尹庭赟,裴 吉,袁壽其,王文杰
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余熱排出泵葉輪流固耦合特性分析
尹庭赟,裴 吉※,袁壽其,王文杰
(江蘇大學(xué)國家水泵及系統(tǒng)工程技術(shù)研究中心,鎮(zhèn)江 212013)
余熱排出泵長期在高溫高壓環(huán)境下運行,其結(jié)構(gòu)的可靠性對整個機組的安全運行有著重要的影響。該文采用單向流固耦合方法研究了幾種常用材料及增加葉輪蓋板厚度對轉(zhuǎn)子結(jié)構(gòu)動力學(xué)特性的影響,同時對比了常溫和高溫下葉輪的振動特性。結(jié)果表明,余熱排出泵高溫運行時,葉輪的第1階固有頻率為394.17 Hz,較常溫下升高了2.28%,遠(yuǎn)高于葉輪葉片通過頻率。在各階模態(tài)振型下,1Cr13MoS葉輪固有頻率最大,ZG225-450葉輪固有頻率最小。設(shè)計工況和偏工況下葉輪的應(yīng)力及變形變化趨勢基本一致,葉輪的變形隨半徑的增加而不斷增大,最大變形量出現(xiàn)在后蓋板葉輪出口處。葉輪的應(yīng)力分布不均,最大應(yīng)力均出現(xiàn)在葉片尾緣與后蓋板接合處。沿著前蓋板和葉片接合線,應(yīng)力的峰值隨前蓋板厚度增加而減小。沿著后蓋板和葉片接合線,增加后蓋板厚度明顯減小了應(yīng)力峰值。高溫和常溫應(yīng)力變化趨勢基本一致,但是高溫下葉輪應(yīng)力明顯高于常溫。尤其在葉輪進(jìn)口處附近,高溫應(yīng)力相對于常溫應(yīng)力增加超過300%。該研究結(jié)果為下一步進(jìn)行更加復(fù)雜的動力學(xué)分析、疲勞分析以及結(jié)構(gòu)優(yōu)化提供參考。
泵;葉輪;動力學(xué);余熱排出泵;蓋板厚度
隨著中國對核電的高度重視,國內(nèi)高校和泵企業(yè)等正加緊研制開發(fā)核電用泵,實現(xiàn)核電用泵的國產(chǎn)化。在核電站內(nèi)的泵類設(shè)備中,余熱排出泵是重要的設(shè)備之一,可保護核電站的安全運行:當(dāng)反應(yīng)堆進(jìn)行正常停堆時,排出堆芯余熱和核主泵在一回路中產(chǎn)生的熱量;當(dāng)發(fā)生嚴(yán)重事故時,減小核電站受損程度[1-2]。由于余熱排出泵高溫高壓運行環(huán)境的特殊性,其結(jié)構(gòu)的可靠性對整個機組的安全運行有著重要的影響,因此,準(zhǔn)確地對余熱排出泵轉(zhuǎn)子部件進(jìn)行強度分析可為其結(jié)構(gòu)設(shè)計及壽命延長提供依據(jù)。
近年來,流固耦合有限元分析已成為分析流體機械可靠性的重要方法。國內(nèi)外不少學(xué)者嘗試采用流固耦合的方法對轉(zhuǎn)子系統(tǒng)進(jìn)行振動特性分析,取得了許多有價值的成果。劉厚林等[3]分別運用單、雙向流固耦合方法對導(dǎo)葉式離心泵葉輪進(jìn)行靜應(yīng)力強度分析,指出單向耦合即可滿足葉輪靜力學(xué)分析。Kan等[4]采用單向流固耦合計算得到了水輪機轉(zhuǎn)子在多工況下應(yīng)力和變形變化規(guī)律。牟介剛等[5]采用單向流固耦合方法,分析了懸臂式離心泵在不同懸臂比、不同工況下葉輪應(yīng)力和變形的變化規(guī)律,并對不同懸臂比離心泵的轉(zhuǎn)子動力學(xué)特性進(jìn)行研究。Schneider等[6]對多級離心泵進(jìn)行了單向流固耦合計算,分析了葉輪結(jié)構(gòu)設(shè)計參數(shù)和溫度對葉輪應(yīng)力和變形的影響。劉厚林等[7]對比分析了無預(yù)應(yīng)力下、流固耦合作用力和旋轉(zhuǎn)離心力作用下的余熱排出泵轉(zhuǎn)子的模態(tài)。劉建瑞等[8]考慮了水的附加質(zhì)量對余熱排出泵轉(zhuǎn)子振動性能的影響,對轉(zhuǎn)子進(jìn)行水中模態(tài)分析。Zhou等[9-10]采用雙向流固耦合計算方法,研究了考慮流固耦合作用的余熱排出泵在不同工況下內(nèi)部流場及轉(zhuǎn)子應(yīng)力和變形分布。考慮到余熱排出泵實際高溫高壓的運行環(huán)境,目前很少有學(xué)者考慮對葉輪蓋板進(jìn)行加厚處理。同時,材料屬性對轉(zhuǎn)子動力學(xué)特性的影響研究較少,尤其是對于有特殊用途的余熱排出泵而言,合理選擇葉輪材料至關(guān)重要。
因此,本文應(yīng)用單向流固耦合計算方法研究了余熱排出泵實際高溫運行環(huán)境下葉輪模態(tài)分布,詳細(xì)分析了葉輪幾種常用材料和不同蓋板厚度下葉輪變形量和應(yīng)力分布,以期為研究整個系統(tǒng)的動態(tài)特性提供參考。
1.1 基于模態(tài)分析的靜流體整體耦合法
對于具有個自由度的系統(tǒng),其結(jié)構(gòu)動力方程為
式中是系統(tǒng)的質(zhì)量矩陣;是系統(tǒng)的阻尼矩陣;是系統(tǒng)的剛度矩陣;是系統(tǒng)承受的載荷,Pa;是節(jié)點的加速度矢量,m/s2;是節(jié)點的速度矢量,m/s;是節(jié)點的位移矢量,m[11]。
在靜流體中,考慮到流固耦合作用對方程做了一些假設(shè):流體是可壓縮的,壓力波動將會引起密度變化;流體是非黏性的(即無黏性耗散)以及非旋轉(zhuǎn)的;流體沒有運動。因此,流體將被視為聲學(xué)流體,控制方程可用如下的聲波方程表示
(3)
式中是聲音在水中的傳播速度,m/s;是由聲波引起的流體壓力以及作用于流體的力,Pa;Δ是拉普拉斯算子;是流體體積模量;是時間,s;0是流體平均密度,kg/m3[11]。
在流固耦合交界面,用如下的方程描述了流體與結(jié)構(gòu)的相互作用
(5)
考慮到在交界面處壓力對結(jié)構(gòu)的影響,方程(1)改寫為
其中,= -表示等效耦合剛度[11]。
因此,可以耦合流體和結(jié)構(gòu)方程,基于單一求解器通過整體求解方法同時求解[11],方程表達(dá)如下
在對葉輪進(jìn)行模態(tài)分析時,自由振動方程系統(tǒng)視為非阻尼情況[11],方程(7)簡化如下
(8)
1.2 基于應(yīng)力和變形分析的動流體分區(qū)耦合法
在分區(qū)耦合法中,有2種耦合求解流體動力學(xué)和結(jié)構(gòu)響應(yīng)策略:單向耦合和雙向耦合[12]。雙向耦合方法主要是針對具有強物理耦合效應(yīng)的問題,即除了考慮流動對結(jié)構(gòu)的影響,結(jié)構(gòu)的變形或運動對流動的反作用也需要考慮[13]。在泵機械中,大多數(shù)情況下由于泵內(nèi)不穩(wěn)定流引起的葉輪的變形很小,而葉輪變形和振動對流場影響可以忽略不計[10,14]。因此,本文采用單向耦合方法,如圖1所示,在每一個時間步長流體載荷通過交界面單向傳遞到結(jié)構(gòu)。
2.1 計算模型
余熱排出泵過流部件包括后掠扭曲葉輪、徑向?qū)~和環(huán)形蝸殼3部分,其三維結(jié)構(gòu)如圖2所示。余熱排出泵的主要性能和幾何參數(shù)分別為設(shè)計流量d=910 m3/h,揚程d=77 m,轉(zhuǎn)速=1 490 r/min,比轉(zhuǎn)數(shù)s=104.5,葉輪進(jìn)口直徑j(luò)=270 mm,葉輪出口直徑2=511 mm,葉輪葉片數(shù)i=5,導(dǎo)葉進(jìn)口直徑3=515 mm,導(dǎo)葉出口直徑4=718 mm,導(dǎo)葉葉片數(shù)g=7,蝸殼基圓直徑5=840 mm。為探討增加蓋板厚度對轉(zhuǎn)子結(jié)構(gòu)動力學(xué)特性的影響,設(shè)計了4種不同的葉輪結(jié)構(gòu):1)原始蓋板;2)前蓋板厚度增加50%;3)后蓋板厚度增加50%;4)前后蓋板厚度均增加50%,詳細(xì)參數(shù)見表1。余熱排出泵長期在高溫高壓環(huán)境惡劣環(huán)境下運行,葉輪材料的選取至關(guān)重要。因此本文選取5種常用材料[15]如表2所示,分析了不同材料葉輪的動力學(xué)特性。
2.2 網(wǎng)格劃分
2.2.1 流體域網(wǎng)格
網(wǎng)格劃分是數(shù)值模擬中的重要步驟之一,網(wǎng)格的好壞直接影響數(shù)值模擬的準(zhǔn)確性。對余熱排出泵計算域采用ICEM軟件進(jìn)行結(jié)構(gòu)化網(wǎng)格劃分,對壁面進(jìn)行網(wǎng)格加密[16-17],如圖3所示。對數(shù)值模擬進(jìn)行網(wǎng)格無關(guān)性檢查,如圖4所示,確定余熱排出泵計算域的最終網(wǎng)格總數(shù)為5.20×106。
表1 葉輪結(jié)構(gòu)參數(shù)
表2 葉輪材料參數(shù)
2.2.2 結(jié)構(gòu)域網(wǎng)格
為研究濕模態(tài)下葉輪的動力學(xué)特性,將葉輪完全淹沒在1.12 m×0.36 m×1.12 m的水體中[18]。如圖5所示,運用ANSYS Workbench中自帶的網(wǎng)格劃分軟件,對葉輪及水體部分進(jìn)行網(wǎng)格劃分[19]。分別基于Method和Hex Dominant網(wǎng)格類型通過Sizing命令對葉輪和水體域進(jìn)行網(wǎng)格劃分。經(jīng)網(wǎng)格無關(guān)性檢查,確定最終網(wǎng)格節(jié)點總數(shù)為129 220,網(wǎng)格單元總數(shù)為49 556。
2.3 邊界條件
采用整體耦合法對葉輪進(jìn)行模態(tài)分析時,為了獲得更高的求解精度,用Fluid220和221高階單元作為水體域單元,默認(rèn)使用Solid186和187作為結(jié)構(gòu)域單元。由于水體域單元不支持完全積分法,所以本文對水體域積分控制使用縮減積分法,而對流固耦合面的固體域積分控制使用完全積分法。考慮到濕模態(tài)分析時,構(gòu)成結(jié)構(gòu)動力學(xué)有限元方程的質(zhì)量矩陣是非對稱的,因此在求解中需選用非對稱模態(tài)算法[20]。
假設(shè)流體在泵內(nèi)部是不可壓縮三維湍流流動,滿足連續(xù)方程和動量方程,采用SST湍流模型求解雷諾時均方程[21-24]。采用分區(qū)耦合法對葉輪進(jìn)行應(yīng)力和變形量分析時,先對流體域進(jìn)行了三維定常和非定常數(shù)值模擬:在定常計算過程中,邊界條件設(shè)置為總壓進(jìn)口和質(zhì)量流量出口,動靜域之間交界面采用Frozen rotor,計算域壁面采用無滑移網(wǎng)格函數(shù)[25-26],采用高階求解精度,收斂殘差RMS設(shè)置為10-5,計算迭代步數(shù)最大500;在非定常數(shù)值計算過程中,以定常計算結(jié)果作為初始值,邊界條件設(shè)置不變,而動靜域之間交界面改成Transient frozen rotor[27]。計算周期為6圈,葉輪旋轉(zhuǎn)1度為1個時間步長,即5.747 13×10-5s。以非定常計算最后一步的計算結(jié)果作為初值對葉輪進(jìn)行了6圈單向流固耦合計算:時間步長設(shè)置和非定常計算一致;流體場和固體場葉輪葉片、前后蓋板設(shè)置為流固耦合交界面(fluid-structure interface);有限元時間積分采用采用Hilber-Hughes- Taylor(HTT)離散方法,使用瑞利阻尼(Rayleigh damping)系數(shù)來定義結(jié)構(gòu)瞬態(tài)阻尼效應(yīng)[28]。如圖1所示,設(shè)置葉輪后蓋板的孔面為Fixed Support支撐面。本文分別模擬了設(shè)計工況下25 ℃常溫水以及180 ℃高溫水余熱排出泵內(nèi)部流動以對比實際運行環(huán)境下葉輪的動力學(xué)特性。
2.4 試驗驗證
為了驗證數(shù)值模擬的準(zhǔn)確性,對余熱排出泵按比例縮小30%的模型泵進(jìn)行了外特性試驗驗證。試驗在江蘇大學(xué)流體機械質(zhì)量技術(shù)檢驗中心的開式試驗臺上進(jìn)行,試驗現(xiàn)場如圖6所示。采用上海自儀九儀表有限公司生產(chǎn)的型號規(guī)格為LWGY-200A渦輪流量計進(jìn)行測量流量,量程為0~1.6 MPa,精確度為0.5級;采用上海威爾泰儀器儀表有限公司生產(chǎn)的WT200智能壓力變送器測量進(jìn)出口壓力,進(jìn)出口處壓力變送器的測量量程分別為?0.1~0.1 MPa和0~1.6 MPa,測量精度均為0.1級。如圖7所示,根據(jù)相似換算原理[29-30],得到了真實尺寸泵的試驗和數(shù)值模擬性能曲線。由圖7可知,試驗揚程和效率略高于計算值,預(yù)測揚程的最大偏差為6.78%,預(yù)測效率的最大偏差為9%。但是試驗結(jié)果趨勢一致,計算模型較準(zhǔn)確地預(yù)測了余熱排出泵的外特性,數(shù)值計算結(jié)果較為可信。
3.1 模態(tài)分析
為了了解葉輪模態(tài)振型情況,首先對原始蓋板的合金結(jié)構(gòu)鋼葉輪的計算結(jié)果提取分析。如圖8所示,葉輪第1、2階振型相似,都是在葉輪某2個對稱位置的變形量最大,即葉輪是擺動變形。第3、4階模態(tài)振型相似,都是葉輪沿著軸向的扭動變形。第5階和第6階模態(tài)振型相似,都是扭曲變形,可以看到2條明顯的節(jié)徑,且分布角度不同。第7、8、9、10階振型為葉輪前后蓋板沿著軸向的扭曲變形。通過對其他幾種形式的葉輪前10階模態(tài)振型分析發(fā)現(xiàn),葉輪振型基本相同,但是固有頻率有一定差別。
表3列出了不同材料、蓋板厚度和溫度下葉輪前10階固有頻率。由表3可知,改變?nèi)~輪蓋板厚度對前6階固有頻率的影響可以忽略。從第7階開始,葉輪后蓋板的厚度對固有頻率有很大影響,增加后蓋板厚度可以提高葉輪的固有頻率。5種材料的葉輪固有頻率變化規(guī)律趨于一致。在常溫各階模態(tài)振型下,1Cr13MoS(B_3)葉輪固有頻率最大,ZG225-450(B_2)葉輪固有頻率最小。以合金結(jié)構(gòu)鋼(B_0)原始蓋板葉輪為例,余熱排出泵在高溫運行時,葉輪的第1階固有頻率為394.17 Hz,較常溫下升高了2.28%,遠(yuǎn)高于高于葉輪葉片通過頻率,在安全運行范圍內(nèi)。
3.2 應(yīng)力和變形分析
如圖9、10所示分別為葉輪在3種工況下變形及應(yīng)力分布,其中對變形量和應(yīng)力進(jìn)行了無量綱處理[7],從圖中可以看出在設(shè)計工況和偏工況下葉輪的應(yīng)力及變形變化趨勢基本一致。葉輪的變形隨半徑的增大而不斷增大,最大總變形出現(xiàn)在后蓋板葉輪出口處。葉輪的應(yīng)力分布不均,最大應(yīng)力均出現(xiàn)在葉片尾緣與后蓋板接合處。
為了詳細(xì)分析葉輪關(guān)鍵部位的應(yīng)力變化,如圖11定義了前后蓋板和葉片接合處的4條路徑,這4條路徑在葉輪表面從進(jìn)口前緣延伸到出口尾緣。
圖12為不同工況下葉輪4條路徑應(yīng)力分布圖。從圖12中可以看出3種工況下4條路徑應(yīng)力變化趨勢基本一致:在前后蓋板與葉片壓力面接合處,路徑中間附近出現(xiàn)應(yīng)力峰值,在前緣附近可以明顯的看出大流量工況下應(yīng)力大,小流量工況下應(yīng)力小;在前后蓋板與葉片吸力面接合處,最大應(yīng)力均出現(xiàn)在尾緣處。其中,葉片吸力面與蓋板接合處的應(yīng)力峰值遠(yuǎn)高于與壓力面接合處的應(yīng)力峰值。
余熱排出泵的實際運行環(huán)境對葉輪材料的選擇提出了苛刻的要求,如圖13所示為設(shè)計工況下5種葉輪材料的4條路徑應(yīng)力分布圖。從圖13中可以看出5種材料的4條路徑應(yīng)力變化趨勢基本一致,但是在前緣附近合金結(jié)構(gòu)鋼(B_0)的應(yīng)力明顯高于其他4種材料。
如圖14所示為設(shè)計工況下4種葉輪蓋板厚度對應(yīng)的4條路徑應(yīng)力分布圖。從圖14b和14d中可以看出,沿著前蓋板和葉片接合線,應(yīng)力的峰值隨前蓋板厚度增加而減小。從圖14a和14c中可以看出,沿著后蓋板和葉片接合線,增加后蓋板厚度明顯減小了應(yīng)力峰值。
圖15所示對比分析了設(shè)計工況下原始模型葉輪在常溫和高溫下4條路徑應(yīng)力。由圖15可知,兩種溫度下四條路徑應(yīng)力變化趨勢基本一致,但是高溫下葉輪應(yīng)力明顯高于常溫。尤其在葉輪進(jìn)口處附近,高溫應(yīng)力相對于常溫應(yīng)力增加超過300%。在前蓋板和葉片壓力面接合處,常溫時應(yīng)力峰值在路徑中間附近,而高溫時峰值在尾緣。其余3種路徑峰值位置沒有改變。
本文應(yīng)用單向流固耦合計算方法分析了余熱排出泵實際高溫運行環(huán)境下葉輪動力學(xué)特性,并定量研究了葉輪不同結(jié)構(gòu)設(shè)計參數(shù)和不同材料下的變形量和應(yīng)力,結(jié)論如下:
1)余熱排出泵高溫運行時,葉輪的第1階固有頻率為394.17 Hz,較常溫下升高了2.28%,遠(yuǎn)高于葉輪葉片通過頻率。在各階模態(tài)振型下,1Cr13MoS的葉輪固有頻率最大,ZG225-450葉輪固有頻率最小。改變?nèi)~輪蓋板厚度對前6階固有頻率影響可以忽略。但是從第7階開始,增加后蓋板厚度可以提高葉輪的固有頻率。
2)設(shè)計工況和偏工況下葉輪的應(yīng)力及變形變化趨勢基本一致。葉輪的變形隨半徑的增大而不斷增大,最大總變形出現(xiàn)在后蓋板葉輪出口處。葉輪的應(yīng)力分布不均,最大應(yīng)力均出現(xiàn)在葉片與后蓋板接合的進(jìn)口處。其中,沿著前蓋板和葉片接合線,應(yīng)力的峰值隨前蓋板厚度增加而減小。沿著后蓋板和葉片接合線,增加后蓋板厚度明顯減小了應(yīng)力峰值。
3)高溫和常溫應(yīng)力變化趨勢基本一致,但是高溫下葉輪應(yīng)力明顯高于常溫。尤其在葉輪進(jìn)口處附近,高溫應(yīng)力相對于常溫應(yīng)力增加超過300%。在前蓋板和葉片壓力面接合處,常溫時應(yīng)力峰值在路徑中間附近,而高溫時峰值在尾緣。其余3種路徑峰值位置沒有改變。后文將在本文基礎(chǔ)上深入分析高溫高壓條件下泵的轉(zhuǎn)子動力學(xué)特性及葉輪使用壽命評估。
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Analysis of fluid-structure interaction characteristics for impeller of residual heat removal pump
Yin Tingyun, Pei Ji※, Yuan Shouqi, Wang Wenjie
(,,212013,)
In recent years, nuclear power has drawn increased attention because of its high efficiency and low pollution. Thus, a rising number of nuclear power stations are being constructed. The safety of nuclear station operations is mainly guaranteed by the residual heat removal system. Residual heat removal pumps (RHRP) are operated when the nuclear main pump stops working and the nuclear station needs to be maintained. The RHRP works in a complex environment, and its work status directly affects the performance of the entire plant. To ensure the reliability of the RHRP, the vibration characteristics of the rotor were analyzed using fluid-structure interaction theory. Stress and deformation analysis by partitioned solution for an impeller in a moving fluid was performed, and modal analysis of the impeller by monolithic solution was conducted in still fluid. For the partitioned method, there are two strategies for coupled solutions of dynamic fluid and structure interaction, one-way coupling and two-way coupling. Two-way coupling is typically used for large structural deformations. One-way coupling is suitable for the small structural deformation cases. In pump machinery, the impeller vibration caused by unsteady flow results in small deformations. Additionally, the feedback of the impeller motion onto the flow is small and therefore, can be neglected for most cases. Consequently, one-way coupling has been chosen, in which dynamic forces are transferred to the structure through the interface in a single direction at every time step. To understand the influence of the impeller shroud thickness on the resulting vibration characteristics, three impeller modifications were investigated and compared to the initial geometry under different flow rates. Moreover, five commonly used materials for an impeller were also evaluated. The three-dimensional turbulent flow was modeled utilizing a SST-turbulence model, and the numerical results were verified by the experimental data. The results showed that due to local structural differences between the pumps used in the numerical calculation model and the test measurement, as well as other effects, such as mesh quality, it was inevitable that there would be differences between the numerical calculation and the test measurements. However, the overall external characteristics of the numerical simulation were generally consistent with the performance of the test measurements, indicating that the flow-field calculation model can accurately predict its performance. By comparing with impellers adapted from four other materials and different shroud thicknesses, the vibration modes of the impellers were basically same for each order; however, the natural frequencies differed to some extent. The first order frequency of original impeller rotor was 394.17 Hz at hot condition and increased by 2.28% compared with cold condition, which was higher than blade passing frequency. Natural frequency of 1Cr13MoS was the highest among employed materials for each order mode, while ZG225-450 was the lowest. At design and off-design flow rates, the stress and displacement fields were similar. The displacement grew from the hub to the outer diameter, and each blade passage had a local maximum on the rear shroud. Moreover, the higher equivalent stress values can be observed in the junction between blade and shroud. Under three operating points, the peak values of stresses occurred in the middle of the junction between shroud and blade pressure side. Decreasing the head caused a significant reduction at the beginning of the blade passage. The stresses along defined paths were almost independent of the front shroud thickness, but peak values could be significantly reduced with a thicker rear shroud. The trendy of stress distribution between hot and cold condition was basically same. However, stress of hot condition was higher than cold one. Especially nearby the leading edge of the impeller, stress of hot condition increased more than 300%, compared to cold one. The results provide a theoretical basis for improving system performance and further study for more complicated dynamic analysis and fatigue analysis.
pumps; impellers; kinetics; residual heat removal pump; shroud thickness
10.11975/j.issn.1002-6819.2017.09.010
TH38
A
1002-6819(2017)-09-0076-08
2016-10-27
2017-04-05
國家科技支撐計劃項目(2014BAB08B01);國家自然科學(xué)基金青年基金(51409123);江蘇省自然科學(xué)基金青年基金(BK20140554);江蘇大學(xué)“青年骨干教師培養(yǎng)工程”
尹庭赟,男,博士生,主要從事水力機械空化空蝕機理研究。鎮(zhèn)江 江蘇大學(xué)國家水泵及系統(tǒng)工程技術(shù)研究中心,212013。 Email:tingyun_YIN@ujs.edu.cn
裴 吉,男,博士,副教授,主要從事離心泵非定常流動特性及流固耦合機理。鎮(zhèn)江 江蘇大學(xué)國家水泵及系統(tǒng)工程技術(shù)研究中心,212013。Email:jpei@ujs.edu.cn
尹庭赟,裴 吉,袁壽其,王文杰. 余熱排出泵葉輪流固耦合特性分析[J]. 農(nóng)業(yè)工程學(xué)報,2017,33(9):76-83. doi:10.11975/j.issn.1002-6819.2017.09.010 http://www.tcsae.org
Yin Tingyun, Pei Ji, Yuan Shouqi, Wang Wenjie. Analysis of fluid-structure interaction characteristics for impeller of residual heat removal pump[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2017, 33(9): 76-83. (in Chinese with English abstract) doi:10.11975/j.issn.1002-6819.2017.09.010 http://www.tcsae.org