Thermal management on a Type IV storage tank of hydrogen fuel cell electric vehicles during rapid charging

Efficient storage of high-pressure hydrogen gas greatly promotes the fast development of hydrogen fuel cell electric vehicles. However, obvious temperature rise, generated during rapid refueling, brings serious security risk for reliable operation of hydrogen storage tanks. Consequently, a comprehensive analysis of the fast refueling process is essential. In the present study, a Type IV hydrogen storage tank with a pressure of 70 MPa is chosen to conduct the theoretical modeling. The compressibility of high-pressure vapor hydrogen during rapid filling, the turbulent heat transfer at high velocity, the thermal conductivity through the tank structure layers and the convective heat exchange between the storage tank and the ambient, are thoroughly considered in model construction. A one-dimensional unsteady heat transfer theoretical model is specially proposed. The temperatures of hydrogen gas within the storage tank, inner liner and outer wall of the tank, are obtained by node discretization, numerical modeling and iterative solution. Three rapid charging experiments are selected to validate the developed theoretical model. After detailed comparisons, the results show that the temperature rise of hydrogen gas within the storage tank during fast refueling is greatly predicted with the maximum temperature deviations being 5.36 K, 4.83 K and 4.92 K, respectively. Based on the developed theoretical model, the influences of initial settings and filling parameters on the temperature rise of hydrogen storage tanks are investigated. The current work provides a theoretical algorithm for rapidly predicting temperature rise in hydrogen storage tanks, which can guide hydrogen refueling protocols and contribute to enhancing the safety and efficiency of fueling station operations.