ANNULAR NOZZLE EJECTOR

Abstract : Work performed on the annular nozzle ejector is described. The full scale ejector assembly and associated equipment was fabricated. Tests indicated that its augmentation performance was approximately 5 points less than that of the small scale hardware. The jet wake data in combination with jet area distribution indicated the discrepancy between full scale and small scale results may have been caused by less effective ejector action due to the non- uniform momentum curtain. The ejector wake data indicates roughly an order of magnitude reduction in wake total pressure and temperature from the unaugmented turbojet. Ground effect tests were conducted with the small scale model. This model geometrically represents the full scale hardware. These tests indicated that an augmentation reduction of approximately 15 points could be anticipated at a ground clearance of 0.35 diameters. The decrease in performance began at approximately 1.3 diameters. Blockage f the secondary flow passages improved performance only below 0.10 diameters ground clearance. Above that level the best performance was obtained by permitting secondary pumping to continue.