A one- and three-dimensional coupled model and simulation investigation for the large-scale oil-heating type Mg-based hydrogen storage tank

Abstract

A large-scale oil-heating type Mg-based hydrogen storage tank is the key device for the high-efficiency and high-safety Mg-based solid hydrogen storage and transportation. However, the complicated heat and mass transfer in the Mg alloy bed and oil tube during the hydrogen desorption process impede the design of high-performance hydrogen storage tanks. In this work, a one- and three-dimensional coupled model considering the impact of oil velocity and temperature on the internal heat and mass transfer was developed to simulate the hydrogen desorption process of large-scale oil-heating type Mg-based hydrogen storage tanks. This model was then solved by the finite element method, and the simulation results agreed well with the experimental data obtained from an Mg-based hydrogen storage tank. Moreover, simulation results indicate that the oil velocity has a considerable impact on the hydrogen desorption performance of the Mg-based hydrogen storage tank, and a recommended oil velocity of 4 m s−1 was identified. In addition, high oil temperature and low hydrogen desorption pressure benefit the hydrogen desorption performance, thus should be determined by the application scenarios. Besides, the complete hydrogen desorption time was barely affected by the initial bed temperature, which is suggested as ≥ 573 K to meet the high rate requirement of hydrogen supply, otherwise as room temperature to reduce energy costs. The model and simulation results presented in this work provided a foundation for the design of high performance large-scale oil-heating type Mg-based hydrogen storage tanks that can be applied practically in the field of hydrogen energy.