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1、第32卷第9期動(dòng)力工程學(xué)報(bào)VoI.32No.92012年9月JournalofChineseSocietyofPowerEngineeringSep.2012文章編號(hào):1674—7607(2012)09—0666—06中圖分類號(hào):TK263.3文獻(xiàn)標(biāo)識(shí)碼:A學(xué)科分類號(hào):470.30汽輪機(jī)葉頂間隙內(nèi)非定常流動(dòng)的數(shù)值分析曹麗華,張冬雪,胡鵬飛,李勇(東北電力大學(xué)能源與動(dòng)力工程學(xué)院,吉林132012)摘要:為了分析葉頂間隙泄漏渦的影響范圍、運(yùn)行軌跡和強(qiáng)度的變化規(guī)律,以某汽輪機(jī)高壓級(jí)為研究對(duì)象,采用SS
2、Tk-w湍流模型,應(yīng)用PISO算法對(duì)葉項(xiàng)間隙內(nèi)的非定常流動(dòng)進(jìn)行了數(shù)值模擬.結(jié)果表明:葉頂間隙泄漏流是有規(guī)律的周期性的非定常流動(dòng),泄漏渦的影響范圍、運(yùn)行軌跡和強(qiáng)度隨時(shí)間和葉頂間隙的變化而變化;泄漏流對(duì)主流的影響呈現(xiàn)出從弱到強(qiáng)、再?gòu)膹?qiáng)到弱的周期性變化規(guī)律;葉頂間隙泄漏渦在?。?時(shí)刻的強(qiáng)度和影響范圍均達(dá)到最大,在T/2時(shí)刻,靜葉脫落渦和動(dòng)葉吸力面前部的泄漏渦混合形成新的渦系,而動(dòng)葉吸力面后部的泄漏渦卻與其邊界層的脫渦混合,離開吸力面.關(guān)鍵詞:汽輪機(jī);葉頂間隙;泄漏渦;非定常流動(dòng);數(shù)值模擬Numeric
3、alAnalysisonUnsteadyFlowinBladeTipClearanceofSteamTurbinesCAOLi—hua,ZHANGDong—xue,HUPeng—fei,LIYong(SchoolofEnergyandPowerEngineering,NortheastDianliUniversity,Jilin132012,China)Abstract:Takingthebladetipclearanceinhigh—pressurestageofsteamturbineasa
4、nobjectofstudy,nu—mericalsimulationwasperformedonunsteadyleakageflowintheclearanceusingk-wsstturbulencemodelandPISOalgorithm,SOastoanalyzetheincidence,trajectoryandintensityoftheleakagevortex.Resultsshowthatthetipleakageflowisofthecyclicandunsteadyty
5、pe;theincidence,trajectoryandintensityoftheleakagevortexvarywiththetimeandtipclearanceheight;theeffectoftipleakageflowonmainstreamexhibitsaregularvariation,fromweaktostrong,andthenfromstrongtoweak;thestrengthandinci—denceoftheleakagevortexreachtheirm
6、aximumsatT/4;andatT/2,thetail—edgesheddingvortexofsta-torblademixwiththeleakagevortexinthefrontofsuctionsurfaceofrotorblade,creatinganewvortexsystem,whiletheleakagevortexintherearofsuctionsurfaceofrotorblademixwiththeseparationvor—texatitsboundary,le
7、avingthesuctionsurfaceofrotorblade.Keywords:steamturbine;bladetipclearance;leakagevortex~unsteadyflow;numericalsimulation葉頂間隙泄漏損失是動(dòng)葉損失和汽輪機(jī)級(jí)內(nèi)損間隙汽流激振嚴(yán)重地威脅著汽輪機(jī)的安全運(yùn)行。].失的主要來源.在某些工況下,可以分別占到動(dòng)葉因此,葉頂間隙泄漏渦和間隙流動(dòng)問題的研究受到損失和級(jí)內(nèi)損失的45和3O[.另一方面,葉頂了國(guó)內(nèi)外學(xué)者的極大關(guān)注.收稿日期:201
8、2-03—07修訂日期:2012-04—05基金項(xiàng)目:吉林市科技發(fā)展計(jì)劃資助項(xiàng)目(201030003);東北電力大學(xué)博士基金資助項(xiàng)目(BSJXM一201203)作者簡(jiǎn)介:曹麗華(1973一),女,山東單縣人,副教授,工學(xué)博士。研究方向?yàn)椋浩啓C(jī)內(nèi)部流動(dòng)的數(shù)值分析與熱經(jīng)濟(jì)性診斷電話(Te1.):0432—64807479;E—mail:clh320@163.com.第9期曹麗華,等:汽輪機(jī)葉頂間隙內(nèi)非定常流動(dòng)的數(shù)值分析Gier等[5的研究表明,泄漏流所導(dǎo)致的損失表1葉片的幾何尺寸中,50以上是因與