This paper contains some peak-performance criteria, based predominantly upon test data, which account for the effects of almost all of the significant design variables on the practical over-all performance of carefully designed centrifugal-compressor stages (having vaneless diffusers, wellmatched return channels or volutes, and no inlet prerotation). This information is expected to allow a designer to take advantage of the best possible performance history of the past in creating successful

more »

... -cost" centrifugal-stage designs for any application. Utilization of the basic material described in this paper is qualified by the presentation of performance correlations for the stages of two different centrifugal refrigeration compressors, each of which was operated with air and with its design refrigerant vapor. In this portion of the study, it is demonstrated that successful correlations of centrifugal compressor-stage performance can be accomplished, even though the test and design vapors produce considerably diverse conditions of rotational Mach number and specific-heat ratio. These correlations include not only the peak-performance parameters, but the basic shapes of the characteristic curves as well.