, Qin, Wang, Kai, Kong, Decai, Zhang, Jiayue, Liu, Taotao
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.08.2023
• Subjects: Cavity; Compressibility; Subsonic; Transonic; Water entry; Subsonic; Water entry; Compressibility; Cavity; Transonic
• ISSN: 0029-8018; 1873-5258
• DOI: 10.1016/j.oceaneng.2023.114984

The purpose of this study is to analyze the subsonic and transonic water entry of the axisymmetric body with compressibility effect considered. The water-entry processes of axisymmetric body are numerically investigated, with Tait state equation and energy equation used to describe the compressibility of the liquid. Reasonable agreement has been obtained between the numerical results and the experimental measurements of trajectory, velocity and acceleration. The cavity evolution and dynamic characteristics of subsonic cases are investigated for vertical and oblique water-entry. The results show that the maximum drag coefficient of the oblique water entry is lower, and it is affected by a large moment which causes pitch angle and trajectory inclination angle to change significantly. In the oblique transonic conditions, the effect of compressibility of the liquid on the dynamic flow characteristics is analyzed. On this basis, the influence of entry angle on the hydrodynamic characteristics is investigated. It is concluded that the water-entry angle has a more significant influence on the trajectory characteristics. •Investigate the flow structure and dynamic characteristics of subsonic water-entry cases for vertical and oblique water-entry.•Analyze the effect of compressibility of the liquid on the dynamic flow characteristics of transonic water-entry cases.•Improve the understanding of the influence of entry angle on the hydrodynamic characteristics with compressibility considered.