中文摘要：

对低层四坡屋面房屋模型进行了风洞试验，给出了屋面平均和脉动风压系数等值线和各面体型系数的变化规律。采用计算流体力学软件FLUENT，对大气边界层中的试验模型进行了三维定常风场的数值模拟，并将数值模拟结果与试验结果进行了比较分析，变化规律吻合较好。在此基础上，深入研究了不同风向角下房屋屋面坡度、挑檐长度、檐口高度和长宽比对低层四坡屋面平均风压系数及各面体型系数的影响，并提出了各面体型系数的建议取值。研究结果表明：数值风洞能够较好地反映低层四坡屋面房屋的风荷载特性；各参数对屋面风压系数的影响程度各异，与风向角密切相关；屋面坡度对屋面风压分布和大小有明显的影响；四坡屋面屋脊背后容易形成较高的局部负压区域；当屋面坡度小于35°时，四坡屋面房屋迎风屋面的体型系数绝对值大于相应双坡屋面房屋。该结论和提出的体型系数建议取值为低层四坡屋面房屋的工程抗风设计提供了可靠依据。

英文摘要：

Wind tunnel tests on wind load characteristic of low-rise hip roof buildings were presented. The change laws of isolines of mean and fluctuating wind pressure coefficients of roof and shape coefficients of each face were obtained. The computational fluid dynamics software FLUENT was employed to numerically simulate the 3D steady wind flow field around test model in atmospheric boundary layer, and the numerical simulation results agreed well with the test results. Then a detailed parametric study was performed for mean wind pressure coefficients and shape coefficients of low-rise hip roof buildings under different wind direction. The parameters included roof grade, cave length, cave height and length-width ratio. The study results show that the numerical simulation is a feasible way to study wind load characteristic on low-rise hip roof buildings. The influence levels of different parameters on the wind pressure coefficient of roof are also affected by wind direction. Roof grades show more influence on both distribution and magnitude of wind pressure on hip roof. Higher negative pressure zone will be formed behind roof rigging of hip roof buildings. The absolute value of shape coefficient of windward roof of hip roof buildings is bigger than that of gable roof buildings when the roof grade is less than 35°. The shape coefficients which are obtained accordin engineering wind resistance design of low-rise g to the study results provide a foundation for the roof buildings.