开架式水下机器人水动力系数计算与动力学建模

A numerical calculation method for hydrodynamic coefficients based on lattice Boltzmann method (LBM) is proposed for studying the maneuverability prediction and control algorithms of open-frame underwater robot.The steady-state surge motion simulation test and oblique towing simulation test were carried out based on LBM and Reynolds-averaged Navier-Stokes(RANS) methods, respectively, and the feasibility of LBM method was verified by comparing the test results.The motion mathematical models of large amplitude planar motion mechanism(PMM) tests and the hydrodynamic models, including inertial hydrodynamic coefficients, linear and nonlinear viscous hydrodynamic coefficients, were established according to the structural characteristics of remotely operated vehicle(ROV), and the hydrodynamic coefficients in the hydrodynamic models were obtained by using least square method. The standard maneuverability simulation tests were performed, which verifies the validity of the 6-DOF motion equation with hydrodynamic coefficients.Compared with traditional CFD methods, the proposed hydrodynamic coefficients calculation method is not limited by the shape complexity of underwater robot, and the updating issue of complex dynamic mesh in unsteady-state motions simulation is avoided. The calculation period of hydrodynamic coefficients is shortened by the large amplitude PMM simulation tests, and the proposed dynamic model is more available for the research of maneuverability and control algorithms.