Design and Analysis of Energy-Efficient Low-Flow Centrifugal Compressors

Abstract

With the increasing demands of energy-saving from industries, the low-flow coefficient and low specific speed centrifugal compressors have gained more attention. The design of this type of compressor faced many challenges, for example, high secondary flow losses, high tip leakage losses, and low exit width based on a Reynolds number. The design also lacks a reliable database for preliminary studies. The impeller design studies were limited. Most designs for low-flow coefficient and low specific speed compressor follow the traditional methods. This paper presents design studies and discusses some unique design features to improve performance of this type of compressor. The detail computational fluids dynamics (CFD) results are presented to demonstrate the success of the design strategies. A prototype compressor for fuel cell applications was built, and performance tests were performed. The test results are compared with those of the computational analysis, and the agreement is reasonably satisfactory. The compressor meets the customer's performance goals. The design features can be used for future low-flow coefficient and low specific speed centrifugal compressor design.