本文選題：噴嘴擋板伺服閥 + 射流流場�。� 參考：《哈爾濱工業(yè)大學》2011年碩士論文

【摘要】：由噴嘴擋板結(jié)構(gòu)作為前置級驅(qū)動的電液伺服閥,其射流流場具有流速快、氣穴多、剪切流動強等特征。前置級射流流場的不穩(wěn)定性往往會導致伺服閥工作時產(chǎn)生高頻噪聲,嚴重影響其正常工作特性甚至使用壽命。因此為了改善噴嘴擋板伺服閥的工作性能,建立前置級射流流場的數(shù)學模型并研究其分布規(guī)律是十分必要的。 本文針對噴嘴擋板型伺服閥前置級的射流流場,利用連續(xù)性方程、動量方程、改進型k ?ω湍流模型以及近壁區(qū)計算模型建立了射流流場的數(shù)學模型。利用CAD軟件對噴嘴擋板處的射流流場進行了二維建模,用GAMBIT軟件對模型進行了網(wǎng)格劃分、設置邊界條件等前處理操作,用FLUENT軟件對不同截面、不同尾流區(qū)長度和不同擋板位置的射流流場分別進行了仿真研究,給出了不同條件下速度場和壓力場的分布規(guī)律,總結(jié)了不同流場中出現(xiàn)壓力脈動的條件及其變化關系。搭建了伺服閥前置級射流流場流動特性測試實驗臺,使用數(shù)字顯微鏡和高速攝像機對射流流場進行了可視化實驗,觀察了不同入口壓力下流場的分布情況,使用不同的拍攝速度對流場進行了拍攝,通過觀察射流軌跡的振蕩規(guī)律估算了射流振蕩的周期。 本文在綜述了射流流場流動特性及其壓力脈動研究現(xiàn)狀的基礎上,結(jié)合流體力學基本理論,建立了噴嘴擋板之間射流流場的數(shù)學模型;通過仿真和實驗研究了伺服閥射流流場的流動特性,給出了射流壓力脈動與前置級結(jié)構(gòu)參數(shù)和伺服閥工作條件之間的變化規(guī)律,為進一步研究噴嘴擋板伺服閥前置級射流流場特性以及伺服閥高頻噪聲產(chǎn)生機理提供了一定的理論依據(jù)。
[Abstract]:The jet flow field of the electro-hydraulic servo valve driven by the nozzle baffle structure is characterized by fast velocity, large cavitation and strong shear flow. The instability of the flow field of the front stage jet often leads to high frequency noise when the servo valve works, which seriously affects its normal working characteristics and even its service life. Therefore, in order to improve the performance of the nozzle baffle servo valve, it is necessary to establish the mathematical model of the front stage jet flow field and study its distribution law. In this paper, the mathematical model of jet flow field in front stage of nozzle baffle servo valve is established by using continuity equation, momentum equation, improved k? 蠅 turbulence model and calculation model of near wall region. The jet flow field at the nozzle baffle is modeled by using CAD software. The model is meshed with GAMBIT software, and the pre-processing operation such as setting boundary conditions is carried out. The different sections of the jet flow field are analyzed by FLUENT software. The jet flow field with different wake region length and different baffle position is simulated, the distribution of velocity field and pressure field under different conditions is given, and the conditions of pressure pulsation in different flow field and its variation relationship are summarized. An experimental platform for testing the flow field characteristics of the front stage jet with servo valve is set up. The flow field is visualized by digital microscope and high speed camera, and the distribution of the flow field under different inlet pressure is observed. The jet oscillation period was estimated by observing the oscillation law of the jet trajectory. On the basis of summarizing the current research situation of jet flow field and pressure fluctuation, the mathematical model of jet flow field between nozzle baffles is established based on the basic theory of hydrodynamics. The flow characteristics of the servo valve jet flow field are studied by simulation and experiment. The variation of the jet pressure pulsation, the structural parameters of the front stage and the working conditions of the servo valve are given. It provides a theoretical basis for further studying the characteristics of the jet flow field in the front stage of the nozzle baffle servo valve and the mechanism of the high frequency noise generated by the servo valve.
【學位授予單位】：哈爾濱工業(yè)大學
【學位級別】：碩士
【學位授予年份】：2011
【分類號】：TH134

【參考文獻】

相關期刊論文 前10條

1 雷林;王智祥;孫鵬;聶劍寧;;計算流體力學k-ε二方程湍流模型應用研究[J];船舶工程;2010年03期

2 唐川林,廖振方,張鳳華;自激振蕩的控制在閥類部件上的應用[J];重慶工業(yè)高等專科學校學報;1999年Z1期

3 許曉平;周洲;;多面體網(wǎng)格在CFD中的應用[J];飛行力學;2009年06期

4 楊世綿,趙鳳桐;液壓閥產(chǎn)生噴流噪聲機理初步探討[J];吉林工學院學報;1987年03期

5 周明;;液壓系統(tǒng)振動噪聲與系統(tǒng)設計[J];機械工程師;2006年03期

6 郭威;楊潔明;任錫義;霍鵬飛;;雙噴嘴擋板伺服閥前置放大器的流場分析[J];流體傳動與控制;2010年02期

7 劉敏珊;楊帆;董其伍;謝建;;流體橫掠管束模擬中壁面函數(shù)影響研究[J];熱能動力工程;2010年05期

8 齊鄂榮,黃明海,李煒,李國亞,張昕,吳劍;應用PIV進行二維后向臺階流流動特性的研究(1)二維后向臺階流的旋渦結(jié)構(gòu)的研究[J];水動力學研究與進展(A輯);2004年04期

9 王建軍,李其漢,朱梓根,陸明萬,張雄;自由液面大晃動的流固耦合數(shù)值分析方法研究進展[J];力學季刊;2001年04期

10 徐元利,徐元春,梁興,張進國;FLUENT軟件在圓柱繞流模擬中的應用[J];水利電力機械;2005年01期

，

本文編號：1889978