Wind tunnel measurements of cavity pressure dynamics in a low-rise flexible roofed building

Results are presented from a series of wind tunnel tests to measure the cav ity pressure dynamics of a flexible roofed building with a single dominant opening. Tests were conducted in a simulated atmospheric boundary layer, re presentative of an open-country terrain, for the model configured with five different roof tensions, three internal volumes, two windspeeds and five o pening azimuth angles. The ratio of air-to-building bulk moduli was used as a measure of roof tension and buildings with 0.02 < K-a/K-b < 7.5 were tes ted. It was found that the cavity scaling parameter (Eq. (1)) provided a co nvenient means of collapsing the unsteady cavity pressure data for those co nfigurations where significant resonance occurred. A flow component into th e opening was necessary to sustain large resonant oscillations and this occ urred with an opening on both windward and leeward sides of the building. I ncreased flexibility of the roof membrane reduced the value of the Helmholt z frequency and also reduced the magnitude of the resonant response. (C) 19 99 Elsevier Science Ltd. All rights reserved.