21st Congress of International Council of the Aeronautical Sciences, Melbourne, Australia, 13-18 September, 1998
Paper ICAS-98-3.2.3

A STUDY OF VORTEX BREAKDOWN ON PITCHING DELTA WINGS USING HIGH RESOLUTION PRESSURE MEASUREMENTS

Jupp M. L., Coton F. N., Green R. B., Galbraith R. A. Mc D.
University of Glasgow, United Kingdom

Keywords: vortex breakdown, pitching delta wings, high resolution pressure measurements

This paper describes and presents results from wind tunnel tests conducted on two 60° delta wings at a root chord Reynolds number of 2.7 x 10^6 . In these tests, the wings were instrumented with 192 miniature pressure transducers which, in conjunction with a powerful multi-channel data-logging system, allowed the distribution of time-varying surface pressures to be measured at high temporal resolution. The wings differed only in the shape of the nose section. It is shown that analysis of root-mean-square (RMS) pressure on the leeward surface of each wing highlights significant differences in the formation, position and movement of the vortical structures on the two planforms with increasing pitch rate. The relationship between these observations and previously observed behavioural characteristics of vortex breakdown is then discussed.

view full paper