考虑流固耦合作用的充气膜结构风压分布研究

充气膜结构是典型的风敏感型柔性结构,风荷载经常起关键的控制作用。本文利用ANSYS14.5程序中的workbench平台,考虑流固耦合作用,研究矩形平面气承式充气膜结构的风压系数分布。其中,选用基于雷诺时均模拟法的RNGk-ε湍流模型进行风场模拟,采用弱耦合分析方法模拟流固耦合风荷载效应。分析的参数选择风向角、结构内压、矢跨比和平面长宽比。针对矢跨比分别为1/4,1/3和1/2,长宽比分别为5/3,2/1和3/1的柔性充气膜结构模型,计算不同内压及不同风向角作用下的结构响应。结果表明,考虑流固耦合作用时,充气膜结构的风压体型系数比不考虑流固耦合作用的刚性模型明显偏大,其影响因子在1.25~1.5之间;充气膜结构的风压系数分布受风向角、内压、长宽比及矢跨比的影响较大。

On wind pressure coefficient distribution of air-supported structures considering fluid-structure coupling

Air-supported structures are typical flexible structures ,which are sensitive to wind .Wind loads are often crucial to structural design .The workbench platform in ANSYS14 .5 program was used to investigate the wind pressure coefficient distribution of rectangular plane air-support structure considering fluid-structure coupling effect .RNG k-εturbulent model based on Reynolds averaged N-S equation was used to simulate the wind field while the weak coupling method was adapted to investigate the coupling effect .The rise-span ratio of 1/4 ,1/2 ,1/3 and length-width ratio of 5/3 ,2/1 ,3/1 were adopted to calculate the structural response under different inner pressure and wind direction angles . Results show that the coefficient of wind pressure on structure considering fluid-structure coupling effect differs significantly from that without considering fluid-structure coupling effect and the impact index is between 1 .25~1 .5 .The wind pressure coefficient distribution of structure is influenced by the wind angle ,inner pressure ,length-width ratio and other factors such as the rise-span ratio .