大跨屋盖风压分布的数值模拟及拟合方法研究

针对大跨度屋盖结构绕流特性较为复杂的问题,借助CFD数值模拟技术对大跨度屋盖表面风压分布进行了数值模拟,采用了雷诺应力湍流模型(RSM)和SIMPLE压力校正算法,并与风洞试验结果进行了对比分析,两者吻合较好.为了便于工程设计,提出了风压分布的二维几何平面拟合方法及拟合公式及同时考虑风向角的三维拟合方法及公式.结合CFD数值模拟结果对平均风压系数进行了拟合,阐述了风压系数拟合方法的准确性及拟合中应注意的问题.

Numerical simulation of wind pressure distribution on long-span roofs and curve fitting method

Wind nearby long-span roofs are involved in many physical phenomena such as impingement,separation,reattachment,circulation and vortices and the wind pressure distribution is complicated.Numerical simulation of wind-induced pressure has been performed on long-span roofs by means of computational fluid dynamics method.The simulation is based upon the Reynolds-averaged equations,in which Reynolds stress equation model(RSM) and SIMPLE technology are used.Compared with wind tunnel tests,the computational results have good agreement with the experimental data.For the convenience of design,two-dimension curve fitting formula is presented.Furthermore,three-dimension curve fitting formula considering wind direction is presented too.Using the CFD results mentioned above,the curve fitting of wind pressure coefficient is performed on long-span roof and the veracity of the curve fitting method and the existent problem are discussed in this paper too.