深圳平安国际金融大厦风致响应大涡模拟分析

Large eddy simulation of wind induced response on the Shenzhen Pingan IFC Building

运用一种新的湍流脉动流场产生方法模拟了三种风场的湍流边界条件,采用一种新的大涡模拟的亚格子模型,基于Linux系统下软件平台Fluent 6.3的并行计算技术,对深圳平安国际金融大厦进行了全尺寸、高雷诺数(高达10×108量级)的数值风洞模拟。计算了三种风场下建筑表面平均、脉动风压及风荷载时程数据。利用惯性风荷载(IWL)法得到三种风场下深圳平安金融大厦的基底等效静风荷载以及结构顶部峰值加速度响应。分析了不同的湍流来流对结构风压系数、风荷载及加速度响应的影响。分析结果表明:三种来流风场条件下,深圳平安金融大厦周围风场相差较大,来流的湍流强度越高,建筑物前方的脉动风速越高;顺风向等效风荷载主要受平均风速控制,横风向等效风荷载主要受脉动风控制;湍流强度越大,横风向等效风荷载越大;中国规范建议的湍流流场下,深圳平安金融大厦10年重现期顺风向、横风向峰值加速度响应满足居住者舒适度要求。

A new inflow turbulence generator was applied to simulate three kinds of inflow boundary conditions of turbulent flow field. A new one-equation dynamic subgrid scale （SGS） model was adopted for the present full-scale size large eddy simulations with extremely high Reynolds numbers （ 10 × 10^8 ）. The mean pressures, fluctuating pressures and time-histories of the wind forces on the surface of Shenzhen Pingan IFC in the three flow field conditions were calculated based upon the paralleled technology of Fluent 6.3 software platform under the Linux system. The equivalent static wind loads and wind-induced responses were obtained by the IWL method in frequency domain analysis. The effects of different turbulent flow fields on the wind pressure coefficients, wind forces and wlnd-induced response were discussed. The wind fields around the Shenzhen Pingan IFC are significantly different under the uniform and turbulence approaching wind flows. The along-wind loads are mainly dependent on the mean wind velocity. The across-wind loads increase with the increase of the turbulence intensity of approaching wind flow. In terms of the turbulence flow defined by Chinese code, the along and cross wind peak accelerations under 10 years return period at the top floor of the Shenzhen Pingan IFC satisfy the comfort requirement for the oecuoant.