Research on Hydrodynamic Modeling and Simulation of Streamlined Autonomous Underwater Vehicle based on CFD Method

This paper proposes a novel computational fluid dynamics (CFD) simulation method and applies it to solve the main hydrodynamic coefficients of a streamlined autonomous underwater vehicles (AUVs). The steady-state solution method is combined with the small-amplitude unsteady solution method to solve the viscous and inertial hydrodynamic coefficients of the AUV, respectively. The steady-state motion of the AUV is simulated in Star CCM+ for each degree of freedom of direct and rotational motion at different velocities and angular velocities, and the velocity and drag data are curve-fitted using least squares to solve the main linear and nonlinear AUVs Viscous hydrodynamic coefficient. In Star CCM+, the unsteady motion of small amplitude pure heave, sway, surge, and yaw motion of AUV is simulated by the method of combining dynamic and static meshes. The periodic curves of the time and drag data were fitted in MATLAB using a Fourier series to obtain the main inertial hydrodynamic coefficients of the AUV by separating the fundamental term from the results. The hydrodynamic coefficients obtained from the simulation are compared with the main hydrodynamic coefficients calculated in FLUENT to verify the feasibility of the CFD calculation method proposed.