摘要：

A wind-tunnel investigation of buffeting on the vertical fin of a rigid 6% model of the F/A-18 has been conducted in the Institute for Aerospace Research 5 × 5-ft Trisonic Blowdown Tunnel. Unsteady pressure measurements on the vertical fin were made by means of 24 fast response transducers on each surface. The vortex flow structure behind the fin was studied with the aid of a 49 pressure-sensor rake mounted on the model sting. In addition to measuring steady pilot pressure values to deduce pressure contours, unsteady pressure signals were obtained from 13 fast response transducers. Spectral analyses of the pressure fluctuations on the fin and in the vortical flow region behind the fin were performed to detect the presence of dominant oscillations during buffeting. The leading-edge extension was instrumented with pressure orifices and fast response transducers to study the flowfield beneath the roll-up vortex. The test was carried out with leading-edge extension fences on and off to note their effect on tail buffet loads.

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