带悬挑女儿墙双坡屋面风压的数值模拟分析

Numerical Simulation of Wind Pressures on the Gable Roof with Cantilevered Parapets

考虑加设悬挑女儿墙对双坡屋面风压的影响,将悬挑女儿墙设置高度与房屋檐高的比值作为控制参数,利用计算流体力学软件CFX 10.0,以及SSTk-ω模型和混合网格对一典型低矮双坡门刚厂房屋面平均风压进行数值模拟.分析悬挑女儿墙对屋面风压的影响,优化设计参数.采用计算流体动力学数值模拟方法,探讨常见的双坡屋面轻钢厂房模型在增设悬挑女儿墙后,其屋面风压的变化及影响,并与未增设悬挑女儿墙时的风洞实验结果对比.结果表明,增设悬挑女儿墙后能明显地降低屋面风荷载敏感区的负压峰值及风荷载体型系数.

Considering the influence of wind pressure on the gable roof with cantilevered parapets, and taking the ratio of the height of cantilevered parapet to the height of eave as the control parameter, the average wind pressure on the gable roof of a typical low-rise portal steel frame is simulated numerically by the computational fluid dynamics software CFX 10.0, SST κ-ω model and mixed grid, the influence of the cantilevered parapets on the wind pressure is analyzed, the design parameters are also optimized. When adding the cantilevered parapets, the changes and effects of the wind pressure on gable roof of the common light-weight steel building, are discussed by numerical simulation, the calculation results are compared to the experimental wind tunnel results without parapets. The comparison shows that the cantilevered parapets can obviously reduce the peak values of negative pressure on the zones susceptible to wind pressure, and the shape factor of wind load.