TURBULENT MEAN-FLOW MEASUREMENTS IN A 2-DIMENSIONAL SUPERSONIC WAKE

Mean-flow measurements have been made in the supersonic wake of a very slender, two-dimensional body at zero incidence and heat transfer rate. Excellent correlation of the lateral distribution of axial velocity is obtained when the lateral distance is divided by the transverse wake scale which is formed from the measured velocity defect. The latter is found to decay as the inverse square root of distance for the entire range of about 1850 virtual model thicknesses mapped; thus, the transverse scale increases as the square root of distance. In the latter half of this range the lateral distribution of static temperature also appears to correlate in the same lateral coordinate, and the temperature defect also decays as the inverse square root of distance. It is demonstrated that these results are accurately predictable from a basic similarity analysis beginning with Townsend's measured velocity decay on the axis; the turbulent Reynolds number of 13.0 agrees closely with Townsend's 12.5. The corresponding Prandtl number found lies in the range from 0.65 to 0.70.