高速入水可压缩流-固耦合建模及材料响应机制OA

The high-speed water entry of projectiles involves severe transient impact,phase-change cavitation and fluid-structure interaction,which directly affect the safety of naval equipment and the performance of underwater detection.To address the limitations of conventional theories in characterizing impact loads and fluid-material interaction mechanisms during high-speed water entry process,this study focuses on the conjoined influence of fluid compressibility and material properties on impact loads,and conducts numerical simulations of high-speed vertical water entry.A combined experimental and numerical approach is adopted to establish a multiphase fluid-structure framework,in which a compressible-flow solver coupled with a VOF surface-tracking routine captures cavitation inception and collapse.Simulations of high-speed water entry are performed for projectiles made of rigid body,hyper-elastic elastomer,and aluminum foam considering nonlinear material constitutive models and dynamic problems.The validity of the proposed model is verified through experiments.The results show that the established model successfully captures the fluid-structure interaction and compression wave propagation characteristics.Neglecting fluid compressibility will significantly underestimate flow resistance and overlooks the energy dissipation mechanism of cavity collapse,leading to an overestimation of projectile displacement and velocity by the incompressible model.Furthermore,the regulatory effect of material properties on impact responses is revealed.The stiff steel concentrates impulse into intense shock fronts,whereas the elastomer and the foam absorb kinetic energy through large-deformation and progressive pore collapse,reducing wave speed and generating dispersed low-pressure fronts that mitigate structural damage.This study clarifies the mechanism of impact regulation utilizing material deformability and compressibility effects,providing theoretical support for the design of underwater high-speed impact protection systems.