Affiliation:
1. Department of Mechanical Engineering, University of Sheffield
Abstract
The trends in fluid mechanical development of centrifugal compressors are discussed. The main developments in the impeller are the application of quasi-three-dimensional isentropic methods together with some separation criteria based on two-dimensional turbulent boundary layer theory. Diffusers are sometimes designed on a simplified two-dimensional basis but channel diffusers still appear to be preferred especially at high Mach numbers. Recent visualization studies have shown how far the actual flow in impellers may depart from the actual model and there is a lack of systematic quantitative experimental work on limiting blade loading and pressure gradients both in impellers and diffusers. A summary of gas turbine centrifugal compressors is also made.