Numerical Simulation of the Thermal Response of the Composite Layer of Type III Gas Cylinders Under Local Thermal Impacts

The safety performance of high-pressure hydrogen storage composite cylinders under localized thermal impacts has attracted wide attention. In order to evaluate the thermal response of composite gas cylinders under different fire scenarios, a finite element model considering the heat conduction of the composite layer of the cylinder, the diffusion of the decomposed gas and the heat absorption of the decomposition reaction was established using the UMATHT subroutine in ABAQUS. The model is validated by comparing the data of composite laminates affected by fire in literature. Then, the model is used to analyze the temperature and decomposition degree of the winding layer of the gas cylinder under different heat flows. Results reveal that the higher the heating heat flux received by the gas cylinder, the higher the temperature and degree of decomposition of the winding layer after heating is completed. Under a heat flow of 80 kW/m², as the heating time prolongs, the surface temperature of the gas cylinder continues to rise. In addition, the relationship between the temperature and degree of decomposition of the gas cylinder winding layer is related to the depth, peak decomposition rate, and time to reach the peak. This paper provides a feasible approach for assessing the thermal response of the composite layers in Type III hydrogen storage cylinders under fire conditions.