Characterization of the three dimensional turbulent flow structure of angled injection into a supersonic cross flow
1996, American Institute of Aeronautics and Astronautics, Inc. An experimental analysis of the three-dimensional, turbulent, compressible flow structure of a highly underexpanded Mach 1.8 jet injected at an angle of 25 degrees into a Mach 2.9 free stream was performed. The experimental methods included cross-film anemometry, conventional mean flow probes (Pitot and cone-static pressure), schlieren photography and surface oil flow visualization. The mean flow data consisted of axial mass flux, y-z plane mass flux vector, and total pressure contour plots. Turbulence data included x, y and z mass flux turbulence intensity components, x-y and x-z Reynolds shear stresses, and anisotropy coefficients. Two relatively large recirculation cells were located just down stream of the injector. In addition, the vortex pair within the plume dramatically affected the overall mean and turbulent flow structure. The axial turbulence intensity was found to have two peaks that were co-located the vortex pair. The transverse and spanwise intensities were found to peak on the right and left sides of the plume, respectively. The anisotropy contours also showed a strong dependence on the secondary motion of the two counter rotating vortices. In particular, the z-y coefficient had a maximum located within one vortex, and a minimum in the other. The present data also suggested that the interaction between the vorticity and turbulent flow structure may have been responsible for the slight asymmetry noticeable in the present as well as numerous other studies.