Some Effects of Jet-Compressor Geometry on Efficiency: Compression-Ratio Curves with Two Maxima

摘要

Measurements were made with a new jet compressor of different geometry, and were compared with previous results. Efficiencies, compression ratios, and other data are presented for 5 systems of gases (He: Freon-113, He:CO2, air: Freon12, air: air, and Freon-12: air). Calculations of momentumflux balance within the mixing tube were made, and various results presented in a previous report are confirmed. Frictional losses in the mixing tube are shown for two different apparatuses, under several different operating conditions. The existence of two maxima in many of the curves of compression ratio versus outlet pressure is pointed out, and possible causes are discussed. A suggested cause of the second maximum is a rapid reduction shock loss in the driving stream, as the acceleration of this stream to a relatively high supersonic velocity is suppressed. (Author)