Two-Dimensional Cascade Tests of MCA Blades in the High Transonic Mach Number Region. 5th Report. Effect of Space/Chord Ratio on the Parameters of Cascade Performance. (2).

Abstract

We carried out 2-D cascade tests of multiple-circular-arc (MCA) blades with a relatively high camber angle of 56 deg. in the region of inlet Mach number (M1) 0.4≤M1≤1.2, and with systematic variations of cascade geometry and incidence angle. Systematic data with respect to inlet Mach number characteristics of the cascade of MCA blades were obtained. We discsussed the effect of space/chord ratio on the performance of cascade of MCA blades, i. e. inlet Mach number characteristics, the relationship between incidence angle and parameters of cascade performance (incidence angle characteristics), in the constant stagger angle of 10°in the 4th report. In the present report, the following items are discussed on the basis of experimental results in the constant stagger angle of 5deg : 1. the effect of space/chord ratio on inlet Mach number characteristics ; 2. the effect of space/chord ratio on the relationship between incidence angle and parameters of cascade performance (incidence angle characteristics) at M1=0.9, 1.0, 1.1 ; 3. the effect of space/chord ratio on stall incidence angle, and reference incidence angle ; 4. the relationship between incidence angle and critical inlet Mach number in the set of space/chomd ratio of 0.4, 0.6, 0.8 ; 5. the optimal incidence angle and the effective working range of incidence angle which was deduced from the above mentioned relationship of (4) ; 6. relationship between space/chord ratio and deviation angle at optimal incidence angle.