Study on Coupled Motion of Floating Hydrogen Storage Platform with Liquid Hydrogen Sloshing

The production of hydrogen on offshore platform can decrease reliance on the power grid, mitigate transmission losses of electricity, and diminish investment costs for subsea cables. In this study, the hydrodynamic performances of platforms equipped with two types of tanks separately are evaluated and are comprehensively compared with each other. The Volume of Fluid (VOF) two-phase flow model and the Shear-Stress Transport (SST) k–omega turbulence model are applied to simulate the motion responses of the C-type and Moss-type tanks under the same excitation force of platform based on the time-frequency response results of platforms. Comparisons are made among the shape of the liquid hydrogen surface, variations of the wall pressures, changes of the gas-liquid temperatures, and the pressure drop phenomena induced by phase changes inside the tanks. The results indicate that the interaction between wave-induced excitation force and sloshing force from tanks can either increase or decrease the amplitude of platform’s motion. Meanwhile, the thermodynamic responses of liquid hydrogen sloshing inside the tanks correlate positively with the dynamic behavior. Compared with Moss-type tanks, the sloshing of liquid hydrogen in C-type tanks is more intense, accompanied by jetting and breaking wave phenomena. For the C-type tanks, the substantial increase in interfacial area significantly enhances phase change condensation and heat transfer, leading to the rapid decline in temperature and pressure inside the tanks. The results of this study can provide valuable insights for the future design of floating hydrogen storage platform and the selection of tanks on the platform.