单液滴形成液膜过程研究  

Process of Liquid Film Formation from Single Droplet

作　　者：刘展位 薄涵亮[1] LIU Zhanwei;BO Hanliang(Institute of Nuclear and New Energy Technology,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学核能与新能源技术研究院,北京100084

出　　处：《原子能科学技术》2024年第12期2478-2484,共7页Atomic Energy Science and Technology

基　　金：中核集团领创科研项目;中核集团“青年英才”项目。

摘　　要：液滴碰壁形成液膜的过程在能源、航天、化工等领域都很常见,其中核能领域的汽水分离设备中有广泛的液滴壁面形成液膜的现象,但目前对液膜的研究相对较少,且缺少对于液滴碰壁形成液膜的机理研究。本文提出一种根据欧拉壁面液膜模型来计算液滴碰壁形成液膜的方法,介绍了液滴形成液膜的计算公式和定义,验证了欧拉壁面液膜模型应用于液膜计算的准确性。最后将方法应用于实际AP1000条件下的液膜计算,分析了不同尺寸的液滴在壁面形成液膜的动态过程,为汽水分离等装置中的壁面液膜计算提供有效的分析工具。研究结果表明,在固定质量流量条件下,随着液滴直径的减小,液膜厚度和液膜速度均会增大。The process of droplet-wall collision forming a liquid film is commonly observed in various fields,including energy,aerospace,and chemical engineering.This phenomenon is particularly prevalent in the nuclear energy sector,where steam-water separation equipment often sees extensive droplet-wall interactions leading to the formation of liquid films.Despite its significance,research on liquid films remains relatively scarce,particularly in terms of understanding the mechanisms behind droplet-wall collision and subsequent film formation.Previous studies have employed both experimental and simulation methods to explore this phenomenon.However,experimental approaches are often constrained by factors such as material properties and temperature,limiting their applicability.Moreover,microscopic numerical methods for studying liquid films are generally inefficient and struggle to provide quantitative analysis of film velocity and thickness.In this paper,a method for calculating the formation of liquid films from droplet-wall collisions based on the Eulerian wall liquid film model was proposed.The calculation formulas and definitions for liquid film formation from droplets of varying sizes were introduced,and the accuracy of applying the Eulerian wall liquid film model to these calculations was validated.The method was subsequently applied to practical AP1000 conditions to analyze the dynamic process of liquid film formation from droplets of different sizes on surfaces.This includes the evolution of a single droplet on a surface,the evolution after multiple droplets collide with the surface,and the evolution following continuous droplet impacts.The study provides an effective analytical tool for calculating wall liquid films in devices such as steam-water separators.The relative error between the liquid film thickness obtained from simulations using the Eulerian wall liquid film model and the actual liquid film thickness is within 8%,validating the method’s accuracy.Additionally,when the mass flow rate of droplets at the

关 键 词：液滴 欧拉壁面 液膜 厚度 速度 

分 类 号：TL334[核科学技术—核技术及应用] TB126[理学—工程力学]