An example of cavity resonance in a ground-based structure

This paper describes the occurrence of shear-layer-induced cavity oscillations in a 1:100-scale, wind tunnel model of a ground-based, 51-m-diameter optical telescope enclosure. The enclosure is 3 4 -spherical in shape, where the lower one-quarter of the sphere is removed to provide a flat base. The enclosure opening through which the telescope looks is 24 m in diameter. Four shear-layer modes were observed to excite pressure pulsations in the enclosure at Strouhal numbers having multiples of 0.5 over a range of Reynolds numbers of 2.8×105⩽ Re ⩽1.40×106.