郄志紅,郭麗云,吳鑫淼,冉彥立
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太極式魚道水力特性試驗(yàn)研究及數(shù)值模擬
郄志紅,郭麗云,吳鑫淼,冉彥立
(河北農(nóng)業(yè)大學(xué)城鄉(xiāng)建設(shè)學(xué)院,保定 071001)
針對(duì)傳統(tǒng)魚道一經(jīng)建成,其固體邊界條件已經(jīng)固定,池室內(nèi)水流流速分布變化不大而難以適應(yīng)多種魚類通過的缺點(diǎn),該文研究一種通過太極圓盤和八卦爻條消減水流能量,形成多態(tài)流速場以適應(yīng)多種魚類洄游的太極式新型魚道,并對(duì)其進(jìn)行了水力模型試驗(yàn)和數(shù)值分析。首先通過模型試驗(yàn)得到了魚道在不同工況下的流態(tài)和沿程水深變化,然后通過數(shù)值計(jì)算得到了與模型試驗(yàn)相近的結(jié)果,并進(jìn)一步分析了太極式魚道的表面流速、近底流速及關(guān)鍵橫斷面流速分布。結(jié)果表明:太極式新型魚道具有顯著的消能減速效果,最淺處水深達(dá)到無太極圓盤時(shí)相應(yīng)最淺水深的2倍左右,斷面平均最大流速為0.95 m/s,相對(duì)于無太極圓盤的情況降低50%左右,池室內(nèi)水流呈現(xiàn)多態(tài)化,另外隨太極圓盤方位不同流速場亦有明顯變化,該種魚道可為魚類提供更多適宜的洄游條件。
流速;模型;流體力學(xué);太極式;魚道;數(shù)學(xué)仿真模擬;流態(tài)
水利工程在興利除害的同時(shí)有時(shí)也帶來一定的負(fù)面影響,如攔河工程會(huì)在一定程度上破壞河流的連通性,阻斷魚類的洄游通道[1-5]。魚道是改善河流連通性、保護(hù)物種多樣性的有效措施之一[6-11]。魚道在國外已有數(shù)百年的研究歷史,而在國內(nèi),魚道的研究歷史只有50多年。文獻(xiàn)檢索表明,國內(nèi)外諸多學(xué)者通過對(duì)魚道進(jìn)行大量的室內(nèi)試驗(yàn)研究與數(shù)值模擬計(jì)算研究,優(yōu)化了魚道內(nèi)部的水流流態(tài)與結(jié)構(gòu)布置尺寸,規(guī)范了魚道設(shè)計(jì)方法,對(duì)于舊式魚道的改建與新型高效魚道的建設(shè)起到了關(guān)鍵的技術(shù)指導(dǎo)作用。Rajaratnam等[12-13]通過對(duì)豎縫式魚道池室流場的試驗(yàn)研究發(fā)現(xiàn),在池室的長寬比為/=10:8時(shí),池室的流態(tài)穩(wěn)定。Liu等[14-15]對(duì)豎縫式魚道進(jìn)行了模型試驗(yàn)研究,測(cè)量了池室內(nèi)流速分布與紊動(dòng)特性等水力指標(biāo)。董志勇等[16-17]對(duì)同側(cè)、異側(cè)豎縫式魚道進(jìn)行了水力特性試驗(yàn)和放魚試驗(yàn),發(fā)現(xiàn)同側(cè)豎縫式魚道適用于中等流量情形,異側(cè)豎縫式魚道主流流速的沿程變化可用1條二次曲線描述。隨著計(jì)算機(jī)模擬技術(shù)的發(fā)展,徐體兵等[18]通過數(shù)值模擬計(jì)算研究發(fā)現(xiàn)魚道水池長寬比在8:8~10.5:8的范圍內(nèi),可以獲得較好的流態(tài)。張國強(qiáng)等[19]研究了豎縫寬度對(duì)水池內(nèi)水流結(jié)構(gòu)的影響,并給出豎縫寬度的合理取值范圍為/=0.15~0.20(、分別為豎縫寬度和池室寬度)。邊永歡等[20]的研究結(jié)果表明,豎縫斷面平均流速值在0.8~2.0 m/s范圍內(nèi)時(shí)對(duì)于各級(jí)水池內(nèi)主流區(qū)分布、主流流速的沿程衰減規(guī)律以及豎縫斷面流速分布并無顯著影響,并進(jìn)一步研究了豎縫斷面流速分布與各級(jí)水池內(nèi)主流流速分布的變化規(guī)律。除關(guān)于豎縫式魚道研究外,Yagci[21]和Ead等[22]分別對(duì)池堰式魚道的水力特性進(jìn)行了試驗(yàn)及理論研究;孫雙科等[23]對(duì)近自然魚道的設(shè)計(jì)方法和設(shè)計(jì)理念等進(jìn)行了分析闡述。
目前國內(nèi)仍有不少魚道運(yùn)行效果不理想,有的魚道甚至建成即遭廢棄,如七里壟電站的魚道自建成后就從未有魚、蝦、蟹通過,湖南洋塘魚道1980年建成,自1984年就處于廢棄狀態(tài)[24-27]。傳統(tǒng)魚道的設(shè)計(jì)大多針對(duì)河流中數(shù)量較多的某類魚群,但天然河流存在著不同的洄游時(shí)期,并且在每個(gè)洄游時(shí)期里相應(yīng)洄游魚類所適應(yīng)的流速不同,由于傳統(tǒng)魚道一經(jīng)建成,固體結(jié)構(gòu)形狀也就相對(duì)固定,盡管水流會(huì)因流量大小等因素有一定變化,但其流速分布等變化不大,因而難以適應(yīng)多種魚類通過,這便使得傳統(tǒng)魚道具有一定的局限性,可能導(dǎo)致過魚種類單一。因此本文將水力學(xué)與中國古代哲學(xué)思想相結(jié)合,提出一種通過太極圓盤和八卦爻條消減水流能量,且可形成多態(tài)流速場以適應(yīng)多種魚類洄游的太極式新型魚道,并采用室內(nèi)模型試驗(yàn)與數(shù)值模擬相結(jié)合的方法對(duì)該新型魚道的水力特性進(jìn)行初步分析。
太極式新型魚道是一種基于古代道家哲學(xué),以“太極八卦”變化的思想為基礎(chǔ),通過陰陽八卦運(yùn)動(dòng)營造多變水流環(huán)境,改善傳統(tǒng)魚道過魚種類單一的缺點(diǎn),形成多態(tài)流速場以適應(yīng)不同魚類及其他水生生物的生活習(xí)性。
池室是魚道的基本結(jié)構(gòu)單元。目前研究較多的豎縫式魚道,有同側(cè)豎縫和異側(cè)豎縫,通過池室的束窄和變寬改變水流的流態(tài),消減能量。而太極式魚道也是通過池室的收縮和擴(kuò)大,不同的是,太極式魚道池室邊壁采用圓弧曲線,池室之間相連的收縮區(qū)由反向圓弧平順銜接,通過水流的擴(kuò)散、匯聚消能。池室邊壁設(shè)置丁壩式隔板,相當(dāng)于外八卦爻條,上游來流經(jīng)過外八卦爻條時(shí)會(huì)受到阻力,消減能量,外八卦爻條亦可為洄游魚類提供休憩場所。池室中設(shè)置太極圓盤,圓盤上陰陽魚間的過流通道具有分散水流、減弱水流能量的作用,陰陽魚周圍設(shè)置與其一起固定在圓盤上的內(nèi)八卦爻條,本文為簡化起見,內(nèi)外八卦均僅采用單個(gè)陽爻。轉(zhuǎn)動(dòng)起來的太極圓盤與邊壁上的丁壩式隔板在不同的時(shí)刻組合成不同的運(yùn)行工況,為水流的多態(tài)性創(chuàng)造條件。圖1為太極式魚道設(shè)計(jì)概念和池室細(xì)部結(jié)構(gòu)圖。
圖1 太極式魚道設(shè)計(jì)概念和細(xì)部結(jié)構(gòu)
本文采用物理模型試驗(yàn)和數(shù)學(xué)仿真模擬相結(jié)合的方法研究太極式新型魚道在不同工況下的水流特性,用物理模型試驗(yàn)研究沿程水位變化和水流基本流態(tài),而對(duì)于物理模型難以測(cè)量的表面及內(nèi)部流速場分布情況則采用CFD數(shù)值模擬的方法。比較用這2種方法得到的沿程水位變化及水流基本流態(tài),用物理試驗(yàn)結(jié)果驗(yàn)證數(shù)值模擬的準(zhǔn)確性。
2.1.1 室內(nèi)試驗(yàn)設(shè)計(jì)
按照魚道設(shè)計(jì)相關(guān)規(guī)范[28],制作物理模型。模型尺寸依據(jù)重力相似準(zhǔn)則確定,具體尺寸如下:魚道寬度20 cm,魚道池室長度(即相鄰埡口間距)40 cm,魚道池室深度15 cm,豎縫寬度4 cm,坡度1:10,物理模型弧形邊壁的壁厚為1 cm,見圖2a。試驗(yàn)?zāi)P妥鴺?biāo)原點(diǎn)為休息室和池室1之間的進(jìn)水口斷面位置,測(cè)點(diǎn)選在魚道中心線與典型斷面的交點(diǎn)上,即=0.11 m與各個(gè)典型斷面的交點(diǎn),見圖2b。試驗(yàn)采用潛水泵循環(huán)供水系統(tǒng)供水,上游設(shè)置泄水孔用以調(diào)節(jié)上游水位。整體模型制作完成后,首先進(jìn)行“無太極圓盤和八卦爻條”(以下簡稱工況0)的過水試驗(yàn),并用測(cè)針測(cè)量選點(diǎn)的水深;安裝太極圓盤和八卦條后,再分2種工況測(cè)量魚道中心線上沿程水深,即S形通道近似正交或平行于魚道中心線2種情況,分別簡稱“工況1”和“工況2”,整體裝置、測(cè)點(diǎn)位置及3種工況示意圖見圖2。需要說明的是,為節(jié)省篇幅圖2c中分別以3個(gè)不同池室示出了3種工況,但試驗(yàn)當(dāng)中3個(gè)池室都對(duì)應(yīng)同一工況。
圖2 試驗(yàn)裝置、測(cè)量斷面及工況示意圖
2.1.2 過水試驗(yàn)
過水試驗(yàn)主要觀察水流流態(tài)和水深變化,采用水位測(cè)針測(cè)量中心線上典型測(cè)點(diǎn)(圖2b)處的水位,進(jìn)而計(jì)算水深。3種工況下的過水試驗(yàn)照片與水深測(cè)量結(jié)果如圖 3所示。在工況0條件下,由于魚道從埡口到池室過流斷面經(jīng)歷了較大由窄到寬的變化,水流從急流過渡到緩流,發(fā)生了水躍現(xiàn)象,水深由淺變深,水面起伏較大,見圖 3a。安裝太極圓盤之后,工況1和工況2條件下,仍然發(fā)生水躍現(xiàn)象,但相比于工況0水流狀況得到明顯改善,水面起伏平緩,見圖3b,其中最淺處水深由無太極圓盤時(shí)的5 mm增加至10~12 mm,最淺處水深的增加2倍左右,相應(yīng)地,斷面平均最大流速減小50%左右,說明加入太極裝置后的魚道消能減速效果明顯。
圖3 過水試驗(yàn)及測(cè)量水深
2.1.3 過魚試驗(yàn)
在過水試驗(yàn)的同時(shí)也進(jìn)行了過魚試驗(yàn)。
在工況0時(shí),將試驗(yàn)魚放在池室3中,試驗(yàn)魚在經(jīng)過奮力游泳之后勉強(qiáng)游過了2個(gè)池室到達(dá)池室1,隨后又被水流沖回池室2,說明魚道中流速過大,還應(yīng)采取進(jìn)一步的消能措施。
在工況1和工況2時(shí),試驗(yàn)魚輕松游過3個(gè)池室到達(dá)上游的水箱。試驗(yàn)說明,安裝太極圓盤和八卦爻條的消能和改變流態(tài)的效果明顯,增加了魚類洄游的舒適性。
2.2.1 數(shù)學(xué)模型
為進(jìn)一步分析水流特性,以物理試驗(yàn)?zāi)P蜑榛A(chǔ),對(duì)該太極式新型魚道建立數(shù)學(xué)模型,并進(jìn)行數(shù)學(xué)仿真模擬計(jì)算。數(shù)學(xué)計(jì)算模型按照物理試驗(yàn)?zāi)P统叽缭O(shè)計(jì),即魚道寬度0.20 m,魚道池室長度(即相鄰埡口間距)0.40 m,魚道池室深度0.15 m,豎縫寬度0.04 m,坡度1:10。
2.2.2 控制方程
對(duì)于復(fù)雜的流場研究,在一定程度上依賴于準(zhǔn)確的數(shù)值模擬結(jié)果。本次試驗(yàn)流體是水,根據(jù)流體力學(xué)理論,滿足連續(xù)介質(zhì)假設(shè)的流體運(yùn)動(dòng)可以用Navier-Stokes方程準(zhǔn)確計(jì)算。采用Navier-Stokes方程,建立太極式新型魚道三維水流RNG-紊流數(shù)學(xué)模型,控制方程包括連續(xù)性方程、動(dòng)量方程、紊動(dòng)能方程和紊動(dòng)能耗散率方程[29-31]:
連續(xù)性方程
動(dòng)量方程(N-S方程)
紊動(dòng)能方程
紊動(dòng)能耗散率方程
2.2.3 計(jì)算區(qū)域及邊界條件
取順?biāo)鞣较驗(yàn)檩S,寬度方向?yàn)檩S,高度方向?yàn)檩S,坐標(biāo)原點(diǎn)與圖2b相同,即取在魚道進(jìn)口斷面(=0)處。為使來流平穩(wěn),在=0~0.10 m是平底坡=0,坡面以下為實(shí)體。邊界條件:進(jìn)口斷面有一定高度的初始水位,設(shè)置為壓力進(jìn)口邊界;出口設(shè)為自由出流邊界;底部及兩側(cè)邊墻為固壁邊界,無滑移邊界條件;計(jì)算區(qū)域上方空氣入口設(shè)定為對(duì)稱邊界條件,即默認(rèn)無流體穿過該邊界。
2.2.4 網(wǎng)格劃分
模型整體用0.5 cm×0.5 cm×0.5 cm大小的網(wǎng)格劃分,由于池室結(jié)構(gòu)復(fù)雜,為提高模擬計(jì)算精度,網(wǎng)格劃分時(shí)對(duì)太極式魚道池室結(jié)構(gòu)用0.2 cm×0.2 cm×0.2 cm大小的網(wǎng)格進(jìn)行局部網(wǎng)格加密處理。
以數(shù)學(xué)計(jì)算模型計(jì)算得出的魚道中心線上沿程水深與物理模型試驗(yàn)結(jié)果的對(duì)比驗(yàn)證數(shù)學(xué)模型的準(zhǔn)確性。圖4為3種工況(工況0,1,2)下魚道中心線上實(shí)測(cè)與模擬水深的對(duì)比情況。結(jié)果表明,最大相對(duì)誤差在13.6%,小于15%的允許值[32],實(shí)測(cè)斷面水深與數(shù)值模擬計(jì)算斷面水深變化趨勢(shì)基本一致。
圖4 3種工況下模擬水深和測(cè)量水深
3.2.1 自由表面的流速場分析
模擬計(jì)算的工況1和工況2的表面的流速場見圖 5a、5b。工況1與工況2的主流部分表面流速分布有所不同,但總體情況相似,池室中水流均出現(xiàn)明顯分區(qū)現(xiàn)象,水流多態(tài)。池室中央?yún)^(qū)域受主流的影響,從埡口到池室中心,流速范圍為0.27~1.0 m/s,最大速度1.0 m/s,出現(xiàn)在太極圓盤的前端,結(jié)合斷面尺寸推算出斷面平均最大流速為0.95m/s。池室兩側(cè)的非主流區(qū)的流速整體低于0.13 m/s,流向偏向魚道中心線,特別是埡口附近近壁水流流向與主流流向近乎相反,形成兩側(cè)的回流區(qū),低流速和回流區(qū)可以為洄游魚提供較大區(qū)域的休憩場所,為沖擊埡口處的較大流速區(qū)積攢體力。魚沿池室邊壁洄游可有效避開最大流速區(qū),節(jié)省體力。
圖5a、5b還顯示順?biāo)飨蛳录?jí)池室的水流更加分散,主流區(qū)范圍擴(kuò)大,最大流速由1.0 m/s減小到0.9 m/s,流速減少0.1 m/s,水流自上而下逐級(jí)改善趨勢(shì)明顯。
3.2.2 臨底流速場分析
在數(shù)值模擬計(jì)算模型中,緊貼太極圓盤上表面做平行于底坡的剖面,該剖面與池室中心太極圓盤相交,觀察順?biāo)鞣较蛏吓R近底坡的流速場(圖5c、5d)。由于內(nèi)八卦爻條均采用單個(gè)陽爻,故工況1和工況2的主要區(qū)別是S型通道內(nèi)的水流流速,工況2中有水流通過,且流道前部流速較大。流速場的整體分布規(guī)律和趨勢(shì)與自由表面流速場大致相同,但與圖5a、5b相比,在太極圓盤后部的臨底流速小于0.25m/s,明顯小于表面流速,且在平面上分布較為均勻,這有賴于池室內(nèi)形成的水躍及太極裝置產(chǎn)生的底流消能作用。
圖5 工況1、2的表面流速場和臨底流速場
3.2.3 橫斷面的流速場分析
在池室1、池室2中圓盤上各選取一個(gè)橫斷面,其橫坐標(biāo)分別為=0.52 m、=0.80 m。斷面位置見圖6a,不同工況下橫斷面流速場分布見圖6b至圖6e。
在橫斷面=0.52 m處,工況1的斷面流速范圍0~0.40 m/s,最大流速0.40 m/s在斷面中心;工況2時(shí)的斷面流速范圍0~0.50 m/s,最大流速0.50 m/s在斷面中心,2種工況下,該橫斷面兩側(cè)的八卦爻條內(nèi)側(cè)流速均可達(dá)到0.30 m/s。在橫斷面=0.80 m處,工況1的斷面流速范圍0~0.33 m/s,最大流速0.33 m/s在兩側(cè)的八卦爻條內(nèi)側(cè),斷面中心流速較低;工況2的斷面流速范圍0~0.40 m/s,最大流速0.40 m/s在斷面中心及八卦爻條邊緣。各斷面流速場均呈現(xiàn)較強(qiáng)的多態(tài)性,且不同工況的橫斷面最大流速及流速分布均有明顯差異。另外,比較圖6b和圖6d(或者圖6c和圖6e),表明在同一種工況下,下級(jí)池室斷面最大流速小于上游斷面最大流速,說明水流得到了進(jìn)一步調(diào)整,使過魚阻力減小。
圖6 橫斷面位置及流速分布
太極式魚道的池室弧形邊壁和池室的設(shè)計(jì)與傳統(tǒng)魚道的相似之處在于通過過流通道的寬窄變化雍高埡口上游水位,在下游形成水躍,消減水流動(dòng)能,降低流速,以利過魚。不同的是融入了中國古代哲學(xué)思想,通過池室中的太極圓盤(含內(nèi)八卦爻條)轉(zhuǎn)動(dòng)及與池壁上的外八卦爻條(丁壩式隔板)的組合,營造空間上“多態(tài)”和“應(yīng)時(shí)而變”的水流,從而提高魚道的適用性。文章通過對(duì)無圓盤的魚道、太極圓盤的S形通道與水流近似正交與平行3種工況進(jìn)行過水試驗(yàn)、過魚試驗(yàn)及數(shù)學(xué)仿真模擬,得出以下主要結(jié)論:
1)與無太極裝置的情況相比,太極圓盤和內(nèi)外八卦條的組合顯著增強(qiáng)了魚道消能減速效果,最淺處水深達(dá)到無太極裝置時(shí)相應(yīng)最淺水深的2倍左右,斷面最大平均流速減小50%左右。
2)太極式魚道池室中的表面水流有明顯分區(qū)現(xiàn)象,水流多態(tài)。池室自中間向兩側(cè)依次形成主流區(qū)(流速變化范圍為0.27~1.0 m/s,最大流速出現(xiàn)在太極圓盤的前端)、低速區(qū)(流速低于0.13 m/s)和回流區(qū)。低速區(qū)和回流區(qū)可以為洄游魚提供休憩場所,魚沿池室邊壁洄游可有效避開最大流速區(qū),節(jié)省體力。
3)沿水流方向下級(jí)池室的水面最大流速低于上一級(jí)池室,流速減小0.1 m/s,水流自上而下主流區(qū)范圍擴(kuò)大、流態(tài)改善。
4)池室內(nèi)太極圓盤下游水流臨底流速分布均勻,小于0.25 m/s,且低于表面主流流速,水躍消能及太極裝置的輔助消能效果明顯。
5)池室內(nèi)典型橫斷面流速場呈現(xiàn)較強(qiáng)的多態(tài)性。不同工況下,=0.52 m斷面的流速最大變動(dòng)范圍為0~0.50 m/s,=0.80 m斷面的流速最大變動(dòng)范圍為0~0.40 m/s,橫斷面最大流速及流速分布均有明顯差異,說明池室中太極圓盤的S形通道處于不同方位可以使流速場分布相應(yīng)發(fā)生變化,即通過太極圓盤的轉(zhuǎn)動(dòng)可以使魚道的流速場隨時(shí)間而變化。
太極式新型魚道是一種新型魚道,目前尚處于研究和探索階段。由于影響流態(tài)的因素眾多,比如八卦爻條、S形通道、陰陽魚、丁壩式隔板的尺寸等,本文進(jìn)行的試驗(yàn)將八卦簡化為一圈隔墻,即只有一個(gè)陽爻,未形成真正的八卦,今后將進(jìn)一步研究這種新型魚道的結(jié)構(gòu)、尺寸、轉(zhuǎn)動(dòng)機(jī)構(gòu)等問題。
[1] Kim J H, Yoon J D, Baek S H, et al. An efficiency analysis of a nature-like fishway for freshwater fish ascending a large Korean River[J]. Water, 2016, 8(1): 1-18.
[2] 汪紅波,王從鋒,劉德富,等. 橫隔板式魚道水力特性數(shù)值模擬研究[J]. 水電能源科學(xué),2012,30(5):65-68,141.
Wang Hongbo, Wang Congfeng, Liu Defu, et al. Study on numerical simulation of hydraulic characteristics of transverse diaphragm plate fishway[J]. Water Resources And Power, 2012, 30(5): 65-68,141. (in Chinese with English abstract)
[3] 劉志雄,周赤,黃明海. 魚道應(yīng)用現(xiàn)狀和研究進(jìn)展[J]. 長江科學(xué)院院報(bào),2010,27(4):28-31,35.
Liu Zhixiong, Zhou Chi, Huang Minghai. Situation and development of fishway research and application[J]. Journal of Yangtze River Scientific Research Institute, 2010, 27(4): 28-31,35. (in Chinese with English abstract)
[4] 陳凱麒,常仲農(nóng),曹曉紅,等. 我國魚道的建設(shè)現(xiàn)狀與展望[J]. 水利學(xué)報(bào),2012,43(2):182-188.
Chen Kaiqi, Chang Zhongnong, Cao Xiaohong, et al. Status and prospection of fish pass construction in China[J]. Journal of Hydroecology, 2012, 43(2): 182-188. (in Chinese with English abstract)
[5] 陳凱麒,葛懷鳳,郭軍,等. 我國過魚設(shè)施現(xiàn)狀分析及魚道適宜性管理的關(guān)鍵問題[J]. 水生態(tài)學(xué)雜志,2013,34(4):1-6.
Chen Kaiqi, Ge Huaifeng, Guo Jun, et al. Study on the situation analysis of fish passages and the key issues of adaptive management in China[J]. Journal of Hydroecology, 2013, 34(4): 1-6. (in Chinese with English abstract)
[6] 鄭鐵剛,孫雙科,柳海濤,等. 基于魚類行為學(xué)與水力學(xué)的水電站魚道進(jìn)口位置選擇[J]. 農(nóng)業(yè)工程學(xué)報(bào),2016,32(24):164-170.
Zheng Tiegang, Sun Shuangke, Liu Haitao, et al. Location choice of fishway entrance in hydropower project based on fish behavioristics and hydraulics[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2016, 32(24): 164-170. (in Chinese with English abstract)
[7] 李捷,李新輝,潘峰,等. 連江西牛魚道運(yùn)行效果的初步研究[J]. 水生態(tài)學(xué)雜志,2013,34(4):53-57.
Li Jie, Li Xinhui, Pan Feng, et al. Preliminary study on the operating effect of Xiniu fishway in Lianjiang River[J]. Journal of Hydroecology, 2013, 34(4): 53-57. (in Chinese with English abstract)
[8] 南京水利科學(xué)研究所. 魚道[M]. 北京:電力工業(yè)出版社,1982.
[9] 王珂,劉紹平,段辛斌,等. 崔家營航電樞紐工程魚道過魚效果[J]. 農(nóng)業(yè)工程學(xué)報(bào),2013,29(3):184-189.
Wang Ke, Liu Shaoping, Duan Xinbin, et al. Fishway effect of Cuijiaying navigation-power junction project[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2013, 29(3): 184-189. (in Chinese with English abstract)
[10] Dvwk F. Fish passes: Design, dimensions and monitoring[J]. Fish Passes Design Dimensions & Monitoring, 2002.
[11] 曹慶磊,楊文俊,周良景. 國內(nèi)外過魚設(shè)施研究綜述[J].長江科學(xué)院院報(bào),2010,27(5):39-43.
Cao Qinglei, Yang Wenjun, Zhou Liangjing. Review on study of fishery facilities at home and abroad[J]. Journal of Yangtze River Scientific Research Institute, 2010, 27(5): 39-43. (in Chinese with English abstract)
[12] Rajaratnam N, Vinne G V, Katopodis C. Hydraulics of vertical slot fishways[J]. Journal of Hydraulic Engineering, 1986, 112(10): 909-927.
[13] Rajaratnam N, Katopadis C, Paccagnan R. Field studies of fishways in Albeta[J]. Canadian Journal of Civil Engineering, 1992, 19(4): 627-638.
[14] Liu M, Rajaratnam N, Zhu D Z. Mean flow and turbulence structure in vertical slot fishway[J]. Journal of Hydraulics Engineering, 2006, 132(8): 765-777.
[15] Wu S, Rajaratnam N, Katopodis C. Structure of flow in vertical slot fishway[J]. Journal of Hydraulics Engineering, 1999, 125(4): 351-360.
[16] 董志勇,馮玉平,Ervine A. 同側(cè)豎縫式魚道水力特性及放魚試驗(yàn)研究[J]. 水力發(fā)電學(xué)報(bào),2008,27(6):121-125.
Dong Zhiyong, Feng Yuping, Ervine A. An experimental study of hydraulic characteristic and fish test in vertical slot fishway to one side[J]. Journal of Hydroelectric Engineering, 2008, 27(6): 121-125. (in Chinese with English abstract)
[17] 董志勇,馮玉平,Ervine A. 異側(cè)豎縫式魚道水力特性及放魚試驗(yàn)研究[J]. 水力發(fā)電學(xué)報(bào),2008,27(6):126-130.
Dong Zhiyong, Feng Yuping, Ervine A. An experimental study of hydraulic characteristic and fish test in vertical slot fishway from side to side[J]. Journal of Hydroelectric Engineering, 2008, 27(6): 126-130. (in Chinese with English abstract)
[18] 徐體兵,孫雙科. 豎縫式魚道水流結(jié)構(gòu)的數(shù)值模擬[J]. 水利學(xué)報(bào),2009,40(11):1386-1391.
Xu Tibing, Sun Shuangke. Numerical simulation of the flow structure in the vertical slot fishway[J]. Journal of Hydraulic Engineering, 2009, 40(11): 1386-1391. (in Chinese with English abstract)
[19] 張國強(qiáng),孫雙科. 豎縫寬度對(duì)豎縫式魚道水流結(jié)構(gòu)的影響[J]. 水力發(fā)電學(xué)報(bào),2012,31(1):151-156.
Zhang Guoqiang, Sun Shuangke. Effect of slot width on the flow structure of vertical slot fishway[J]. Journal of Hydroelectric Engineering, 2012, 31(1): 151-156. (in Chinese with English abstract)
[20] 邊永歡,孫雙科. 豎縫式魚道的水力特性研究[J]. 水利學(xué)報(bào),2013,44(12):1462-1467.
Bian Yonghuan, Sun Shuangke. Study on hydraulic characteristic of flow in the vertical slot fishway[J]. Journal of Hydraulic Engineering, 2013, 44(12): 1462-1467. (in Chinese with English abstract)
[21] Yagci O. Hydraulic aspects of pool-weir fishways as ecologically friendly water structure[J]. Ecological Engineering, 2009, 36(1): 36-46.
[22] Ead S A, Katopodis C, Sikora G J, et al. Flow regimes and structure in pool and weir fishways[J]. Journal of Environmental Engineering and Science, 2004, 3(5): 379-390.
[23] 孫雙科,張國強(qiáng). 環(huán)境友好的近自然型魚道[J]. 中國水利水電科學(xué)研究院學(xué)報(bào),2012,10(1):41-47.
Sun Shuangke, Zhang Guoqiang. Environment-friendly fishway in close-to-nature types[J]. Journal of China Institute of Water Resources and Hydropower Research, 2012, 10(1): 41-47. (in Chinese with English abstract)
[24] 劉洪波. 魚道建設(shè)現(xiàn)狀、問題與前景[J]. 水利科技與經(jīng)濟(jì),2009,15(6):477-479.
Liu Hongbo. Current situation and questions and prospect of fishways construction[J]. Water Conservancy Science and Technology and Economy, 2009, 15(6): 477-479. (in Chinese with English abstract)
[25] 祁昌軍,曹曉紅,溫靜雅,等. 我國魚道建設(shè)的實(shí)踐與問題研究[J]. 環(huán)境保護(hù),2017,45(6):47-51.
Qi Changjun, Cao Xiaohong, Wen Jingya,et al. The practice and problems of the fishway construction in China[J]. Environmental Protection, 2017, 45(6): 47-51. (in Chinese with English abstract)
[26] 呂巍,王曉剛. 淺議我國魚道運(yùn)行管理存在的問題及對(duì)策:以洣水洋塘魚道為例[J]. 水生態(tài)學(xué)雜志,2013,34(4):7-9.
Lü Wei, Wang Xiaogang. Problems and countermeasures in operation management of fishways in China-taking Yangtze fishway as an example[J]. Journal of Hydroecology, 2013, 34(4): 7-9. (in Chinese with English abstract)
[27] 郭堅(jiān),芮建良. 以洋塘水閘魚道為例淺議我國魚道的有關(guān)問題[J]. 水力發(fā)電,2010,36(4):8-10.
Guo Jian, Rui Jianliang. Question and suggestion on fishway construction in China: Lesson learned from the operation of Yangtang lock fishway[J]. Water Power, 2010, 36(4): 8-10. (in Chinese with English abstract)
[28] 水利水電工程魚道設(shè)計(jì)導(dǎo)則:SL609-2013 [S]. 北京:中國水利水電出版社,2013.
[29] 肖苡辀,王文娥,胡笑濤. 基于FLOW-3D的田間便攜式短喉槽水力性能數(shù)值模擬[J]. 農(nóng)業(yè)工程學(xué)報(bào),2016,32(3):55-61.
Xiao Yizhou, Wang Wen’e, Hu Xiaotao. Numerical simulation of hydraulic performance for portable short-throat flume in field based on FLOW-3D[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2016, 32(3): 164-170. (in Chinese with English abstract)
[30] 呂宏興,裴國霞,楊玲霞. 水力學(xué)[M]. 北京:中國農(nóng)業(yè)出版社,2002.
[31] 王福軍. 計(jì)算流體動(dòng)力學(xué)分析:CFD軟件原理與應(yīng)用[M]. 北京:清華大學(xué)出版社,2004.
[32] Moriasi D N, Arnold J G, Liew M W V, et al. Model evaluation guidelines for systematic quantification of accuracy in watershed simulations[J]. Transactions of the American Society of Agricultural and Biological Engineers (Transactions of the ASABE), 2007, 50(3): 885-900.
Experimental study and numerical simulation of hydraulic characteristics of Tai Chi fishway
Qie Zhihong, Guo Liyun, Wu Xinmiao, Ran Yanli
(071001,)
Once the fishway is completed in the traditional style and the flow condition is basically fixed. It will be hard for a variety of fish to go through it at the same time. To solve the problem, in this paper, we developed a Tai Chi fish-way, which can form a rich flow regime and adapt to the migration of many fishes. Based on the ancient Taoist philosophy of “Tai Chi Eight Diagrams”, Tai Chi fishway created a flow changing environment when the eight diagrams rolled, which can offset the general fishway’s shortcoming, “once built, water conditions were basically fixed”. The pool room of the Tai Chi fishway was arc-shaped, which was connected by a reverse arc smoothly. Through the diffusion and aggregation of water, it can help the water flow more smoothly, and reduce the adverse effects of turbulence, vortex and so on. The wall of the pool room was provided with external eight diagrams (groyne type clapboards), which offered resistance to the water flow and helped change its direction when flowing through. The migratory fishes may rest below the external eight diagrams. Tai Chi disk was also set in the pool room and the S shaped channel on the disk had the function of dispersing water flow and dissipating energy. The Tai Chi disk and internal eight diagrams partition can rotate in certain cycles which were combined into different operating conditions at different times to create conditions for the polymorphism of the stream. For Tai Chi fishway had its unique pool room structure, the physical model test alone was difficult to capture the flow structure in detail, and it was time-consuming, too. We used a method combined with the physical model test and numerical simulation to study the flow characteristics of Tai Chi fishway in different conditions. Physical model test was used to study the variation of water level along the course and the basic flow pattern of water flow, and the CFD numerical simulation method was applied to determine the distribution of the surface and internal flow fields which were difficult to be measured by the physical model. Then the water level and flow pattern were compared and verified with each other after being obtained via the two methods. In accordance with the relevant norms of fishway designs and gravity similarity criteria, the fishway physical test models were made. Before the installation of the Tai Chi disc and external and internal eight diagrams, a water test and a measurement of the water depth along the center line were conducted. After the installation of Tai Chi disc, the test was divided into two groups to measure the water depth along the center line. The S shaped channel was approximately parallel and vertical to the flow. In each case, Tai Chi disk placement angle was consistent. The above three situations were simulated by numerical calculation. The results showed that they had a same trend. The maximum error was 13.6%, within the allowable range of 15%. Therefore, the calculation model was reliable and can be used to simulate the complex flow field of the pool room. Therefore, the surface velocity, bottom velocity and critical cross section velocity were further analyzed. The results showed that the Tai Chi fishway had significant energy dissipation reduction effect. The shallowest water depth was about twice of that of the corresponding shallowest water depth without the Taichi disk. Average maximum velocity of cross section decreased by about 50%, the flow presented polymorphism, Tai Chi disk’s different positions also made flow change, which can provide more suitable conditions for migratory fish.
flow velocity; models; hydrodynamics; Tai Chi; fishway; mathematical simulation; flow condition
10.11975/j.issn.1002-6819.2018.02.025
TV131
A
1002-6819(2018)-02-0182-07
2017-09-03
2017-11-12
河北省水利科研推廣計(jì)劃(2016-63);河北農(nóng)業(yè)大學(xué)青年學(xué)術(shù)帶頭人基金(2016)
郄志紅,男,河北徐水人,教授,博士生導(dǎo)師,研究方向?yàn)樗そY(jié)構(gòu)優(yōu)化及管理。Email:qiezhihong@163.com
郄志紅,郭麗云,吳鑫淼,冉彥立. 太極式魚道水力特性試驗(yàn)研究及數(shù)值模擬[J]. 農(nóng)業(yè)工程學(xué)報(bào),2018,34(2):182-188. doi:10.11975/j.issn.1002-6819.2018.02.025 http://www.tcsae.org
Qie Zhihong, Guo Liyun, Wu Xinmiao, Ran Yanli. Experimental study and numerical simulation of hydraulic characteristics of Tai Chi fishway[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2018, 34(2): 182-188. (in Chinese with English abstract) doi:10.11975/j.issn.1002-6819.2018.02.025 http://www.tcsae.org