湿空汽撞击流中液滴团聚规律研究

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英文篇名：Study on Droplets Coalescence in Impinging Steam 作者：龚建英 ; 鹿家麒 ; 曾俊雄 ; 王贤勇 ; 高铁瑜 英文作者：GONG Jian-ying;LU Jia-qi;ZENG Jun-xiong;WANG Xian-yong;GAO Tie-yu;MOE Key Laboratory of Thermo-Fluid Science and Engineering, School of Energy and Power Engineering,Xi'an Jiaotong University; 关键词：湿空汽 ; 撞击流 ; 液滴团聚 ; 数值模拟 英文关键词：wet air;;impinging stream;;droplets coalescence;;numerical study 中文刊名：QLJV 英文刊名：Turbine Technology 机构：西安交通大学能动学院热流科学与工程教育部重点实验室; 出版日期：2019-06-25 出版单位：汽轮机技术 年：2019 期：v.61;No.240 语种：中文; 页：QLJV201903002 页数：6 CN：03 ISSN：23-1251/TH 分类号：5-10

摘要

基于湿空汽撞击流中液滴运动理论,搭建实验平台模拟湿蒸汽射流撞击过程,实验结果表明:出口面液滴索特尔平均直径为入口处的3.1到6.1倍,小直径液滴在撞击流中会产生团聚效应。利用数值模拟研究撞击流中液滴团聚机制,数值结果与实验结果误差最大在20%。数值计算结果表明:湍流效应、液滴数量密度和液滴停留时间是影响液滴团聚效应的3个重要因素;随着气流入射角和蒸汽湿度的增加,液滴团聚效应显著增强;针对本文所用撞击装置,当入口流速在2.0m/s～2.5m/s左右时,液滴团聚效应最强。
        Based on the droplets motion theory in impinging steam, this paper build up a rig to simulate the collision process of the wet steam jet flow. Experimental result shows that the SMD(Sauter Mean Diameter) of droplets at the outlet is 3.1 to 6.1 times larger than the SMD of droplets at the inlet. And droplets with small diameters will coalesce in the impinging stream. The numerical results have less than 20% of deviation from experimental results. The numerical results show that turbulent effect, droplets number within unit volume and time of droplets retention are three major factor that effect droplets coalescence. Droplets coalescence is evidently enhanced with the growth of the angle of the air inlet and of the moisture of steam. In the condition of this paper, the droplets coalescence reach maximum when the air inlet velocity is within the range of 2.0 m/s-2.5 m/s.

引文

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