节段模型长宽比对风洞测力试验及计算分析的影响  

Influence of Length-width Ratio of Section Model on Wind Tunnel Test and Calculation Analysis

作　　者：白桦[1] 王涵 姬乃川 李加武[1] BAI Hua;WANG Han;JI Nai-chuan;LI Jia-wu(School of Highway,Chang’an University,Xi'an 710064,Shaanxi,China;Shaanxi Transportation Planning and Design Institute,Xi'an 710065,Shaanxi,China)

机构地区：[1]长安大学公路学院,陕西西安710064 [2]陕西省交通规划设计研究院,陕西西安710065

出　　处：《中国公路学报》2022年第8期202-212,共11页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(51978077);陕西省自然科学基础研究计划项目(2020JM-241)。

摘　　要：为提高风洞试验数据的可靠性、了解节段模型端部效应对试验结果的影响,通过风洞试验与数值模拟相结合的方法针对典型桥梁断面制作多组不同长宽比的节段模型研究了节段模型长宽比对三分力系数的影响。利用不同长宽比节段模型试验得到的三分力系数,分析三分力试验误差对静风稳定性及抖振响应的影响。为进一步扩大模型长宽比的研究范围,借助了CFD方法重现风洞试验,在保证数值模拟精度的前提下开展了多个长宽比模型的气动力与流场分析,系统总结不同长宽比模型端部效应的影响规律。分析结果表明:为保证测力试验结果的精度和稳定性,节段模型长宽比建议大于等于3,对于流线型箱梁断面,可以适当放宽要求,节段模型长宽比应大于等于2;当长宽比小于建议值,得到的静风稳定结果和抖振响应结果偏危险,长宽比越小,偏差越大;流线型箱梁阻力系数单侧“影响区”的量纲一的长度约1,升力矩系数单侧“影响区”量纲一的长度约为0.6,升力系数的单侧“影响区”量纲一的长度明显远大于其他气动力系数。流线型断面顶板、底板的压力分布对长宽比的变化较为敏感,上、下游侧斜腹板的压力分布受长宽比的影响较小。In order to improve the security of wind tunnel test data and understand the influence of end effect of section model on test results,In this paper,a combination of wind tunnel test and numerical simulation was used to produce multiple sets of section models with different length-width ratios for typical bridge sections to study the influence of length-width ratio of section models on the three component coefficients.The influence of the experimental errors of the three-component experiment on the aerostatic stability and buffeting response was analyzed by using the three component coefficients obtained from the model tests of different length-width ratios.In order to further expand the research scope of the length-width ratio of the model,the CFD method was used to reproduce the wind tunnel test,and the aerodynamic force and flow field analysis of multiple length-width ratio models were carried out under the premise of ensuring the accuracy of numerical simulation.The influence law of end effect of different length-width ratio models was systematically summarized.The results show that in order to guarantee the precision and stability of the force test results,it is recommended that the length-width ratio of the section model be greater than or equal to 3.For the section of streamline box girder,the demands can be relaxed appropriately,and the length-width ratio of section model should be≥2.When the length-width ratio is less than the suggested values,the obtained aerostatic stability results and buffeting response results are jeopardy.The smaller the length-width ratio,the greater the bias.The dimensionless length of the unilateral’affected zone’of the resistance coefficient of streamlined box girder is about 1,and the dimensionless length of the unilateral’affected zone’of the lift moment coefficient is about 0.6.The dimensionless length of the unilateral’affected zone’ of the lift coefficient is significantly larger than that of other aerodynamic coefficients.The pressure distribution of the top

关 键 词：桥梁工程 长宽比 风洞试验 节段模型 端部效应 三分力系数 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]