Research and Design of a Centrifugal Compressor for Fuel Cell Turbocharger

A low specific speed centrifugal compressor powered by an ordinary electric motor (20, 000 rpm) has been designed at Tsinghua University for air systems application of automotive fuel cell engines. Preliminary design characteristics have been concluded. Three-Dimensional Computational Fluid Dynamics (CFD) is used to investigate the flow field of the impeller. The characteristic curve and primary aerodynamic parameters of designed impeller are achieved. The experimental results indicate that the designed low specific speed centrifugal compressor has comparatively high efficiency and wide operating range. The highest efficiency and pressure ratio of the centrifugal compressor is up to 78% and 1.42, respectively. The designed low specific speed centrifugal compressor can meet the requirement of air systems of automotive fuel cell engines. Moreover, the low specific speed centrifugal compressor avoids difficulties of usage of high-speed electric motors in high specific speed compressor.