A Thermodynamic Analysis of Refilling of a Hydrogen Tank
Jiann C. Yang
A thermodynamic analysis of refilling of a gaseous hydrogen fuel tank is described. This study may lend itself to the applications of refilling a hydrogen storage tank onboard a hydrogen fuel cell vehicle. The gaseous hydrogen is treated as an ideal or a non-ideal gas. The refilling process is analyzed based on adiabatic, isothermal, or diathermal condition of the tank. A constant feed-rate is assumed in the analysis. The thermodynamic state of the feed stream also remains constant during refilling. Ideal-gas assumption results in simple closed-form expressions for tank temperature and pressure and other parameters. The non-ideality behavior of high-pressure gaseous hydrogen is addressed using the newly developed equation of state for normal hydrogen, which is based on the reduced Helmholtz free energy formulation. Sample calculations are presented using initial tank and feed stream conditions commensurate to practical vehicular applications. Ideal-gas assumption always results in under-prediction of the tank temperature and pressure irrespective of the refilling condition.
A Thermodynamic Analysis of Refilling of a Hydrogen Tank, International Journal of Hydrogen Energy, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=901791
(Accessed December 10, 2023)