Abstract:With the widespread application of ROV in many fields of ocean research and operation, its hydrodynamic numerical calculation has attracted more and more attention. Based on the Computational Fluid Dynamics (CFD) theory, according to the Shear Stress Transfer(SST) turbulence model numerical solution and the principle of Reynolds equation(RANS), the second-order damping coefficient, linear damping coefficient and additional mass of ROV were calculated by the cut volume meshes method, so as to establish the three-degree-of-freedom ROV dynamic model. The hydrodynamic value of a single ducted propeller was calculated with the help of software STARCCM+, and the hydrodynamic performance of the ducted propeller was calculated by considering the influence of ROV. On this basis, the matching of ROV's power and resistance was conducted, and a speed prediction method based on regression curve method was proposed to realize the ROV's speed prediction. The results show that, the sum of the thrust generated by the individual propeller can be used as the total thrust of the ROV; Under the condition of fixed propeller speed, multiple speed points are set near the estimated speed, the iteration method and regression curve method were used to determine the speed point with equal thrust and resistance at this speed, so as to realize the ROV speed prediction at different propeller speeds.