Optimization of Suction Channel for Improving Performance of Process Centrifugal Compressor

Design parameters for a suction channel of process centrifugal compressors were investigated, and an optimizing method to improve efficiency by using the new design parameters was proposed. Both pressure loss and circumferential flow distortion in the suction channel were evaluated by using computational fluid dynamics. The passage sectional area ratios Ac/Ae, Ae/As, and Ac/As were found to be the dominant parameters for the pressure loss and circumferential flow distortion, where Ac, Ae and As are passage sectional areas for the casing upstream side, casing entrance and impeller eye, respectively. The shape of the suction channel was optimized by using the new design parameters. In order to evaluate improvement effect of this optimizing method on stage efficiency, base and optimized types were manufactured and tested. Test results showed that the optimized suction channel achieved 3.8％ higher stage efficiency than the base one while maintaining the operating range.