MARANGONI EFFECT ON BOILING OF MIXTURES

马兰戈尼效应对混合物沸腾的影响

• 批准号: 09650243
• 负责人: FUJITA Yasunobu
• 金额: $ 2.18万
• 依托单位: KYUSHU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09650243/
• 关键词: MARANGONI CONVECTION; MIXTURE BOILING; CRITICAL HEAT FLUX; MENISCUS; THREE PHASE INTERFACE; EVAPORATION; BUBBLE GROWTH

1. Bubble Growth Analysis Based on Meniscus ModelA numerical simulation scheme was developed to analyze the bubble growth in nucleate boiling and the effect of microlayer evaporation on bubble growth. Heat for the bubble growth was assumed as supplied through the bubble cap by convection and the meniscus by conduction. Transient Navier-Stokes and energy equations were solved using a two-dimensional arbitrary Lagrangian-Eulerian finite element method based on quadrilateral elements. It was revealed that the scheme offers a useful mean to investigate the growth process of bubble with no assumption on the bubble shape and it enables a quantitative description of flow and temperature fields around growing bubbles. It was concluded that the microlayer evaporation dominates bubble growth so that it may be substantial in boiling heat transfer.2. Flow and Heat Transfer in Evaporating MeniscusEvaporation from thin film is very important in heat transfer processes associated with phase change. To make it clear, a steady-state temperature distribution of a meniscus film formed on an inclined and heated cooper plate partially submerged into liquid was measured using a Mach-Zehnder laser interferometer. Water, ethanol, ethylene glycol and their mixtures were used as test fluids to investigate the effect of Marangoni convection on heat transfer in the evaporating meniscus. A numerical analysis was also performed to elucidate heat and flow characteristics in the intrinsic meniscus region and the adjacent evaporating thin film region. It was found the flow direction in the meniscus is reversed, whether mixture is positive or negative. Thus Marangoni convection is expected to play an important role in the evaporation of meniscus film for mixtures.

1.建立了基于弯月面模型的气泡生长分析数值模拟方法，分析了核态沸腾中气泡的生长以及微层蒸发对气泡生长的影响。气泡生长的热量假设为通过气泡帽通过对流提供，通过半月面通过传导提供。采用基于四边形单元的二维任意拉格朗日-欧拉有限元方法求解了非定常的N-S方程和能量方程。结果表明，该方法为研究气泡的生长过程提供了一种有效的手段，不需要假设气泡的形状，并且能够定量描述成长气泡周围的流场和温度场。结果表明，微层蒸发是气泡生长的主要方式，在沸腾换热中可能起到很大的作用。半月板蒸发过程中的流动与传热在相变换热过程中，薄膜的蒸发是非常重要的。利用马赫-曾德尔激光干涉仪测量了部分浸入液体中的倾斜加热库珀平板上形成的弯月面薄膜的稳态温度分布。以水、乙醇、乙二醇及其混合物为实验流体，研究了Marangoni对流对半月板蒸发换热的影响。数值分析了本征弯月面区域和相邻蒸发薄膜区域内的热和流动特性。研究发现，无论是正混合还是负混合，弯月面内的流动方向都是相反的。因此，Marangoni对流有望在混合物的半月面薄膜蒸发过程中发挥重要作用。

项目成果

Qiang BAI: "Critical Heat Flux of Binary Mixtures in Pool Boiling and Its Correlation in Terms of Marangoni Number" INT. J. Refrigeration. 20・8. 616-622 (1997)

白强：“池沸腾中二元混合物的临界热通量及其与马兰戈尼数的相关性”INT。制冷。20・8。

Qiang BAI: "Critical Hrat Flux of Mixtures in Pool Boiling and Its Correlation in Terms on Marangoni Number" Int. J. Refrigeration. 20・8. 616-622 (1997)

白强：“池沸腾中混合物的临界通量及其与马兰戈尼数的相关性”，《制冷》杂志 20・8（1997 年）。

Yasunobu FUJITA: "Heat Transfer and Critical Heat Flux in Pool Boiling of Mixtures" Proc. of 11th Int. Symp. on Transport Phenomena. 1. 330-339 (1998)

Yasunobu FUJITA：“混合物池沸腾中的传热和临界热通量”Proc。

Y.Fujita: "Nucleate Pool Boiling of Binary Mixtures and Heat Transfer Correlation" Proc.4th World Conf.on Experimental Heat Transfer,Fluid Mechanics and Thermodynamics. 2. 681-688 (1997)

Y.Fujita：“二元混合物的核池沸腾和传热相关性”Proc.4th 世界实验传热、流体力学和热力学会议。

Yasunobu FUJITA and Qiang BAI: "Measurement and Analysis of Heat Transfer in Evaporating Meniscus" Proc.of 5th ASME/JSME Thermal Engineering Conference. CD-ROM. 1-8 (1999)

Yasunobu FUJITA和Qiang BAI：“蒸发弯液面传热的测量和分析”第五届ASME/JSME热工程会议论文集。