Effect of high negative incidence on the performance of a centrifugal compressor stage with conventional vaned diffusers

• Published in: Journal of thermal science 2011-06, Vol.20 (2), p.97-105
• Main Authors: Jaatinen, Ahti, Grönman, Aki, Turunen-Saaresti, Teemu, Backman, Jari
• Format: Article
• Language: English
• Subjects: Classical and Continuum Physics; Engineering Fluid Dynamics; Engineering Thermodynamics; Heat and Mass Transfer; Physics; Physics and Astronomy; 发病率; 叶片扩压器; 扩散器; 旋转速度; 离心压缩机; 级性能; 设计工作; 质量流量
• ISSN: 1003-2169; 1993-033X
• DOI: 10.1007/s11630-011-0442-0

Three vaned diffusers, designed to have high negative incidence （-8°） at the design operating point, are studied experimentally. The overall performance （efficiency and pressure ratio） are measured at three rotational speeds, and flow angles before and after the diffuser are measured at the design rotational speed and with three mass flow rates. The results are compared to corresponding results of the original vaneless diffuser design. Attention is paid to the performance at lower mass flows than the design mass flow. The results show that it is possible to improve the performance at mass flows lower than the design mass flow with a vaned diffuser designed with high negative incidence. However, with the vaned diffusers, the compressor still stalls at higher mass flow rates than with the vaneless one. The flow angle distributions after the diffuser are more uniform with the vaned diffusers.