Performance and wall static pressure measurements on centrifugal compressor diffusers

TLDR: In this article, the results of experimental studies on performance and wall static pressure distribution in the diffuser passage of a low specie c speed centrifugal compressor are given, and the performance tests were carried out with vaneless, vane and low-solidity vane diffusers at speeds of 2500, 3000 and 3500r/min.

Abstract: The results of experimental studies on performance and wall static pressure distribution in the diffuser passage of a low specie c speed centrifugal compressor are given. The performance tests were carried out with vaneless, vane and low-solidity vane diffusers at speeds of 2500, 3000 and 3500r/min. Diffuser wall static pressures measured at 3000r/min for four e ow coefe cients on the shroud and hub walls are reported. The peak energy coefe cient is maximum for the vane diffuser. The operating range of the low-solidity vane diffuser is wider than that of the vane diffuser. At high e ow coefe cients, the static pressure rise is substantially lower for the vane diffuser, as the incidence on the vane leading edge is very high. The low- solidity vane diffuser did not suffer a large drop in static pressure near the leading edge. The most probable reason may be the large area available in the low-solidity vane diffuser for e ow adjustment and weaker e ow separation zones on account of the lower number of vanes.