Dynamic Analysis and Force Calculation of Seafloor Mining Tool Based on the Heave Motion of Mining Support Vessel in the Launching Process

In the present paper, a typical seafloor mining tool (SMT) is demonstrated. With considering the influence of ocean currents and ocean wave, the force analysis is carried out to SMT. There are five forces that effect SMT, they are as following: gravity, buoyancy, hydraulic drag force, tension of the riser and added mass forces. The results of force analysis strongly suggest that the added mass forces impose an important influence on heave motion of SMT. Thus the added mass effect is mainly investigated within potential flow theory. According to the analysis, added mass play an important role in the deployment of SMT, the effect of which cannot be omitted. A hydrodynamic model is developed to simulate the heave motion of SMT; Results of the simulation verify the correctness of the force analysis.