Coupled Hydrodynamic Impact and Elastic Response

摘要

A theoretical model for hydrodynamic impact of hulls with hard chines is described. Two distinct conditions are considered: one in the initial stages of impact where the jet-head travels along the hull towards the chine and one in the later stages of impact where the jet-head leaves the body at the chine and outwardly travels across the water surface. Numerical calculations of the hull impact force and acceleration are given and compared with experimental drop test results. the model is then extended to include an internal body, supported by springs and dashpots. The mass of the impacting hull and the mass of the internal body form a two body system subject to the external force of the fluid. The motion of the masses are coupled through the hydrodynamic boundary value problem to form a time dependent hydroelastic impact model. Results applicable to shock mitigation and shock isolation studies are given.