高鐵隧道間斷型緩沖結(jié)構(gòu)的氣動(dòng)效應(yīng)分析

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GAO Limin,YAN Yaguang,YANG Binbin,SHAO Jianheng,REN Yuan (School of Civil Engineering,Hebei University of Engineering,Handan O56OOO, China)
Abstract:Withtherapid developmentof high-speedrailway,the problem of aerodynamic effectcaused bytrain breaking into thetunelisbecoming moreandmoreserious,inordertoreducetheharmofmicro-pressurewaveattheexitofthetunnelin thespeedimprovementoftheexistingline,anewtunnelbuferstructure,intermittentbuferstructure,isproposed.Basedon thethree-dimensional,compressbleandunsteadyN-Sequations,theaerodynamicefectofthewholeprocessofhigh-speed trainenteringthetunnel wassimulatedbyusing slipgrid technologyandnumerical simulation,andthecharacteristicsof the initialcompresion wavewereanalyzed.Theresultsshowthatthe discontinuous buferstructurecanefectivelyreduce the maximum peak valueof theinitial compression wave pressure gradient andslowdown therising speedofthe pressre curve,but has no obvious efectonthemaximum pressure.When the numberof intermitent buffer structures is 3sections,the cros $\ulcorner$ (204 sectional area is ,the length of a single section is 11m ,and the discontinuity distance is 0.5m ,the reduction effect is the best,reaching 54.38% :
Keywords: high- speed rail tunnel; buffer structure; compression waves;; pressure gradient
0 引言
當(dāng)高鐵駛?cè)胨淼罆r(shí),由于隧道壁面和列車車身的限制,列車前方空氣不能及時(shí)排開[1],從而使一部分空氣沿著隧道壁面和列車壁面之間的路徑向后運(yùn)動(dòng),形成繞流“列車風(fēng)”,另一部分空氣在列車的推動(dòng)下,以壓縮波的形式向隧道出口處傳播[2],壓縮波傳至洞口處時(shí),一部分沿原路徑以微氣壓波的形式向隧道出口外傳播,伴隨強(qiáng)烈的爆炸聲,影響周圍環(huán)境和建筑物;另一部分轉(zhuǎn)化為膨脹波向隧道入口方向反射[3],不斷發(fā)生壓縮波、膨脹波的轉(zhuǎn)化疊加,使隧道內(nèi)氣動(dòng)效應(yīng)更加復(fù)雜。(剩余7179字)