油水分离旋流器油滴运动及其破碎数值模拟

发布时间：2018-04-14 06:08

本文选题：除油旋流器 + 液滴运动轨迹　；参考：《华中科技大学》2015年硕士论文

【摘要】：油水分离水力旋流器是现代石油化工行业中的一种非常重要的物理分离设备,广泛应用于原油开采分离和含油废水处理领域。旋流分离过程中的液滴运动规律是影响其分离效率的重要因素,在液滴运动过程中产生的破碎现象很大程度上降低了油水分离效率,这一现象已经引起旋流分离领域的广泛关注,是液-液旋流分离技术发展过程中必须解决的一个关键问题,具有重要的理论研究意义和实践应用价值。本文采用计算流体动力学FLUENT软件对除油水力旋流器内的油滴运动和油滴破碎现象进行数值模拟研究,主要研究内容和结论如下:通过对比计算流体动力学数值模拟方法中的不同数学模型,选择雷诺应力模型和离散相模型模拟了除油水力旋流器在入口油滴粒径分别为10μm、20μm、30μm、40μm、50μm、60μm时的油滴运动轨迹,研究了油滴粒径、分流比、入口流量等参数对除油分离效率的影响。结果表明,数值模拟结果与实验结果基本吻合,验证了数值模拟的可靠性;油滴的分离区域主要集中在旋流器内的圆柱段、大锥段及小锥段上半部分;随着入口油滴粒径的增大,旋流器分离效率不断增加;随着分流比和入口流量的增大,分离效率都表现为先增大后基本不变;最佳分流比随着入口油滴粒径的减小而增大。运用RNG k-ε湍流模型和流体体积模型对分散相油滴的变形破碎过程进行数值模拟研究,为了模拟除油水力旋流器的内部流场基本特点,选用180°弧形通道简化模型进行模拟分析。系统分析导致油滴破碎的影响因素,研究了油滴粒径、油滴相对滑移速度、油水界面表面张力系数、无量纲参数韦伯数和入口湍流强度对速度边界层内油滴破碎过程的影响。结果表明,韦伯数对油滴破碎起促进作用,韦伯数越大,油滴越容易发生破碎,而入口湍流强度对边界层内的油滴破碎过程基本没有影响。论文的数值模拟研究成果对液-液分离旋流器的操作参数优化和推广应用具有明显的指导意义。
[Abstract]:Oil-water separation hydrocyclone is a very important physical separation equipment in modern petrochemical industry. It is widely used in the field of crude oil extraction separation and oily wastewater treatment.The law of droplet movement in the process of swirl separation is an important factor affecting the separation efficiency. The breakup phenomenon in the process of droplet movement reduces the separation efficiency of oil and water to a great extent.This phenomenon has attracted wide attention in the field of swirl separation and is a key problem that must be solved in the development of liquid-liquid cyclone separation technology. It has important theoretical research significance and practical application value.In this paper, the motion of oil droplets and the phenomenon of oil droplet breakup in deoiling hydrocyclones are numerically simulated by using computational fluid dynamics (FLUENT) software.The main contents and conclusions are as follows: by comparing the different mathematical models in the numerical simulation method of computational fluid dynamics,The Reynolds stress model and the discrete phase model were used to simulate the oil droplet trajectory when the inlet oil droplet diameter was 10 渭 m ~ 20 渭 m ~ 20 渭 m ~ 30 渭 m ~ 40 渭 m ~ 40 渭 m ~ (50 渭 m) ~ (60 渭 m), and the effects of the parameters such as the diameter of the oil droplet, the flow ratio and the inlet flow rate on the oil removal efficiency were studied.The results show that the numerical simulation results are in good agreement with the experimental results, which verifies the reliability of the numerical simulation, and the separation region of the oil droplets is mainly concentrated in the cylinder section, the large cone segment and the upper half part of the small cone section in the cyclone.With the increase of inlet oil droplet size, the separation efficiency of hydrocyclone increases; with the increase of the flow rate and the flow rate, the separation efficiency increases first and then remains unchanged; the optimal separation ratio increases with the decrease of the inlet oil droplet diameter.RNG k- 蔚 turbulence model and fluid volume model are used to simulate the deforming and breaking process of dispersed oil droplets. In order to simulate the basic characteristics of the internal flow field of the deoiling hydrocyclone, the 180 掳arc channel simplified model is used to simulate and analyze.The effects of oil droplet size, relative slip velocity, surface tension coefficient of oil-water interface, dimensionless parameter Weber number and inlet turbulence intensity on the breakup process of oil droplets in the velocity boundary layer were studied.The results show that the Weber number promotes the breakage of oil droplets, and the larger the Weber number is, the easier it is to break the oil droplets, but the turbulent intensity of the inlet has no effect on the breakup process of the oil droplets in the boundary layer.The results of numerical simulation in this paper are of great significance to the optimization of operating parameters of liquid-liquid separation hydrocyclone and its popularization and application.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ051.8

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