Experimental Investigation of Turbojet Thrust Augmentation Using an Ejector

In recent years a significant number of commercially available small turbines have become available. At the same time unmanned aerial vehicles and smart munitions have decreased in size while their endurance needs have increased. With these new platform requirements comes the need for a propulsion system with reliability, good endurance and low acoustic signature. There has been much research accomplished in the area of steady cold flow primary sources, but little experimental work has been done using a gas turbine as a steady flow hot source. This investigation concerns the performance of an ejector driven by a small gas turbine. Aircraft applicability was a deciding factor in test geometry. Varying both engine throttle and the ejector's downstream distance resulted in peak augmentation values of nearly 1.4.