Changes in holding time depending liquid filling ratio, heat transfer parameters, and shape of the tank

This study simulates the self-pressurization of liquefied hydrogen using a three-element lumped model. We analyze the effects of liquid filling ratio, heat flux distribution, interface heat transfer parameters, and tank shape on pressure build-up, which can vary due to ship transportation conditions. Key findings are: lower liquid levels correlate with faster pressure build-up; the sensitivity of pressure build-up to changes in the heat flux ratio between vapor and liquid is higher during laden voyages compared to ballast voyages; The effect of heat absorption by vapor on pressure build-up is greater than that of BOG caused by heat transfer; and horizontal tanks exhibit the longest holding time. These findings enhance the understanding and prediction of pressure dynamics in liquid hydrogen transportation, aiding the design and optimization of systems for safe and efficient operation.