撞击流技术在液态物料粉碎细化中的研究

发布时间：2018-03-08 17:17

本文选题：撞击流　切入点：超高压　出处：《上海应用技术学院》2015年硕士论文　论文类型：学位论文

【摘要】：微纳米液体颗粒由于其比表面积和比表面能的显著增大会更易于和其他物质相溶,对改善物质的宏观性能具有良好的促进作用。本文首先分别介绍了超高压撞击流技术、微尺寸管道流动技术和超临界流体技术的研究现状及应用情况,提出一种新的方法即将这三者的优势集于一体,用于制备微纳米液体颗粒。然后分析了液滴的流动过程、液滴撞击壁面的过程和液滴互撞的过程,建立了液滴压力与速度、速度与能量之间的关系,为微纳米颗粒的制备提供了理论基础。在此理论基础之上,运用三维建模软件建立了四种不同结构的超高压微型撞击器的几何模型,并分别研究了相同的高压下不同模型的轴心速度、动压分布以及径向方向上不同位置的速度分布、轴向方向上不同位置的速度分布、壁面剪切力分布。分析结果表明：撞击距离和出口管径是影响撞击器流场的两个重要因素,当撞击器的撞击距离为1m、出口管径为0.5mm时,整个发生器的撞击效果最佳。最后将超高压增压泵、超高压蓄能器和超高压撞击器进行有效地连接,搭建了一套完整的超高压超临界流体撞击流实验平台,并采用油水混合液和果汁作为实验原料对其进行撞击处理。实验结果表明：压力越高,产生的液体颗粒就越细,实验数据再一次验证了超高压微型撞击器的可行性,为微纳米液体颗粒的制备提供了相关原始资料。
[Abstract]:Because of the obvious increase of the specific surface area and specific surface energy, the micro and nano liquid particles will dissolve more easily with other substances, which can promote the improvement of the macroscopic properties of the matter. In this paper, the ultra-high pressure impinging flow technology is introduced respectively. This paper presents a new method for the preparation of micro and nano liquid particles by integrating the advantages of these three technologies into one, and then analyzes the flow process of the droplets. The relationship between droplet pressure and velocity, velocity and energy is established, which provides a theoretical basis for the preparation of nanocrystalline particles. The geometric models of four kinds of ultra-high pressure micro impactor with different structures are established by using 3D modeling software, and the axial velocity, dynamic pressure distribution and velocity distribution in radial direction of different models under the same high pressure are studied respectively. The results show that the impact distance and the outlet diameter are two important factors affecting the flow field of the impactor, when the impactor's impact distance is 1 m and the outlet diameter is 0.5 mm. The impact effect of the whole generator is the best. Finally, the ultra high pressure booster pump, the super high pressure accumulator and the super high pressure impactor are effectively connected, and a complete experimental platform of super high pressure supercritical fluid impinging flow is built. The results show that the higher the pressure, the finer the liquid particles produced, the more feasible the ultra-high pressure micro impactor is. The original data are provided for the preparation of micro-nano-liquid particles.
【学位授予单位】：上海应用技术学院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.1

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