航行体高速入水冲击载荷诱导的结构内部响应特性研究

Study on Characteristics of Internal Structural Response of Underwater Vehicles Induced by High-speed Water Entry Impact Loads

摘要:

航行体高速入水时涉及复杂流固耦合作用，产生强瞬态冲击载荷，易引发结构失效。基于 StarCCM+和 ABAQUS 平台，耦合 RANS 方程、VOF 多相流模型、空化模型与 Johnson-Cook 本构模型，建立了高速入水仿真模型。研究表明：入水冲击诱导的应力波在结构内部反复回传形成稳定导波，正向传播产生压缩效应，其轴力极值显著高于逆向传播的拉伸效应；垂直入水速度增大使头部应力分布不均匀性加剧，导致载荷性质由压应力向拉应力转变，促使各截面轴力振幅显著增大，但对应力波传播速度影响有限；斜入水不对称性引发应力波轴向–径向耦合传播，随入水角度减小，传播路径从 Z 字型转为连续扩散模式，轴力幅值趋于平稳而弯矩呈现先增后减趋势。研究结果可为相关结构设计与防护提供参考。

Abstract:

The high-speed water entry of underwater vehicles involves complex fluid-structure interactions and intense transient impact loads，which may induce structural failure. In this study，a numerical simulation model is established based on the STAR-CCM+ and ABAQUS platforms，the RANS equations，VOF multiphase flow model， cavitation model，and Johnson-Cook constitutive model. The research reveals that the water entry impact induces stress waves propagating repeatedly within the structure to form stable guided waves. The axial force peak during forward wave propagation under compression effects significantly exceeds that during reverse propagation under tensile effects. Increased vertical entry velocity exacerbates stress concentration heterogeneity at the head section， causing a transition from compressive to tensile stress dominance and significantly amplifying axial force amplitudes across sections，while minimally affecting stress wave propagation speed. For oblique entry cases，structural asymmetry induces coupled axial-radial stress wave propagation. As the entry angle decreases，the wave transmission path transitions from zigzag to continuous diffusion patterns，resulting in stabilized axial force amplitudes and a bending moment trend characterized by initial increase followed by decrease. These findings provide critical insights for the design and protection of high speed water entry structures.