The estimation of hydrodynamic coefficients of an autonomous underwater vehicle by comparing a dynamic mesh model with a horizontal planar motion mechanism experiment

Abstract

This study aims to establish a dynamic mesh model based on the horizontal planar motion mechanism (HPMM) test and provide a comprehensive database of hydrodynamic coefficients for the autonomous underwater vehicle (AUV) numerically and experimentally. A series of HPMM tests in National Cheng Kung University's towing tank validated the simulation results. The dynamic mesh model can be performed on oscillation motions of the yaw mode, the pitch mode, and the roll mode by adding a series of comprehensive user-defined functions (UDFs). The test of straight-line motion with constant drift angles, the pure surge test, the pure yaw test, the pure pitch test, the pure yaw test with a constant drift angle, and the pure pitch test with a constant drift angle are all available for the yaw and pitch modes. In addition, the pivot roll test is included in the roll mode. After measuring forces and moments from an individual HPMM test, the hydrodynamic coefficients can be derived by means of Fourier analysis and the least-square method. Since most numerical results are reasonably in good agreement with the experimental data, applying the proposed dynamic mesh model to the simulation of the HPMM tests in the towing tank can be demonstrated.