钝体结构倒U形梁气动特性试验和数值研究

Aerodynamic Characteristic Investigation of a Blunt Body Structure Named Inverse-U Shaped Beam with Wind Tunnel Tests and Numerical Simulations

为了探索有效的钝体结构气动特性三维数值分析方法,对钝体结构倒U形梁的气动特性进行了风洞试验和数值模拟研究.通过风洞试验得到与结构气动特性相关的气动力系数和颤振导数.利用二维或三维模型分别对结构的气动特性进行了数值模拟研究,并计算了相关的气动参数.计算过程中基于分块迭代耦合方法考虑流体-固体耦合效应,利用自编程序结合CFX软件实现不同物理场间的数据交换和传递,采用快速有效的网格移动控制算法处理移动边界问题.风洞试验测量和数值计算中均考虑了湍流效应,其中数值计算应用了k-ω剪切应力输运模型和分离涡模型.通过风洞试验测量与数值模拟研究可以发现,钝体结构倒U形梁的气动稳定性较差.对气动参数的计算结果表明,本文的三维数值计算方法可以有效地获取钝体结构的气动参数,在风工程领域具有重要应用价值.

The aerodynamic characteristic of a blunt body structure named inverse-U shaped beam is investigated with both wind tunnel tests and numerical simulations in order to find an effective three dimensional numerical method. The wind tunnel test was designed and made to measure its aerodynamic force coefficients and flutter derivatives. Then both two dimensional and three dimensional numerical methods were used to investigate its aerodynamic characteristics. The fluid-structure interaction effect was simulated based on a block-iterative coupling method during the simulation process, and data exchange and transfer were achieved with self-developed program combined with CFX software. Also, an efficient mesh control method was taken to solve moving boundary problems. Turbulence flow effect is included by both wind tunnel test and numerical simulations,where k-ω SST turbulent model and DES turbulent model were applied. Both experiment and simulations show that the inverse-U shaped beam has poor aerodynamic stability. The computed results also show that the 3D numerical method presented can obtain aerodynamic parameters of blunt body structures with sharp edges effectively, which has significant potential in wind engineering applications.