Some tests on high-reaction compressor blading

Abstract

Two sets of blading, designed for 120 per cent reaction, and for flow coefficients of 0.667 and 1.0 respectively, have been tested in the N.G.T.E. low-speed compressor No. 106. The performances were compared with those of corresponding sets of 50-per-cent-reaction blading and with predictions based on simple theoretical methods. The high-reaction bladings both gave efficiencies which were lower by amounts broadly in line with the predictions. The work-done factors were also appreciably lower. The lower-flow-coefficient blading showed a significant advantage in pressure rise over its 50-per-cent-reaction counterpart, with about the same surge flow, while the high-flow blading was deficient in pressure rise but had a considerably wider surge margin. Both bladings might thus be of value in specialised situations where efficiency is not a prime consideration.