Comparison of Two Diffusers in a Transonic Centrifugal Compressor. (2003)

• Record Type: Journal Article
• Authors: Nakagawa, Koji; Hayami, Hiroshi; Keimi, Yuichi
• Is Part Of: International journal of rotating machinery. Volume 9:Number 4(2003)
• Page Start: 279
• Page End: 284
• Publication Date: 2003
• Subjects: Machinery -- Periodicals; Rotary combustion engines -- Periodicals; Turbines -- Periodicals; Hydraulic machinery -- Periodicals; 621.82
• DOI: 10.1155/S1023621X03000253
• Languages: English
• ISSNs: 1023-621X

Abstract

Abstract : Flow mechanisms suppressing the flow separation in two diffusers, a low-solidity cascade diffuser and a vaned diffuser with additional small vanes near the inlet, were compared mainly by numerical simulation. As the superiority of the low-solidity cascade diffuser was expected, a series of experiments was conducted using a transonic centrifugal compressor with a maximum pressure ratio of 7. The performance of the compressor with the vaned diffuser was comparable to that of the low-solidity cascade diffuser only between the surge point and the design flowrate at a pressure ratio of 3.5. The maximum flowrate of the vaned diffuser was lower than that of the low-solidity cascade diffuser. At higher rotational speeds, the pressure ratio at the surge point, the efficiency, and the flow range of the low-solidity cascade diffuser exceded those of a vaned diffuser at a pressure ratio of 3.5.