文档介绍：溴化锂溶液添加表面活性剂的强化吸收微观分析
清华大学孙健付林张世钢侯玮
摘要溴化锂水溶液添加表面活性剂后能显著提高吸收水蒸气过程的传热与传质系数,国内外对此强化过程的研究从20世纪50年代就已经开始,但是迄今为止研究成果多以实验结果为主,尚未有普遍认可的机理理论。国内外的研究者普遍认同“马兰格尼对流”(marangoni convection)的强化作用,但是缺乏对其合理的解释。以往的研究大都基于静态池实验,与实际吸收式制冷机内吸收器的动态吸收过程(如液膜的形成等)相去甚远。而且研究者大都把目光放在研究溴化锂水溶液与水蒸气的汽液界面的强化作用,而忽视了溴化锂水溶液与铜管壁面的固液表面的强化过程。本文从微观的角度对汽液和固液两个强化界面进行了分析,解释了“马兰格尼对流”强化作用产生的原因,理论分析得到的结论也与诸多研究者的实验结果相吻合。
关键词溴化锂;表面活性剂;强化机理;吸收;
孙健,男,1985年1月生,清华大学建筑技术科学系博士研究生,邮箱:stu@
基金项目:1、国家科技支撑计划:电厂循环水余热资源利用技术及装备研究与示范(No: 2007BAB23B01).
Nation Science and Technology Support Plan of Peoples Republic of China (No: 2007BAB23B01).
2、北京市科技计划:利用电厂循环水余热的供热技术研究与应用示范(No: D07040600560701)
The Key Projects of the Beijing Municipal Science and Technology Plan(No: D07040600560701)
Study on mechanism of heat and mass transfer enhancement by adding additive to lithium bromide aqueous solution
Sun Jian★ Fu Lin Zhang Shigang Hou Wei
Abstract The enhancement of heat and mass transfer is significant by adding addictive to lithium bromide aqueous solution, where the water vapor is absorbed. Most of interrelated researches are experimental results from the fifth decade of last century. Marangoni convection which can be observed in many experiments has never been satisfactorily explained. Besides, static absorption is far different from dynamic one. Little study was done on the enhancement between the liquid-solid interfaces by adding add