Investigation on the changes of pressure and temperature in high pressure filling of hydrogen storage tank

Abstract

Hydrogen as fuel has been considered as a feasible energy carry and which offers a clean and efficient alternative for transportation. During the high pressure filling, the temperature in the hydrogen storage tank (HST) may rise rapidly due to the hydrogen compression. The high temperature may lead to safety problem. Thus, for fast and safely refueling the hydrogen, several key factors need to be considered. In the present study, by the thermodynamics theories, a mathematical model is established to simulate and analyze the high pressure filling process of the storage tank for the hydrogen station. In the analysis, the physical parameters of normal hydrogen are introduced to make the simulation close to the actual process. By the numerical simulation for 50 MPa compressed hydrogen tank, the temperature and pressure trends during filling are obtained. The simulation results for non-adiabatic filling were compared with the theoretically calculated ones for adiabatic conditions and the simulation results for non-adiabatic filling were compared with the simulation ones for adiabatic conditions. Then, the influence of working pressure, initial temperature, mass flow rate, initial pressure and inlet temperature on the temperature rise were analyzed. This study provides a theoretical research basis for high pressure hydrogen energy storage and hydrogenation technology. • An accurate equation for temperature rise calculation of hydrogen has been put forward and validation of the fitting formula for final temperature with experimental data is conducted. • In order to verify our simulation model, the pressure variation during a filling process was compared with the experimentally measured pressure values. • The simulation results for adiabatic and non-adiabatic filling were compared with the theoretically calculated ones for adiabatic conditions. • Through coupling strategies of pre-cooling and filling rate can effectively suppress the temperature rise inside the hydrogen tank.