本文關(guān)鍵詞： 節(jié)流控制閥 計(jì)算流體動(dòng)力學(xué) 流場(chǎng)結(jié)構(gòu) 流量特性 閥芯動(dòng)靜態(tài)受力 數(shù)值模擬　出處：《西安石油大學(xué)》2011年碩士論文　論文類型：學(xué)位論文

【摘要】：電纜地層測(cè)試器是通過電纜下放到井下的測(cè)試設(shè)備。節(jié)流控制閥是一種用于地層測(cè)試器采樣模塊系統(tǒng)中控制地層流體流量和壓力大小的一種兩位兩通閥。 該節(jié)流控制閥相比普通節(jié)流閥,體積小,調(diào)節(jié)精度高,其對(duì)壓力的有效調(diào)節(jié)關(guān)系到能否采收到地層真實(shí)流體。其內(nèi)部的水力特性是決定節(jié)流閥對(duì)地層流體樣品高效調(diào)節(jié)的關(guān)鍵因素。同時(shí)閥芯在運(yùn)動(dòng)過程中,節(jié)流閥內(nèi)部流場(chǎng)特性和閥芯受力是節(jié)流閥設(shè)計(jì)應(yīng)用中不可忽略的內(nèi)容。目前,在地層測(cè)試器上,節(jié)流控制閥的內(nèi)部流場(chǎng)尚無人研究。為此,本文運(yùn)用計(jì)算流體力學(xué)的方法對(duì)所設(shè)計(jì)的節(jié)流控制閥模型進(jìn)行數(shù)值模擬,研究閥腔內(nèi)流場(chǎng)結(jié)構(gòu)和閥芯動(dòng)靜態(tài)受力情況。 本文根據(jù)地層測(cè)試器采樣模塊的相關(guān)參數(shù),設(shè)計(jì)出節(jié)流閥,用CAD軟件——UG建立節(jié)流閥流道的三維模型,并用GAMBIT對(duì)模型進(jìn)行網(wǎng)格劃分。通過選用經(jīng)典的基于壓力修正的SIMPLE算法和標(biāo)準(zhǔn)κ-ε兩方程湍流模型,分別在靜止和運(yùn)動(dòng)兩種狀態(tài)下,對(duì)節(jié)流控制閥內(nèi)部流場(chǎng)、流量特性和閥芯受力進(jìn)行數(shù)值仿真研究,優(yōu)化節(jié)流閥的設(shè)計(jì)結(jié)構(gòu)。 利用數(shù)值模擬,對(duì)閥腔內(nèi)的壓力場(chǎng)分布有了清晰的認(rèn)識(shí)：閥腔內(nèi)的壓力在節(jié)流口處降低比較明顯,低壓點(diǎn)出現(xiàn)在閥芯和閥座所形成的間隙內(nèi),最低壓力值為2.5MPa。遠(yuǎn)離節(jié)流口處的壓力比較高。導(dǎo)管處的壓力沿徑向是降低的,而沿軸向變化不大。 通過對(duì)節(jié)流口速度場(chǎng)內(nèi)的射流角研究：射流角隨著開口度的增大而減小,速度值減小。能量耗散位置處于節(jié)流口附近。節(jié)流閥的流量隨著壓力和開度的增大而增大。在一定的開度下,流體的能量耗散和壓降成正相關(guān)。流量系數(shù)與壓降沒有直接關(guān)系,跟節(jié)流閥的開度有很大的關(guān)系,具體與節(jié)流閥本身的結(jié)構(gòu)有關(guān)系。通過模擬計(jì)算,得到節(jié)流閥的流量特性曲線,本閥屬于快開特性。 在上述節(jié)流閥模擬的基礎(chǔ)上,提出節(jié)流閥結(jié)構(gòu)改進(jìn)措施。優(yōu)化結(jié)果表明：改進(jìn)的節(jié)流閥結(jié)構(gòu)流場(chǎng)分布更為均勻,在閥口和導(dǎo)管處的漩渦區(qū)幾乎消除,流體主流在壁面發(fā)生分離程度減小,運(yùn)動(dòng)方向和流道的方向近乎切合,局部阻力較小。流體能量耗散減小了30%,流量系數(shù)提高了25%。 運(yùn)用動(dòng)網(wǎng)格技術(shù)對(duì)節(jié)流控制閥的受力進(jìn)行了分析。在穩(wěn)態(tài)受力研究中,作者推導(dǎo)了節(jié)流控制閥理論穩(wěn)態(tài)液動(dòng)力計(jì)算式,并與數(shù)值模擬結(jié)果對(duì)比,誤差在5%以內(nèi),證明數(shù)值模擬的結(jié)果是可以接受的；節(jié)流閥的穩(wěn)態(tài)液動(dòng)力隨著節(jié)流閥的開度增大而減小,其方向和閥芯關(guān)閉的方向一致。節(jié)流閥閥芯在啟閉兩個(gè)過程中,瞬態(tài)液動(dòng)力的變化規(guī)律是不一樣的。在閥開啟時(shí),瞬態(tài)液動(dòng)力變化拐點(diǎn)隨閥芯移動(dòng)速度增大而靠前,力的數(shù)值也隨著增大。瞬態(tài)液動(dòng)力從負(fù)值范圍先減小,后跨過零點(diǎn)從正值范圍增大。當(dāng)閥芯移動(dòng)速度大于1mm/s時(shí),液動(dòng)力數(shù)值很大,且只在負(fù)值范圍減��；在閥關(guān)閉時(shí),瞬態(tài)液動(dòng)力變化拐點(diǎn)隨移動(dòng)速度的增大而靠前,力的數(shù)值也隨著增大。瞬態(tài)液動(dòng)力僅從正值范圍不斷減小。當(dāng)閥芯移動(dòng)速度過大時(shí),液動(dòng)力數(shù)值也是相當(dāng)大。 通過對(duì)節(jié)流控制閥內(nèi)部流場(chǎng)結(jié)構(gòu)和閥芯受力分析,以此為依據(jù),將會(huì)對(duì)閥優(yōu)化設(shè)計(jì)有一定的理論指導(dǎo)作用。
[Abstract]:The invention relates to a cable formation tester , which is a test equipment which is put underground under a cable , and the throttling control valve is a two - position two - way valve for controlling the flow and the pressure of the formation fluid in the sampling module system of the formation tester . Compared with the conventional throttle valve , the throttle control valve is small in volume and high in regulation precision , and the effective regulation of the pressure is a key factor for determining the effective regulation of the fluid sample of the formation . In this paper , according to the relevant parameters of the sampling module of the formation tester , the throttle valve is designed , the three - dimensional model of the throttle flow passage is established by using the CAD software _ UG , and the mesh division is carried out by using the GAMMA - BIT model . By selecting the classical pressure - corrected SIMPLE algorithm and the standard - k - 蔚 two - equation turbulence model , the internal flow field , the flow characteristic and the force of the valve core are simulated numerically under both static and motion states respectively , and the design structure of the throttle valve is optimized . With the numerical simulation , the pressure field distribution in the valve cavity is clearly recognized : the pressure in the valve cavity is reduced obviously at the orifice , the low pressure point appears in the gap formed by the valve core and the valve seat , and the lowest pressure value is 2.5 MPa . The pressure at the conduit is higher than the pressure at the orifice , and the pressure at the conduit is reduced in the radial direction , and the axial change is not large . The flow coefficient and pressure drop have no direct relation , the flow coefficient and pressure drop have no direct relation , the flow coefficient and pressure drop have no direct relation , and the flow coefficient and pressure drop have a great relationship with the throttle valve , and the flow characteristic curve of the throttle valve is obtained through the simulation calculation . On the basis of the above - mentioned throttle valve simulation , the improvement measures of the throttle structure are put forward . The optimization results show that the flow field distribution of the improved throttle valve structure is more uniform , the vortex area at the valve port and the conduit is almost eliminated , the flow direction of the fluid is close to the direction of the flow channel , the local resistance is small , the dissipation of the fluid energy is reduced by 30 % , and the flow coefficient is increased by 25 % . In the study of steady state stress , the steady - state hydraulic power of the throttle control valve is calculated and compared with the numerical simulation results . The results of the numerical simulation show that the results of the numerical simulation are different . When the valve is opened , the dynamic change of the transient liquid decreases with the increase of the opening degree of the throttle valve . By analyzing the internal flow field structure and the force of the valve core in the throttle control valve , this paper will give some theoretical guidance to the optimization design of the valve .

【學(xué)位授予單位】：西安石油大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2011
【分類號(hào)】：TH137.52

【引證文獻(xiàn)】

相關(guān)博士學(xué)位論文 前1條

1 高紅;溢流閥閥口氣穴與氣穴噪聲的研究[D];浙江大學(xué);2003年

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本文編號(hào)：1496895