Near-wake measurements of a delta wing in a supersonic stream

The near-wake region of a 75-deg sweptback delta wing was studied experimen tally in a Mach 2.49 stream. Five-hole conical probe measurements were cond ucted vertically and horizontally through the primary vortices at the trail ing edge and half-chord downstream of the planform for 7- and 12-deg angles of attack. The Mach number and pressure distribution profiles are summariz ed, and comparisons of how properties at different survey stations are pres ented. A novel calibration approach using a three-dimensional Navier-Stokes solver to generate numerically the calibration data for a blunt-nosed five -hole conical probe over a range of Mach numbers and pitch angles was emplo yed. The magnitude of the pitot, total, and static pressure deficits in the wake region increased with increasing angle of attack for the same measure ment plane and decreased with the downstream distance. The swirl profiles h ave supersonic and high transonic peak magnitudes, and estimated core dimen sions suggest vortex stretching in the vertical direction and convection do wnstream. A decrease in the radial Mach number component confirms the vorte x trajectory changes from a strong downward how over the planform to a grad ual return toward the freestream in the near wake. Unlike the experimental results from transonic and low-speed leading-edge vortices, the axial and t otal Mach number distributions in supersonic vortices are found to be wakel ike.