空投鱼雷斜入水冲击动力建模及仿真分析

Modeling and Simulation Analysis of Oblique Water-entry Impact Dynamics of Air-dropped Torpedo

以入水弹道学和入水冲击理论动力学为基础,基于势流理论,针对入水体与流体耦合面的精确外形,建立空投鱼雷斜入水冲击初期动力学冲击模型,模型中引入体现液面隆起现象的沾湿因子,充分考虑入水冲击引起液面隆起的影响,采用精确形体法对入水冲击动力学模型和运动学模型进行解耦,在数值计算过程中应用了侵深步进法求解每一侵深步进的动态行为,以提高计算效率。然后,通过分析雷头截头尖拱体的高速斜入水冲击算例,表明在斜入水冲击初期采用精确形体法正确性和有效性;同时分析了液面隆起现象对轴向负荷和弯矩的影响,以及尖拱体的缓冲效应和截头尖拱体的防弹跳作用。

The paper is based on water- entry dynamics and ballistic theory, and a wetted correction factor is introduced to substitute free water surface with equivalent water surface to represent the true water pile phenomena. An oblique water - entry impacting model of disk ogive coupled with dynamic and ballistic model is established using exact body shape method, fully taking into consideration of the local uprise of water and fluid viscous drag. The water - entry depth marching is employed to simulate and compute with a constant wetted correction factor and an inceptive condition of oblique water entry. The result of theoretic implementation of the exact body shape method is verified by the example for torpedo water - entry model installed ogive or disk ogive. And at same time, it provides valuable references for studying whip, ricochet and the cushioning technology of water - entry impact.