气液界面对流传质的观测与定量分析

摘要采用光学纹影系统对乙醇和水双组分解吸传质过程的对流结构的界面湍动进行了定性观察和定量分析。建立了一套水平非稳态气液传质设备,试验观测了乙醇和水体系中液相组分向气相传质过程的Marangoni界面对流结构。还通过对传统纹影方法的改进,对乙醇解吸传质过程的浓度(本文用质量分数表示)梯度场进行了定量测量。定量分析表明乙醇和水系统解吸过程中,引发界面湍动的原因是局部较大的表面张力梯度。定量分析的结果很好的解释了伴随Marangoni效应的传质过程的混乱的对流结构,为进一步对界面湍动现象的分析提供了帮助。

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	刘长旭
	曾爱武
	余国琮

关键词： Marangoni 气液传质定量分析纹影系统

Abstract： By utilizing the method of Schlieren system,interfacial turbulence of convective structure in desorption of ethanol from water was observed and quantitatively analyzed.Horizontal unstable gas-liquid mass transfer experimental equipment was set up.The Marangoni interfacial convective structures caused by gas-liquid mass transfer in the interface during the desorption process of ethanol aqueous solution were observed.By employing the improved Schlieren,the concentration gradient of vicinity interface during gas-liquid mass transfer process was obtained. The quantitatively experimental result showed that the reason that induces the Marangoni convection is the local large surface tension gradient along the interface of the gas and liquid.This successfully explains the chaotic flow patterns obtained in gas-liquid mass transfer process accompanied by Marangoni effect and is helpful for the further study on the interfacial turbulence phenomena.

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Received 2008-07-15; published 2008-07-15

引用本文:

刘长旭;曾爱武;余国琮;.气液界面对流传质的观测与定量分析[J]. 化学工业与工程, 2008,25(4): 283-288

LIU Chang-xu,ZENG Ai-wu,YU Guo-cong.Quantitative Analysis and Observation of the Convection near Gas-Liquid Interface[J]. Chemcial Industry and Engineering, 2008,25(4): 283-288

[1]	SHA Yong,CHENG Hong.Optical study on concentrationdriven Rayleigh-Bénard-Marangoni convection[J].Transactions of Tianjin University,2002,8(1):22-26.
[2]	ORELL A,WESTWATER J M.Spontaneous interfacialcellular convection accompanying mass transfer:EthyleneG1ycol-Acetic Acid-Ethyl Acetate[J].AIChE.1962,8(3):350-356
[3]	IMAISHI N,FUJINAWA K.An optical study of interfacialturbulence accompanying chemical absorption[J].InternChem Engng,1980,20:226-232.
[4]	SUCIU D G,SMIGLSCHI O,RUCKENSTEIN E.Someexperiments on the Marangoni effect[J].AIChE,1967,13:1 120-1 124.
[5]	OKHOTSIMSKII A,HOZAWA M.Schlieren visualization ofnatural convection in binary gas-liquid systems[J].ChemEngng Sci,1998,53:2 547-2 573.
[6]	CHR BOYADJIEV.On the mechanism and kinetics of thetransport processes in systems with intensive interphase masstransfer[J].Int J Heat Mass Transfer,2000,53:2 759-2 766.
[7]	SUN Z F,YU K T,WANG S Y,MIAO Y Z.Absorptionand desorption of carbon dioxide into and from organicsolvents:Effects of Rayleigh and Marangoni instability[J].Ind Eng Chem Res.2002,41:1-
[8]	ZHANG S H,WANG Z M,SU Y F.Mass transfer andinterfacial turbulence in a laminar film/Study of transferringtwo solutes separately and simultaneously through liquid-liquid interface[J].Trans I Chem E,1990,68:84-92.
[9]	沙勇,成弘,袁希钢,等.双组分扩散过程Rayleigh-Bénard-Marangoni现象实验研究[J].化工学报,2002,53(9):976-979.
[10]	KLEINE S,VAN ENCKEVORT W J P,DERIX J.A darkfield-type Schlieren microscope for quantitative,in situmapping of solute concentration profiles around growingcrystals[J].Crystal Growth.1997,179:240-248