Aerodynamic Design Improvement of Centrifugal Compressor for Turbocharger Application

Abstract This paper focuses on the design improvement of a baseline centrifugal compressor used in a turbocharger. Centrifugal compressors are favored for their compactness, high pressure ratio output, and wide operating range. The baseline compressor was initially tested and achieved 72% efficiency and 17% surge margin. However, scope for improvement of efficiency and choke mass flow was identified in the new design. Geometric modifications were made to geometric parameters such as impeller blade angle progressions, impeller sweep back angle, vane wrap angle, and impeller exit width. The volute cross-section area was also reduced to improve overall efficiency. Through these modifications, a 5% improvement in efficiency and 3% improvement in choke mass flow were achieved. The modified compressor, tested in a gas stand facility, demonstrated an efficiency of 77% compared to the baseline’s 72% efficiency. These results highlight the importance of geometric parameters in optimizing the performance of centrifugal compressors in turbocharger applications.