Study on Wind Pressure Characteristics of Low-rise Gable-roof Buildings Under Downburst

To study the downburst impact on low-rise gable-roof buildings,the wind pressure of low-rise gable-roof buildings under downburst was simulated based on computational fluid dynamics,and the effects of two typical roof slope angles and turbulence models on wind pressure characteristics of low-rise gable-roof buildings were analyzed.The results indicate that the negative pressure gradient on the upper edge of the windward surface is relatively higher and the roofs on both sides are subjected to negative pressure when the slope angle is small (16°).When the slope angle is large(35°),the negative pressure at the roof ridge is relatively larger and more concentrated while the roofs close to the windward side and the leeward side are subjected to positive pressure and negative pressure respectively;When the standard wall function is used to process the viscous influence area of the near wall,the differences of the wind pressure distribution of low-rise gable-roof buildings obtained by different turbulence models are mainly reflected in the windward surface,the roof ridge and near the upper and lower edges of the roofs on both sides.Shear stress transport turbulence model is more suitable for simulating the wind pressure at the ridge of low-rise gable-roof building with large slope angle under downburst,and dealing with the strong separation flow at the corners of the upper and lower edges of the roofs of low-rise gable-roof building with small slope angle along the direction of incoming flow.