Experimental investigation of clam water impact on flatted-bottom seafloor mining tool

Abstract

A test rig for constant velocity water entry experiments was developed that drives a flatted-bottom section attached on six degree of freedom(6-DOF) platform to enter the water vertically at near constant velocity. The experiment system, which consists of drive and actuation system, water pool, model test sections, load cell, and control system, was presented. Water entry forces of different velocities were measured during impact process, and for each test case, three runs were performed with the same motion program to check the repeatability of the force readings. The experiment results are compared with two-dimensional (2D) CFD simulation methods for flatted-bottom rigid bodies with constant entry velocity. Experimental results indicate that the impact forces mainly depend on water entry velocities. It is concluded that the feasibility and accuracy of simulation methods has been validated.

Keywords

water entry / water impact / constant velocity / deployment

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