Virtual Prototype Modeling and Fast Dynamic Simulation of the Complete Integrated Sea Trial System for Deep-Ocean Mining

Abstract

The virtual prototype model for fast simulation analysis of the complete integrated sea trial system for deep ocean mining is built up based on single-body model of the seafloor tracked miner and discrete element model of the pipeline system. Dynamic simulation analysis is performed and investigated taking into account the interactions between each subsystem and corresponding complex ocean environment. Both for the tracked miner and the pipeline system, two different modeling and simulation methods are considered and compared with regard to computational efficiency and solution accuracy. Focusing mainly on the integrity and rapidity of the dynamic simulation of the total mining system, the seafloor miner is preferred to be modeled as a single-body with 6 degrees of freedom, which allows real-time simulation, while the interaction model between the miner and seafloor soft cohesive soil is built based on the theory of terramechanics and with consideration of seafloor soil special mechanical characteristics. The pipeline subsystem including the lifting pipe, pumps, the buffer and the flexible hose is chosen to be built as 3-D discrete element model which is divided into rigid elements linked by flexible connectors, and external forces such as the hydrodynamic forces due to the maritime sea current, the buoyancy forces acting at discrete locations on the flexible hose are considered. The simulation analysis results are obtained and discussed, which in a way can reflect the actual working conditions and provide useful guidance and reference for the practical deep ocean mining system design and operation.