Additional Wind Tunnel data for the transonic LK6E2 Missile Airframe

Abstract

This article is a discussion of the results of various measurement methods used in wind tunnel experiments on the generic transonic missile DLR-LK6E2. In addition to aerodynamic coefficients, the surface pressure distribution with pressure sensitive paint (PSP), the wall shear stress lines with the oil film interferometry (OFI) and the velocity field in cross sections with particle image velocimetry (PIV) were determined. The optical measurement techniques have been carried out for a wide range of total incidences for a transonic Mach number of 0.85 and a fixed roll angle of 45deg. The analysis of the data shows that at higher total incidences between of 15deg and 17.5deg the vortex system on the wings changes significantly. This change does not occur simultaneously on all wings, but with an offset with respect to the total incidence. The above conclusion is based on the evaluation of the PSP data and the OFI data. The two measurement methods complement each other in a very useful way. Due to strong reflections of the Laser light sheet on the curved fuselage, it was not possible to visualize the vortices in the area of the wing surface with PIV. Nonetheless, PIV provided useful data, e.g. on the behaviour of the leeward vortices originating at the nose.