Density and Temperature Distributions in Hypersonic Sphere Wakes

The radial and axial dependence of the mass density distributions in both the laminar and turbulent wakes of 1.0 and 2.7 in. diameter spheres flown at Mach 13.5 in nitrogen atmospheres have been determined using the electron beam fluorescence probe technique. The distribution of temperature in the wake has also been inferred by invoking the assumption that the wake is isobaric. Both the distribution of mass and the distribution of temperature in the wake may be characterized by the behavior of 2 parameters: the amplitude of the mass density or temperature on the center line of the wake and the corresponding profile width. Experimental data are presented for these parameters.