Numerical simulation study on a novel cooling system for the membrane head of high-pressure hydrogen diaphragm compressors

Hydrogen energy is regarded as a promising substitute for fossil fuels owing to its high energy efficiency and environmentally friendly characteristics. Hydrogen compressors are core components in the hydrogen refueling stations. However, a large amount of heat is produced in the diaphragm compression process, which negatively affects its thermodynamic performance and the reliability of the hydraulic oil. This paper focuses on addressing such problems in conventional models, such as uneven temperature distribution in the membrane head, excessively high discharge temperatures, and susceptibility to membrane head rupture. A novel membrane head wrap-around cooling structure is developed. Through the establishment of a lumped parameter model and the construction of an experimental test platform, a systematic study and analysis of the performance of this innovative compressor are conducted. Both numerical simulations and experimental validation demonstrate that this cooling system can significantly reduce discharge temperatures. The error between model predictions and the experimental results is within 7%, validating the effectiveness of the structure for compressor thermal management. When the coolant temperature decreased from 50 °C to −5 °C, the discharge temperature was lowered by up to 39.3 °C. When the coolant flow rate increases from 0.12 to 0.48 kg/second, the discharge gas temperature decreases by 12.5%.