Heat Transfer Analysis of High Pressure Hydrogen Tank Fillings

Fast fillings of hydrogen vehicles require proper control of the temperature to ensure the integrity of the storage tanks. This study presents an analysis of heat transfer during filling of a hydrogen tank. A conjugate heat transfer based on energy balance is introduced. The numerical model is validated against fast filling experiments of hydrogen in a Type IV tank by comparing the gas temperature evolution. The impact of filling parameters, such as initial temperature, inlet nozzle diameter and filling time is then assessed. For the considered Type IV tank, the results show that both a higher and lower tank shell thermal conductivity results in lower inner wall peak temperatures. The presented model provides an analytical description of the temperature evolution in the gas and in the tank shell, and is thus a useful tool to explore a broad range of parameters, e.g., to determine new hydrogen filling protocols.