基于WOA-GRNN代理模型的Π形截面梁风嘴气动外形优化  

Aerodynamic Shape Optimization of Π-Shaped Composite Bridge Deck with Wind Fairing Based on WOA-GRNN Surrogate Model

作　　者：刘汉云 陈柏翔 韩艳 胡朋 蔡春声 王力东 LIU Han-yun;CHEN Bai-xiang;HAN Yan;HU Peng;CAI C S;WANG Li-dong(School of Civil Engineering,Changsha University of Science&Technology,Changsha 410114,Hunan,China)

机构地区：[1]长沙理工大学土木工程学院,湖南长沙410114

出　　处：《中国公路学报》2023年第8期76-86,共11页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(52108433,52178452,52178451,52178450);湖南省领军人才项目(2021RC4031);湖南省自然科学基金项目(2021JJ40587);湖南省科技厅优秀青年项目(21B0309);高速铁路建造技术国家工程研究中心开放基金项目(HSR202004);湖南省研究生科研创新项目(CX20220889)。

摘　　要：Π形截面大跨度桥梁极易发生涡激振动,工程中常通过增设风嘴进行抑振,然而风嘴参数选择及抑振效果高度依赖经验或枚举试算,效率低下。为此,基于WOA-GRNN代理模型对Π形截面梁在多参数设计空间内的气动外形优化问题进行了研究。首先,选取风嘴长度、纵深和风攻角,构成多参数设计空间;其次,采用最优拉丁超立方抽样和Sculptor?网格变形驱动技术获取设计空间初始代表点集及其高质量计算网格,通过CFD数值模拟获得训练数据池;然后,建立风嘴设计参数和桥梁涡振响应的WOA-GRNN代理模型,通过数据池训练模型;接着,以某典型Π形截面大跨桥梁为工程背景,利用训练后WOA-GRNN代理模型预测多参数设计空间内的桥梁涡振响应面,通过自适应差分进化算法全域寻优,获得了最优设计参数及涡振响应值;最后,通过风洞试验结果对比验证了所提方法的正确性。研究结果表明:WOA-GRNN代理模型可显著提高桥梁气动外形优化效率;对案例Π形截面梁,最优风嘴气动外形#1的竖弯涡振响应相较于原型断面降低99%,抑振效果极佳。研究成果可为今后同类型Π形截面梁的涡振控制、气动外形优化以及相关研究提供重要参考。Long-span bridges withΠ-shaped cross-sections are highly susceptible to vortex vibrations.Wind fairings are often used in engineering to suppress vortex-induced vibrations(VIVs).However,the selection of a wind fairing able to provide excellent vibration suppression is highly dependent on experience or enumeration,making this process time-consuming.To address the issue,this study investigated aΠ-shaped girder in a multi-parameter design space based on a whale optimization algorithm-general regression neural network(WOA-GRNN)surrogate model.First,the length and height of the wind fairing and attack angle of the wind were selected to form a multi-parameter design space.Afterwards,an optimal Latin hypercube sampling method and Sculptor®software with mesh deformation drive technology were used to obtain an initial set of representative points in the design space.The training data pool was obtained via a computational fluid dynamics(CFD)-based numerical simulation.Then,a WOA-GRNN surrogate model related to the design parameters of the wind fairing and vortex vibration response was developed and trained through the obtained CFD data pool.Next,a typical long-span bridge withΠ-shaped girder was used as the engineering background to predict the VIV response surface of the bridge in the multi-parameter design space using the trained WOA-GRNN surrogate model.Finally,the correctness of the surrogate model was verified by comparison with wind tunnel test results.The results show that the WOA-GRNN surrogate model can significantly improve the efficiency of bridge aerodynamic shape optimization.For theΠ-shaped beam in the studied case,the vertical VIV response of the optimal wind fairing aerodynamic shape#1 is 99%lower than that of the prototype section;in addition,the VIV suppression effect is excellent.This study can provide important references for future VIV control,aerodynamic shape optimization,and related research on the same type ofΠ-shaped girder.

关 键 词：桥梁工程 气动外形优化 代理模型 风嘴 Π形截面梁 涡激振动 

分 类 号：U443.5[建筑科学—桥梁与隧道工程]