Optimal r/b ratio of bend channel in centrifugal compressor

Suping Wen1, Xiaowen Hu1, Yong Zhang2, Jun Wang2, Tingbin Li1
1School of Energy and Power Engineering, Xi’an Jiaotong University, Xi’an, China
2Shenyang Blower Works, Shenyang, China

Tóm tắt

A numerical investigation on the flow in a bend channel by coupling the impellerwith the vaneless diffuser in a centrifugal compressor with different r/b ratios (bend radius r to bend channel width b) is presented. The jet-wake effect of the impeller outlet is considered and flow pattern in the bend channel and the performance of the centrifugal compressor stage are investigated. The results indicate that there is an optimal r/b ratio for increasing the stage efficiency to the highest for a specific compressor stage. The change in r/b ratio significantly affects the flow angle of the bend channel outlet. The prime reason for the total pressure loss in the bend channel is the wall friction in the bend channel.

Tài liệu tham khảo

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