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Hydrogen refueling station (HRS) is an essential part of the infrastructure for promoting the hydrogen economy. Since hydrogen is a flammable and explosive gas, hydrogen released from high‐pressure hydrogen storage equipment in HRS will likely cause combustion or explosion accidents. Studying high‐pressure hydrogen leakage in HRS is a prerequisite for promoting hydrogen fuel cell vehicles and HRS. A computational fluid dynamics (CFD) model of an HRS in a demonstrated project in Ningbo, China, was established on the ANSYS FLUENT software platform. The CFD model for hydrogen leakage simulation was validated by comparing the simulation results with experimental data in the literature. The effects of the direction and mass flow rate of the hydrogen leakage jet, as well as the direction and speed of ambient wind, on hydrogen diffusion behavior were investigated. The spreading distances of the flammable hydrogen cloud were predicted using an artificial neural network for horizontal leakage. The results show that the jet direction strongly affected the flammable cloud flow. The greater the mass flow rate of the leak, the greater the hydrogen dispersion distance and the volume of the flammable hydrogen cloud. At a hydrogen leakage mass flow rate of 4.5589 kg/s, the volume of the hydrogen flammable cloud reached 6,140.46 m3 at 30 s of leakage. The ambient wind speed has complicated effects on spreading the flammable cloud. The wind makes the flammable cloud move in certain directions, and the higher wind speed accelerates the diffusion of the flammable gas in the air. The results of the study can be used as a reference for the study of high‐pressure hydrogen leakage in HRS and will play an important role in the safe demonstration of the studied project. [ABSTRACT FROM AUTHOR]

Compression is currently the preferred storage technology for hydrogen vehicles due to its quick refueling process and relatively simple design. However, the temperature rise associated with fast filling must be controlled to ensure its safe operation. This article discusses general heat transfer models based on the mass and energy balance equations for the refueling process of the compressed hydrogen storage tank. Depending on the way of treating the geometric structure of the storage tank, three general lumped parameter models of single-zone (hydrogen), dual-zone (hydrogen and tank wall) and triple-zone (hydrogen, tank wall liner and shell) are built. The general single-zone and dual-zone models are reduced to some special cases which have been published. Under adiabatic and diathermic conditions, four models, including single-zone, dual-zone single-temperature (hydrogen temperature), dual-zone dual-temperature (hydrogen and tank wall temperatures) and triple-zone triple-temperature (hydrogen, tank wall liner and tank wall shell temperatures), are implemented using Matlab/Simulink™ to simulate the hydrogen refueling process under corresponding conditions. Analytical solutions of single-zone and dual-zone lumped parameter models are derived. The temperature rises of the compressed hydrogen storage tank are described by comparing the analytical solution with the numerical solution. The proposed general models were applied to estimate the final hydrogen temperature and mass, the SOC, the refueling time, and the precooling hydrogen temperature, reviewed and summarized in this article. The analytical solutions of the heat transfer during hydrogen refueling can provide theoretical guidance for improving the refueling efficiency and enhancing refueling safety. • Three general lumped parameter models of thermodynamic and heat transfer were built. • The models are single- (H2), dual- (H2 and tank) and triple-zone (H2, liner and shell). • Analytical solutions of single- and dual-zone lumped parameter models are derived. • Lumped parameter models are validated under the adiabatic and diathermic conditions. • The models and their solutions are widely applied for refueling hydrogen vehicles. [ABSTRACT FROM AUTHOR]