本文選題：離心泵 + 流動誘導噪聲��； 參考：《江蘇大學》2014年博士論文

【摘要】：本文是在國家杰出青年科學基金“離心泵基礎理論和節(jié)能關鍵技術研究”(50825902)、國家科技支撐計劃項目“百萬千瓦級核電離心泵關鍵技術研究”(2011BAF14B04)和江蘇省研究生創(chuàng)新基金“離心泵低噪聲水力設計方法及關鍵技術研究”(CXZZ12-0679)的資助下開展工作。隨著環(huán)境法規(guī)的出臺,用戶對產(chǎn)品的振動噪聲指標提出更高的要求,掌握離心泵噪聲產(chǎn)生機理以及如何在傳統(tǒng)離心泵設計方法的基礎上,通過優(yōu)化幾何參數(shù)提高離心泵的水力效率和降低離心泵的噪聲水平,成為一個重要的研究課題。本文采用機理分析、試驗測試和數(shù)值模擬相結合的方法對離心泵流動噪聲的特性進行研究,旨在建立若干高效率低噪聲離心泵水力設計準則。本文的主要工作和創(chuàng)造性成果有： 1.系統(tǒng)總結分析了離心泵噪聲的分類和產(chǎn)生原因,提出現(xiàn)有的離心泵噪聲測量和評價標準已不能滿足其噪聲評估的需要,離心泵流動誘導噪聲是離心泵機組噪聲測量和評估的關鍵。研究表明離心泵流動誘導噪聲產(chǎn)生的重要因素是其內(nèi)部流場的不穩(wěn)定流體力,來源主要包括：動靜部件間的干涉作用,非設計工況下的葉輪徑向力和不穩(wěn)定流動現(xiàn)象等。 2.搭建了離心泵流動誘導噪聲測試平臺,建立了無源四端網(wǎng)絡法聲學測試模型,試驗研究了離心泵流動噪聲隨運行工況(變流量和變轉(zhuǎn)速)的變化規(guī)律,分析了回流和空化發(fā)生時的流動噪聲特性。通過研究葉輪切割對模型泵流動噪聲聲壓級和空化性能的影響,提出葉輪和隔舌之間的最佳間隙值。結果表明：模型泵在小流量時發(fā)生回流,噪聲聲壓級保持較高的水平,0.6Qd以后,聲壓級隨流量的增大先減小,并在最高效率點達到最小,然后迅速增加；隨著轉(zhuǎn)速的提高,離心泵進、出口流動誘導噪聲聲壓級呈線性上升,離心泵出口的流動噪聲變化要比進口大；隨著空化系數(shù)的減小,流動噪聲的總聲壓級逐漸升高,并在達到極值后降低；模型泵葉輪和隔舌之間的最優(yōu)間隙值為15%,間隙值小于最優(yōu)值時,葉輪切割能明顯降低流動噪聲聲壓級并提升模型泵空化性能；在高效區(qū)運行時,流動噪聲的主頻為葉頻及其倍頻,軸頻及其倍頻也存在極值,回流現(xiàn)象發(fā)生時由于進口預旋造成流道堵塞,流動噪聲的能量往軸頻及超低頻集中,空化現(xiàn)象發(fā)生時,隨著空化系數(shù)的降低,噪聲譜的能量往高頻集中,但低頻區(qū)葉片通過頻率及其倍頻的峰值逐漸減小直至消失。 3.采用結合計算流體力學和計算聲學(CFD/CA)的混合算法對IS65-50-165模型泵的流動誘導噪聲進行求解,并分析了聲振耦合作用對流動誘導噪聲計算的影響。發(fā)現(xiàn)流場求解時,采用Scale Adaptive Simulation (SAS)湍流模擬既能避免對網(wǎng)格和計算資源的過高需求,又能滿足計算聲源信息的需要。研究結果表明：距離隔舌位置近的監(jiān)測點脈動強度較大,表明葉輪和蝸殼隔舌的動靜干涉作用是引起流場脈動的主要原因,隔舌部位是主要的噪聲源；經(jīng)過試驗驗證,在泵高效運行區(qū)間內(nèi)基于CFD/CA的數(shù)值計算求解誤差在3.1%以內(nèi),完全能滿足工程優(yōu)化的需要,其中聲學邊界元法在葉頻及其倍頻噪聲聲壓級求解方面有優(yōu)勢,聲學有限元法雖然建模較復雜,但能直接展現(xiàn)流場體聲源分布并考慮寬頻湍流噪聲的求解,計算結果與實際更加吻合；泵在非高效區(qū)運行時,僅采用偶極子聲源進行聲場計算將不能準確反映模型泵的聲場特性；聲振耦合作用對葉片通過頻率下聲壓級的求解影響很小。 4.以葉頻噪聲聲壓級、揚程、效率和軸功率這四個指標作為判斷標準,首次采用權矩陣方法借助數(shù)值模擬技術對離心泵葉輪進行多目標優(yōu)化設計,得到一組水力模型優(yōu)化方案。通過優(yōu)化葉輪與原型葉輪的試驗對比,發(fā)現(xiàn)該優(yōu)化模型全部達標,驗證了數(shù)值優(yōu)化方法的可行性。通過PIV內(nèi)流場測試發(fā)現(xiàn)：隔舌對流場影響很大,受葉輪和隔舌動靜干涉影響,流場內(nèi)速度的大小、云圖分布都呈現(xiàn)周期性變化,這種干涉作用不但直接作用在隔舌附近流體,還能沿上游傳播影響葉輪進口的流動；高效率低噪聲離心泵葉輪設計的關鍵是選擇合理的葉輪和隔舌間隙,以及減弱葉輪出口的尾流脈動。 5.提出了能較大幅度降低電動離心泵機組輻射噪聲的引射裝置,試驗比較了原型泵、添加正常引射管徑(dy=6mm)和偏大引射管徑(dy=12mm)三種模型泵的性能,并首次數(shù)值計算了包含引射流在內(nèi)的離心泵內(nèi)部流場。研究結果表明：風扇空氣動力學噪聲是離心泵機組運行時產(chǎn)生輻射噪聲中重要的組成部分,采用引射裝置后,輻射噪聲降低約8.3dB; dy=6mm時,模型泵揚程、效率和軸功率的變化均不大,小流量下模型泵的臨界空化余量變小,加設引射管能夠有效減弱回流強度,并降低回流發(fā)生的關鍵流量點；dy=6mm時,由于引射管較大地增加了葉輪實際流量,模型泵的軸功率增幅明顯,而揚程和效率下降很快,同時,由于垂直入射的引射管流太大,造成回流發(fā)生時進口流場的進一步紊亂,抵消了其進口增壓作用,并引起空化性能的惡化。 6.基于法國國立高等工程技術學校的動靜干涉實驗臺,在某導葉式離心泵模型上進行了三孔探針、PIV、導葉葉片靜壓和進口流動噪聲的瞬態(tài)測量等試驗,通過評估導葉壓力恢復能力和分析葉輪上、下游流場的瞬態(tài)特性,對離心泵動靜干涉作用引起的湍流脈動機理進行了研究。研究結果表明：導葉內(nèi)脈動的速度場存在變化明顯的徑向分量,表明模型泵整體等同于聲源向外輻射噪聲,速度場的切向脈動更加強烈表明聲源具有明顯的偶極子特征；按壓力損失情況可以將導葉劃分為無葉片區(qū)域、導葉進口至喉部區(qū)域和喉部下游區(qū)域,導葉靜壓恢復系數(shù)隨流量的減小而變大；導葉設計流量下葉輪出口至導葉喉部區(qū)域的壓力損失最��；小于設計流量時,壓力損失主要集中在導葉無葉片區(qū)域,較大的液流角引起導葉進口的回流,復雜的流動結構造成較大的能量損失,并且隨著流量的逐步減小葉輪進口發(fā)生回流,回流可以延伸到進口管形成失速團,這是小流量情況下湍流噪聲的主要來源；大流量下壓力損失主要發(fā)生在導葉喉部以后區(qū)域,導葉壓力面附近的流動分離是壓力損失和流動噪聲的主要原因,但由于葉輪的阻隔下游的寬頻湍流噪聲不易傳播到上游進口管。
[Abstract]:This article is in the "National Outstanding Youth Science Foundation of basic theory of centrifugal pump and energy-saving key technology research" (50825902), key technology research project "million kilowatt class nuclear ionization heart pump National Science and technology support" (2011BAF14B04) and low noise centrifugal pump hydraulic design method and key technology research and innovation fund of Jiangsu province "graduate" (CXZZ12-0679) to carry out the work of funding. With the environmental regulations, users put forward higher requirements on the vibration and noise index of the product, the generation mechanism of centrifugal pump noise and how to set the basic master meter method in the traditional centrifugal pump, by optimizing the geometric parameters of centrifugal pump to improve the hydraulic efficiency and reduce the noise level of centrifugal pump that has become an important research topic. This paper uses the analysis of the mechanism, characteristics and test method of combining numerical simulation on flow noise of centrifugal pump. The aim of this paper is to establish several hydraulic design criteria for high efficiency and low noise centrifugal pumps. The main work and creative achievements of this paper are as follows:
1. summarizes and analyzes the classification system of centrifugal pump noise and cause, put forward centrifugal pump noise measurement and evaluation of the existing standards can not meet the needs of the noise assessment, the centrifugal pump flow induced noise is the key measurement and assessment of noise of centrifugal pump unit. The results show that the important factors of centrifugal pump flow induced noise is unstable fluid the internal flow field of the source mainly includes: the interaction between static and dynamic components, radial force in non design conditions and unstable flow phenomena.
2. to build a test platform for centrifugal pump flow induced noise, a passive four terminal network method of acoustic test model, experimental study on the flow noise of centrifugal pump with the operating conditions (variable flow and variable speed) changes in the law, analyses the flow noise characteristics of reflux and cavitation occurs. The cutting effect on the flow model of the pump noise level and through the study of the impeller cavitation performance, put forward the optimum gap between the impeller and the casing tongue value. The results show that: the model pump reflux occurs when the flow rate is small, the noise sound pressure level to maintain a high level, after 0.6Qd, the sound pressure level decreases with the increasing of flow rate decreases, and reaches the minimum at the highest efficiency, then increased rapidly with; the improvement of speed, centrifugal pump, outlet flow induced noise level increased linearly, the flow noise changes of centrifugal pump export than import; with the decrease of cavitation coefficient, flow noise The total sound pressure gradually increased, and decreased in the distribution; optimal model clearance between the pump impeller and the tongue of the value of 15%, the gap value is less than the optimal value, the impellers can significantly reduce the sound pressure level of flow noise and enhance the model of pump cavitation performance; in high efficiency operation, frequency of flow noise and frequency for the leaf double shaft frequency and frequency are extreme, reflux phenomenon occurs due to the import of pre swirl caused by clogging, the flow noise energy to shaft frequency and low frequency, cavitation phenomenon occurs, with decreasing cavitation coefficient, the noise spectrum can amount to high concentration, but the peak frequency of blade passing frequency and its harmonics gradually decreased until disappeared.
3. combined with the use of computational fluid dynamics and acoustics (CFD/CA) hybrid algorithm of IS65-50-165 flow model of pump induced noise is solved, and analyzed the influence of acoustic coupling effect on the flow induced noise calculation. It was found that the flow solver, using Scale Adaptive Simulation (SAS) turbulence simulation can avoid excessive demand on the grid and calculation resources, and can satisfy the need of calculating the sound source information. The results show that: the distance between tongue position close to the monitoring point fluctuating intensity, show that the impeller and volute tongue of rotor stator interaction is mainly caused by the flow pulsation, the tongue position is the main noise source; through experiment, in the efficient operation of the pump within the range of CFD/CA based on the numerical calculation error is less than 3.1%, can fully satisfy the needs of engineering optimization, the acoustic boundary element method in frequency and blade frequency noise sound level Has the advantage of solving the acoustic finite element method modeling, although more complex, but can directly show the volume source distribution of flow field and solving the broadband turbulence noise into account, the calculation results agree with the actual work; pump running non efficient area, calculate the sound field will not accurately reflect the characteristics of sound field model of the pump using only the dipole source; the acoustic vibration coupling on the blade by affecting the sound pressure frequency is very small.
With 4. blade frequency noise level, head, shaft power and efficiency of these four indicators as the judgment standard, use technology to perform the multi-objective optimization design of centrifugal pump impeller numerical simulation of weight matrix method is adopted for the first time, a group of hydraulic model optimization. By comparison with the prototype impeller impeller optimization, the optimization model of all the standard, to verify the feasibility of numerical optimization method. Through testing the flow field of PIV found in the tongue: on the flow field is greatly affected by the impeller and tongue movement interference, flow velocity, cloud distribution changes of this period, not only a direct role in the interaction of fluid near the tongue, but also along the upstream propagation effect of impeller inlet flow; high efficiency and low noise design of centrifugal pump impeller is the key to reasonable selection of the impeller and the separation tongue gap, and weaken the impeller wake flow pulsation.
5. proposed can greatly reduce the radiation noise of ejector electric centrifugal pump unit, comparing the prototype pump, add normal ejector diameter (dy=6mm) and large diameter ejector (dy=12mm) performance of the three model pump, and for the first time, numerical calculation of the internal flow field of centrifugal pump includes the entrained flow, research. The results show that the fan aerodynamic noise is generated when the operation of the centrifugal pump unit is an important part of radiated noise, using the jetting device, the noise reduction of about 8.3dB; dy=6mm, head model of pump efficiency and shaft power are not large, small flow pump model the critical cavitation number becomes smaller, add the ejector tube can effectively weaken the strength and reduce the return, the key point of the recirculation flow; dy=6mm, the ejector can greatly increase the actual flow of the impeller, the pump shaft power model increases significantly, while the head and the efficiency At the same time, due to the large flow of the vertical incidence of the ejector tube, the flow field of the inlet is further disturbed when the flow occurs, which counteracts the import boosting effect and causes the deterioration of cavitation performance.
6. French national higher engineering schools movement based on the interference experiment of three hole probe, a guide vane type centrifugal pump model PIV, transient measurement test by static pressure and flow noise import blade, through the pressure recovery and the ability of analysis and evaluation of the guide vanes on the impeller, the transient characteristics of the turbulent flow field downstream. The mechanism of centrifugal pump caused by static interference were studied. The results show that: the pulsation of the guide blades velocity change the radial component obviously, show that the model is equivalent to the whole pump source to radiate noise, the velocity field of the tangential fluctuation more strongly indicate that the dipole sound source has obvious characteristics; according to the pressure loss can be the guide blade divided into the leaf area, the guide vane inlet to the throat area and downstream of the throat area, the guide vane static pressure recovery coefficient with the flow rate decreased; the guide vane design flow Under the impeller outlet guide vane to the throat region of minimal pressure loss; less than the design flow, the pressure loss is mainly concentrated in the guide vane without leaf area, large flow angle caused by the reflux of diffuser inlet, the complex flow structure caused a great loss of energy, and gradually decreased as the flow inlet of the impeller can be reflow, reflux the inlet pipe extends to the formation of stall, this is the case of small flow main source of turbulent noise; high flow pressure loss mainly occurred in the region after the guide vane throat, flow separation near the blade pressure surface is the main cause of pressure loss and flow noise, but due to the wide turbulence noise barrier downstream of the impeller is not easy spread to the upstream of the inlet tube.

【學位授予單位】：江蘇大學
【學位級別】：博士
【學位授予年份】：2014
【分類號】：TH311

【參考文獻】

相關期刊論文 前10條

1 段向陽;王永生;蘇永生;張永祥;;基于聲壓測量的離心泵空化監(jiān)測[J];兵工學報;2010年09期

2 朱曉東,宣征南;碳酸鹽泵振動原因分析及改造[J];撫順石油學院學報;2001年02期

3 魏效玲;薛冰軍;趙強;;基于正交試驗設計的多指標優(yōu)化方法研究[J];河北工程大學學報(自然科學版);2010年03期

4 吳仁榮;船用離心泵的運行振動和減消措施[J];機電設備;2004年06期

5 李意民;;水泵中的回流現(xiàn)象及其對汽蝕的影響[J];流體機械;1995年01期

6 安連鎖,王松嶺,侯軍虎,李春曦;電站鍋爐給水泵振動機理及振動監(jiān)測中的分頻段控制技術[J];流體機械;2000年11期

7 馮濤,劉克,李曉宏,佟小鵬;離心泵水動力噪聲測試系統(tǒng)的研制[J];流體機械;2005年04期

8 王晶;馮濤;劉克;周啟君;;離心泵流動噪聲與其水力學參數(shù)關系的實驗研究[J];流體機械;2007年05期

9 劉瑞韜,徐忠;離心葉輪機械內(nèi)部流動的研究進展[J];力學進展;2003年04期

10 徐朝暉,徐東海,吳玉林,陳乃祥,陳仁;水泵與水輪機空化狀態(tài)監(jiān)測與診斷的研究進展[J];農(nóng)業(yè)機械學報;2003年01期

相關博士學位論文 前2條

1 王勇;離心泵空化及其誘導振動噪聲研究[D];江蘇大學;2011年

2 裴吉;離心泵瞬態(tài)水力激振流固耦合機理及流動非定常強度研究[D];江蘇大學;2013年

，

本文編號：1736165