Measurements of supersonic wing tip vortices

An experimental study of supersonic wing tip vortices has been conducted at Mach 2.49 using small-scale four-hole and five-hole conical probes, The study was performed 2.25 chords downstream of a semispan rectangular wing at angles of attack of 5.7 and 10.4 deg. The main objective of the experiments was to determine the Mach number, flow angularity and total pressure distribution in the core region of supersonic wing tip vortices. A secondary aim was to demonstrate the feasibility of calibrating a conical probe using a computational solution to predict the flow characteristics. Results of the present investigation showed that the numerically generated calibration data can be used for pointed nose four-hole conical probes but were not sufficiently accurate for conventional five-hole probes due to nose bluntness effects. A combination of four-hole conical probe measurements with independent pitot pressure measurements indicated a significant Mach number and total pressure deficit in the core regions of supersonic wing tip vortices, combined with an asymmetric ''Burger-like'' swirl distribution.