基于流固耦合的航行体高速入水规律研究

Study on High-speed Water Entry Law of Trans-media Vehicle Based on Fluid Solid Coupling

针对航行体高速入水过程中的流固耦合问题,采用有限元软件LS-DYNA中基于任意拉格朗日-欧拉(Arbitrary Lagrange-Euler,ALE)的流固耦合方法,首先对美国MK25鱼雷模型的入水过程进行动态模拟,获取模型入水过程中的冲击效应和随时间变化的过载,得到不同时刻的流固耦合形态,验证了仿真方法的有效性。然后针对某航行体模型的质量、缩比效应、速度、入水角度等因素进行了仿真研究,结果表明决定高速入水过载的最重要因素是入水速度,入水角度对过载的影响相对较小,分析缩比结果验证了缩比定律的有效性。

To address the problem of fluid solid coupling during vehicles’high-speed water entry,based on LS-DYNA software using fluid solid coupling method of ALE,the water entry process of US MK25 torpedo model is simulated.The impact effect and acceleration varying with time are both obtained.The results exhibit different forms of fluid solid coupling,and thus the validity of the simulation is verified.Then the influences of mass,scaling effect,velocity,and water entry angle for trans-media vehicle model are simulated using the ALE method.The simulation results show that the key point to determine acceleration of water entry is velocity,where the influence of water entry angle is minor.The results also verify the validity of scaling law.