AERODYNAMIC PERFORMANCE OF AXIAL-FLOW FAN STAGE OPERATED AT NINE INLET GUIDE VANE ANGLES

摘要

The overall performance of a fan stage with nine inlet-guide-vane angle settings is presented. These data were obtained over the stable flow range at speeds from 60 to 120 percent of design for vane setting angles from -25° to 42. 5°. At design speed and design inlet guide vane angle, the stage had a peak efficiency of 0. 892 at a pressure ratio of 1.322 and a flow of 25. 31 kilograms per second. The stall margin based on peak efficiency and stall was 20 percent. Based on an operating line passing through the peak efficiency point at the design setting angle, the useful operating range of the stage at design speed is limited by stall at the positive setting angles and by choke at the negative angles. At design speed the calculated static thrust along the operating line varied from 68 to 114 percent of that obtained at design setting angle.