基于混合子结构方法的充气膜结构气动特性

Aerodynamic characteristics of air-inflated membrane structure based on a hybrid substructure method

为了提高单纯依靠数值模拟方法求解膜结构气动参数的准确性,采用现场监测和CFD数值模拟相结合的混合子结构方法对国家游泳中心(水立方)屋盖ETFE充气膜结构的气动特性进行研究.首先分别设立ETFE充气膜结构和流场两个子结构,然后利用已建立的风荷载监测子系统和膜结构振动监测子系统所获得的数据作为CFD数值模拟的输入,进行绕流场分析,从而获得ETFE充气气枕的附加质量、气动力系数和气动阻尼等气动参数,并分析其随时间和风速的变化规律.分析结果表明,混合子结构方法是获得充气膜结构气动特性的一条有效途径.

To improve the accuracy of aerodynamic parameters of membrane structures depending on numerical simulation method,the aerodynamic characteristic of ETFE air-inflated membrane structure on the roof of the National Aquatics Center（NAC） is analyzed based on the hybrid substructure method of on-site monitoring and CFD numerical simulation in this paper.The ETFE air-inflated membrane structure and flow field are considered as two substructures,the vibration response of the ETFE air-inflated membrane structure is measured from the Health Monitoring System of NAC and treated as the moving boundary condition of air-inflated membrane structure in the flow field.Only the flow field around the moving boundary is simulated by the CFD code CFX 11.0.By CFD numerical simulation,the additional mass,aerodynamic damping and aerodynamic force of ETFE are obtained and the changing laws of these aerodynamic parameters with time and wind speed are studied.The research results indicate that the hybrid substructure method of on-site monitoring and CFD numerical simulation is an effective approach to obtain aerodynamic characteristics of air-inflated membrane structure.