(279d) A Dynamic Model for Designing Optimal Condition of the Tank on Hydrogen Carrier

This study presents a dynamic model developed to analyze the storage capacity of hydrogen, holding time, and hydrogen loss depending on storage pressure of the tank. The escalating concern regarding climate change and the growing demand for environmentally sustainable energy has led to an increasing interest in hydrogen and hydrogen carrier to transport hydrogen by the ship. We consider the cryogenic pressure tank that is initially filled with 99.81% para hydrogen, whose temperature and pressure increase and which is brought to supercritical condition by external heat ingress. The ortho-para equilibrium of hydrogen is primarily determined by temperature; however, experimental evidence has demonstrated that the conversion rate of para-to-ortho hydrogen is influenced by density and temperature. The conversion rate of endothermic para-to-ortho conversion and absorbed heat are affected by the initial pressure, amount of hydrogen, temperature and external heat ingress. These variables have a significant impact on the duration of time that the tank can hold hydrogen before it reaches its maximum allowable pressure and the amount of boil-off gas loss to maintain the tank pressure. Based on this model, we aim to derive optimal storage condition for 10K hydrogen carrier during its voyage considering the amount of stored hydrogen, external heat, and boil-off gas loss.