Numerical simulation of near-surface turn maneuver of a generic submarine

Aiming at the actual demand of improving the numerical simulation of the unsteady motion of submarines in maneuvering conditions, the overset grid is used to model six degrees of freedom coupling motions of the submarine and the independent motion of each control plane, and the sliding grid is used to simulate the rotation of the propeller, to carry out the research on the numerical simulation approach of a generic submarine in near-surface maneuvering condition. The VOF method is utilized to capture the free surface. By comparing the submerged turn maneuver numerical simulation results of typical dynamics parameters with the experiment's results, the practicability of the approach for engineering prediction is verified. Then the simulations of near-surface maneuvers under different submergence depths are conducted, and the influence of submergence depth on kinematics and dynamics parameters of Joubert BB2 in maneuvering conditions are analyzed. Results demonstrate that the control performance of the stern planes will be sharply degraded when maneuvering too close to the free surface, resulting in a significant increase in the tactical diameter of the turn maneuver. The research can guide the prediction and evaluation of submarine maneuverability and seaworthiness. It is beneficial for the improvement of free running submarine model tests.