Fluid structure interaction of submerged metallic and composite plates subjected to low velocity impact loading

Abstract

An instrumented low velocity impact rig has been used to acquire experimental data for impacts in air and underwater for both metallic and composite plates when subjected to a low velocity drop-weight impact with a 2 kg steel impactor. Initial impact studies were conducted in air and then repeated for submersed conditions underwater. Experimental results are compared for all tests with numerical solutions and are found to be in good agreement. For underwater impact, the numerical model incorporates the use of an Eulerian formulation for the water with a coupled fluid-structure interaction (FSI) algorithm. The effect of the water surrounding the target plates was found to reduce the peak accelerations and also reduce the overall impact duration when compared to the same impacts in air. X-Ray imagery of the composite plates also showed visibly reduced damage for the submersed test specimens. This research provides data on the impact response of metallic and composite materials, and validates numerical methodologies for use in future work on FSIs which show strong potential for relevant industrial applications.