Thermo-mechanical investigation of composite high-pressure hydrogen storage cylinder during fast filling

•Theoretical model to study the temperature rise characters of the composite cylinder.•CFD model to predict the thermal behaviors of the 70 MPa fast filling process.•Finite element analysis of the coupled thermo-mechanical properties.•The aluminum liner deforms plastically so as to relieve the thermal stress effectively.

The fast refueling process of hydrogen results in a significant temperature rise within the composite hydrogen storage cylinder, which may decrease the cylinder state of charge and cause complicated thermo-mechanical behaviors of the composite structure. This study presents an analytical model, as validated by computational fluid dynamics (CFD) simulations, to study the thermal properties of composite hydrogen storage cylinder during fast filling process. A simple analytical formula for the gas temperature within cylinder and the temperature distribution in solid walls are obtained, which show intuitively the effects of different material and geometry parameters on thermal properties of the cylinder. Furthermore, a 3D finite element analysis (FEA) model, using the analytical results of temperature distribution, is proposed to investigate the coupled thermo-mechanical behaviors of the cylinder. FEA results reflect that the plastic behavior of aluminum liner effectively isolate the thermal stress, and helps to relieve the thermal effects on the whole cylinder in a large extent.