We examine flow and noise in a hydrogen compressor’s valve, jacket, and discharge pipe.
Abstract (original) · EN
To analyze the flow and noise characteristics of a positive displacement hydrogen compressor, a computational fluid dynamics (CFD) simulation based on the Lattice-Boltzmann Method (LBM) was performed. For detailed analysis the discharge flow of the compressor was divided into three regions: the area around the valve, the discharge jacket, and the outlet pipe. Hydrogen passing through the valve formed turbulent jets, which induced high-frequency noise. Inside the discharge jacket, changes in the cross-sectional area caused continuous variations in the average velocity and turbulence characteristics. In the outlet pipe with an elbow, high flow velocity corresponding to the relatively narrow cross-section was observed. Additionally, flow separation occurring on the inner corner of the elbow enhanced turbulence, contributing to the amplification of high-frequency noise. This study provides a physical understanding of the flow and noise issues in positive displacement hydrogen compressors and presents a fundamental analysis to support the design of efficient and low-noise compressors.
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