A study on the flow-pressure characteristics & temperature changes of a novel type of pressure regulator for hydrogen decompression

Abstract

Hydrogen storage and transportation need to be conducted in high-pressure systems, making the study of high-pressure hydrogen pressure-reducing valves crucial. This paper presents the design of a new high-pressure hydrogen reducing valve (HPRV) suitable for the hydrogen circulation system of a hydrogen refueling station. It investigates the impact of spool opening, structural type, and outlet pressure on the temperature and flow rate of hydrogen within the valve body. A computational fluid dynamics (CFD) model is established to optimize and simulate the valve body structure. The results indicate that as the spool opening increases, the maximum turbulent dissipation rates of the primary and secondary HPRVs exhibit opposite trends. The hydrogen temperature and flow rate show consistent variation trends under the different outlet pressures. For different spool structures, the highest temperatures for Needle cone spool, expanding arc cone spool, and Recessed arc cone spool are 351.91 K, 375.12 K, and 368.23 K, respectively, with temperature decreases and flow rate increases. Overall, the peak temperature consistently appears at the primary spool, increasing by 20.07 %, 28.04 %, and 25.67 %, respectively. Additionally, the paper discusses the variation in physical parameters within the internal flow field and their potential effects on the valve body structure, providing a reference for the optimization design of HPRVs in hydrogen refueling stations.

Keywords

• Hydrogen pressure reducing valve
• Flow field state
• Temperature changes
• Pressure reducing performance
• Numerical simulation