Computational Fluid Dynamics Simulation of Filling a Hydrogen Type 3 Tank at a Constant Mass Flow Rate

Abstract

Hydrogen storage in high-pressure tanks can be performed with different filling strategies. Many studies have been carried out on supplies with increasing pressure rates. The present work aims to carry out CFD numerical simulations, using Ansys Fluent®, in a type 3 tank of 70 MPa normal working pressure (NWP) using a constant flow rate, to analyze the influence of inlet key parameters such as initial temperature, mass flow rate, and material properties on the evolution of temperature, pressure, and velocity. From the analysis of the results, it was possible to discover linear relationships between the increase in the total equilibrium temperature and the final hydrogen temperature, as well as a linear increasing relationship between inlet and final temperatures when the equilibrium temperature was fixed. Considering fully adiabatic walls resulted in a significant increase in temperature with no predictable pattern. The difference between total and static temperatures found in the inlet tube decreased with the decrease in mass flow rate and subsequently the Mach number. The choice of a polymer for the tank lining led to higher temperatures when compared to an aluminum lining.