- 期刊
Unsteady Diffuser Flow in a Transonic Centrifugal Compressor
摘要
The paper deals with the clarification of the unsteady, transonic flow phenomena occurring in the vaned diffuser area of a high pressure ratio centrifugal compressor stage. A description of the test rig, the measurement technique applied and a brief description of the steady 3D code used for the theoretical investigations are given. The measured stage characteristic and the mean diffuser pressure rise as deduced from the 3D calculations are presented. The unsteady flow character in the vaned diffuser region is experimentally resolved with the help of laser measurements performed for the whole diffuser region, from impeller exit up to the vaned diffuser exit. A comparison with the results of a steady state 3D calculation carried out separately for the rotor and diffuser shows good agreement with reality, especially with the flow in the rear part of the diffuser, where the real flow was found to be almost steady.