Computational Fluid Dynamics Analysis of Multistage Hydrogen Compression Process for Hydrogen Charging Station

The utilization of clean hydrogen energy in eco‐friendly mobility systems has gained increasing attention in the pursuit of carbon neutrality. As demand for hydrogen mobility rapidly grows, it becomes essential to expand and distribute hydrogen charging stations, thereby increasing the need for an efficient hydrogen compression process. Among the key components, the hydrogen compressor plays a critical role in enabling hydrogen utilization at refueling stations and must offer high durability, energy efficiency, and operational reliability. In this study, we developed a multistage hydrogen compression process that integrates a diaphragm compressor for low‐ to medium‐pressure compression and a piston compressor for high‐pressure compression, thereby combining the strengths of both types. Using computational fluid dynamics (CFD) simulations, we analyzed the flow characteristics and temperature variations within the compressors and intermediate heat exchangers under different compression ratios. Across three cases with varying diaphragm and piston compression ratios, the overall cooling energy consumption required by the heat exchangers remained nearly constant. However, increasing the compression ratio of the diaphragm stage significantly reduced the total compression energy consumption. Specifically, when the diaphragm’s compression ratio—defined as the final pressure divided by the initial pressure—increased from 4.84 to 7.66, the total energy required to reach the target pressure of 900 bar decreased by 15.6%. Nevertheless, raising the diaphragm’s compression ratio may introduce limitations in terms of system stability and component lifespan. Therefore, a comprehensive evaluation of both energy consumption and component durability is necessary for optimal design. The findings of this study provide practical design insights for a more efficient multistage hydrogen compression system, aiming to reduce energy consumption while enhancing operational efficiency, reliability, and the overall economic feasibility of hydrogen charging infrastructure for hydrogen mobility.