【摘要】：隨著我國油田開發(fā)進入中后期,地層出砂問題嚴重。地層中的砂粒容易被攜帶進井筒,砂粒會造成管線以及設(shè)備的摩擦,導(dǎo)致壽命減短。還有一部分砂粒會不斷沉積在管線底部,久而久之形成砂床,輕則降低了產(chǎn)出液流動性,大大影響油井產(chǎn)量,重則甚至堵塞井眼造成油井停產(chǎn)等工程問題。由于地層出砂現(xiàn)象越來越嚴重,水平井沖砂洗井技術(shù)顯得尤為重要。泡沫發(fā)生器是沖砂洗井的重要設(shè)備,本文對擋板式泡沫發(fā)生器內(nèi)部流動規(guī)律進行研究,其結(jié)構(gòu)簡單,安裝維護方便,氣、液兩相由同一入口泵送進入,擋板阻擋可以改變氣液流動方向,增加氣液碰撞、擠壓的物理過程,提高了發(fā)泡效率,因此在現(xiàn)場實際中得到廣泛應(yīng)用。本文利用計算流體動力學(xué)計算流體動力學(xué)仿真模擬方法,運用SolidWorks軟件建立擋板式泡沫發(fā)生器結(jié)構(gòu)模型,采用FLUENT軟件模擬內(nèi)部流場流動規(guī)律,分析擋板傾斜角度對于泡沫發(fā)生器內(nèi)部氣相體積分布影響,優(yōu)化擋板式泡沫發(fā)生器的結(jié)構(gòu)。文章還研究了入口氣液比等參數(shù)對擋板式泡沫發(fā)生器內(nèi)部流場的影響。數(shù)值模擬結(jié)果得出,隨著擋板角度增大,擋板的擾動作用越強,在擋板后形成的渦流就越大,其消耗氣液混合相動能越大,混合相流速降低,氣流兩相可較早達到平衡狀態(tài)而阻止因界面張力較高發(fā)生氣泡破裂。因而擋板傾角越大,泡沫發(fā)生器混合腔內(nèi)的氣泡含量越高,發(fā)泡效果越好。隨著入口氣相體積含量增大,泡沫發(fā)生器內(nèi)氣液兩相流的速度場分布由差變好再變差,入口氣相體積含量過小或者過大,都較難形成穩(wěn)定的泡沫流。本文將Particle Image Velocimetry(PIV)測試技術(shù)應(yīng)用在擋板式泡沫發(fā)生器內(nèi)部流動規(guī)律研究中,PIV技術(shù)可以清晰地觀測到內(nèi)部流體的流動及泡沫的產(chǎn)生情況,具有準確性、可靠性等優(yōu)點�；趽醢迨脚菽l(fā)生器內(nèi)部流動規(guī)律的分析,建立了發(fā)生器物理模型,研究液相流速以及氣相進口壓力對于其流動規(guī)律的影響。對比數(shù)值模擬結(jié)果與PIV實驗結(jié)果,結(jié)論基本吻合,本文所用方法對擋板式泡沫發(fā)生器氣液兩相流的研究具有可行性,研究成果可有效地為現(xiàn)場沖砂洗井技術(shù)提供理論依據(jù)。
[Abstract]:With the development of oil fields in our country, the problem of formation sand production is serious. Sand particles in formation are easy to be carried into wellbore, which will cause friction of pipeline and equipment and shorten life. Some sand grains will be deposited at the bottom of the pipeline, and sand beds will be formed over time, which will reduce the fluidity of the production fluid, greatly affect the production rate of the well, and even block the well hole to cause the oil well to stop production and other engineering problems. Due to the formation sand production phenomenon more and more serious, horizontal well sand washing technology is particularly important. Foam generator is an important equipment for sand washing well. In this paper, the internal flow law of baffle foam generator is studied. Its structure is simple, installation and maintenance are convenient, gas and liquid are pumped in from the same entrance. The baffle block can change the direction of gas-liquid flow, increase the physical process of gas-liquid collision and extrusion, and improve the foaming efficiency, so it is widely used in the field. In this paper, the structure model of baffle foam generator is established by SolidWorks software, and the flow law of internal flow field is simulated by fluent software. The influence of inclined angle of baffle on gas phase volume distribution in foam generator is analyzed and the structure of baffle foam generator is optimized. The influence of inlet gas-liquid ratio on the flow field of baffle foam generator is also studied. The numerical simulation results show that with the increase of the angle of the baffle, the stronger the disturbance of the baffle is, the greater the eddy current is formed behind the baffle, and the larger the kinetic energy of the gas-liquid mixed phase is consumed, the lower the velocity of the mixed phase is. The gas flow two-phase can reach the equilibrium state earlier and prevent the bubble rupture due to the higher interfacial tension. Therefore, the bigger the dip angle of baffle is, the higher the bubble content in the mixing chamber of foam generator is, and the better the foaming effect is. With the increase of inlet gas volume content, the velocity field distribution of gas-liquid two-phase flow in foam generator becomes better and worse, and the inlet gas phase volume content is too small or too large, it is difficult to form stable foam flow. In this paper, the Particle Image velocimetry (PIV) technique is applied to the study of the internal flow law of the baffle foam generator. The PIV technique can clearly observe the internal fluid flow and the formation of the foam, and has the advantages of accuracy and reliability. Based on the analysis of the internal flow law of the baffle foam generator, the physical model of the generator is established to study the effect of the liquid flow rate and the inlet pressure of the gas phase on the flow law. The results of numerical simulation are in good agreement with those of PIV experiment. The method used in this paper is feasible for the study of gas-liquid two-phase flow in a baffle foam generator. The research results can provide a theoretical basis for the field scouring and sand washing technology.
【學(xué)位授予單位】：東北石油大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：TE935
，

本文編號：2130086