Implementation for Model of Adsoptive Hydrogen Storage Using UDF in Fluent

This paper builds an axisymmetrical geometry model and simulates the charging, domancy, discharging and domancy processes of hydrogen storage tank based on activated carbon bed in a steel container at room temperature (302K) and medium storage pressure (10 MPa). The CFD model is based on the mass, momentum and energy conservation equations of the hydrogen storage system formed of gaseous and adsorbed hydrogen, activated carbon bed and steel tank wall. The adsorption model is based on Dubinin-Astakov adsorption isotherms. The simulation is implemented using a finite volume method through the computational fluid dynamics commercial software Fluent. User defined functions (UDFs) hooked in Fluent software are given to set the boundary conditions or modify the mass and energy conservation equations.The simulating results have good agreement with experimental results. Results show that the temperature of central region is higher than that near the wall during the charging process,while the temperature of central region is lower than that near the wall during the discharging process.The amount of adsorbed hydrogen is greater than that of the compressed gaseous hydrogen. Hydrogen storage by adsorption on high surface area activated carbon has obvious advantages.