| Counter flow thrust vectoring was successfully applied to a real engine for the first time.; The study begins with a characterization of the jet supplied by the engine, with a rectangular nozzle with an aspect ratio of 2. For 80,000 RPM , a detailed characterization of the free jet flow field is presented. Results include Schlieren visualization and PIV measurements in both centerline streamwise planes. The jet potential core was seen to be 2.5 nozzle heights and an asymmetry in the flow was observed in both planes. The jet is fully turbulent from the nozzle exit.; Counter flow thrust vectoring tests were conducted, in the early stage of the investigation, for gap heights ranging from 0.25 to 0.75 nozzle heights. The database thus obtained served as a guideline to choose the gap corresponding to G/h = 0.625 for detailed analysis of the flow field. Vectoring angles higher than 30 degrees, without jet attachment, were observed. Thrust losses were less than 8%.; For the selected gap, Schlieren visualization and PIV measurements were performed for two different configurations: with and without side plates covering the sides of the collar. Increased vectoring proved to decrease the jet's potential core and increase the thickness of the shear layers. It also increased the turbulence intensities in the collar region. The removal of the side plates prevented attachment, decreased the maximum vectoring angle and increased the secondary flow requirements. |
