%0 Journal Article %A LI Yiguo, WANG Cong, WU Yuyan, CAO Wei, LU Jiaxing, HE Qiankun %T On the Motion Characteristics of Cavity Wall in the High-speed Water Entry of Trans-media Vehicle %D 2022 %R 10.12382/bgxb.2021.0145 %J Acta Armamentarii %P 574-585 %V 43 %N 3 %X The high-speed water entry of a trans-media vehicle involves unsteady multiphase flow,which has strong theoretical research significance and engineering application value. In order to obtain the motion characteristics of cavity wall in the high-speed water entry of the vehicle,an experimental study is carried out on the high-speed water entry of a rotating body model. The influences of different excitation effects on the evolution characteristics of the cavity are analyzed. The relationship between the extreme displacement of the cavity and the dual independent variables including attitude angle and cavitation number is extracted,for which surface fitting is performed. The experimental results show that both the splash ring above the free liquid surface and the relative displacement of cavity wall below the free liquid surface are approximately symmetrical during the vertical water entry. The splash ring on the upstream side is significantly larger than that on the downstream side during the non-vertical water entry. When the cavitation number is 0.008 5-0.008 8,the positive excitation dominated by energy transfer and cavitation leads to the extreme displacement of cavity wall on the upstream side,and the smaller the attitude angle is,the stronger the positive excitation effect is. Below the 3D depth position,the negative excitation effect of inhalation effect can be ignored relative to the positive excitation effect of cavitation effect. The extreme displacement on the downstream side is approximately symmetrical,and that on the upstream side is approximately linear on the fitted surface. %U http://www.co-journal.com/EN/10.12382/bgxb.2021.0145