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Journal of Hydrodynamics 2021年第2期33卷 243-258页

作者： Feng Pan Li-zhong Mu Ying He Chao-jie Wang Shi-xiong Zhou School of Energy and Power Engineering Dalian University of TechnologyDalian 116024China

A thermal-hydrodynamic coupling model is used to investigate the interplay between the wall temperature distribution and the bubble departure during the nucleate boiling *** boiling process is modeled as the combination of three subprocesses:the transient heat conduction process in the solid heater,the evaporation of the microlayer underneath the bubble,and the bubble dynamics in the two-phase bulk fluid *** moving bubble interface is captured by the volume of fluid method in the OpenFOAM *** proposed model is validated against the experimental results of the boiling process of the water on an Indium Tin Oxide *** predicted results agree well with related measurements in the *** the validation,the effects of the boiling heat flux on the bubble departure period are *** results show that the bubble departure period decreases with the increase of the applied heat *** heat flux will cause irregularity in the departure periods for successive bubbles due to the influence of the wake flow evoked by the rising ***,the influence of the bubble contact angle on the boiling heat-transfer performance is *** is confirmed that the bubble departure diameter increases with the increase of the contact angle,meanwhile,the average wall temperature decreases with the increase of the contact angle.

关键词： nucleate boiling thermal-hydrodynamic coupling simulation microlayer evaporation contact angle wall temperature distribution

A fractal study for nucleate pool boiling heat transfer of nanofluids

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Science China(Physics,Mechanics & Astronomy) 2010年第1期53卷 30-37页

作者： XIAO BoQi 1 , JIANG GuoPing 2 & CHEN LingXia 1 1 Department of Physics and Electromechanical Engineering, Sanming University, Sanming 365004, China 2 Earthquake Engineering Research Test Center, Guangzhou University, Guangzhou 510405, China Department of Physics and Electromechanical Engineering Sanming University Sanming China Earthquake Engineering Research Test Center Guangzhou University Guangzhou China

In this paper, a fractal model for nucleate pool boiling heat transfer of nanofluids is developed based on the fractal distribution of nanoparticles and nucleation sites on boiling surfaces. The model shows the dependences of the heat flux on nanoparticle size and the nanoparticle volume fraction of the suspension, the fractal dimension of the nanoparticle and nucleation site, temperature of nanofluids and properties of fluids. The fractal model predictions show that the natural convection stage continues relatively longer in the case of nanofluids. The addition of nanoparticles causes a decrease of the pool nucleate boiling heat transfer. The nucleate pool boiling heat transfer coefficient is decreased by increasing particle concentration. An excellent agreement between the proposed model predictions and experimental data is found. The validity of the fractal model for nucleate pool boiling heat transfer is thus verified.

关键词： nanofluid nucleate pool boiling fractal heat transfer

ENHANCEMENT OF nucleate BOILING HEAT TRANSFER WITH ADDITIVES

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Chinese Journal of Chemical Engineering 1992年第1期 1-7页

作者：刘天庆蔡振业林纪方 Institute of Chemical Engineering Dalian University of Technology Dalian 116012 Liaoning

Based on the tests of more than ten different additives, several effective additives are found capable of improving the boiling heat transfer behavior of water pronouncedly. The mechanism of the enhancement of nucleate boiling with additives has been investigated, and the results indicate that one of the important reasons is that the nucleation sites have been increased.

关键词： nucleate boiling heat transfer additive

Concerning The Effect of Surface Material on nucleate Boiling Heat Transfer of R-113

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Journal of Electronics Cooling and Thermal Control 2011年第2期1卷 22-27页

作者： Reza Hosseini Amir Gholaminejad Mahdi Nabil 不详

This paper presents results of an experimental investigation carried out to determine the effects of surface material on nucleate pool boiling heat transfer of refrigerant R113. Experiments were performed on horizontal circular plates of brass, copper and aluminum. The heat transfer coefficient was evaluated by measuring wall superheat and effective heat flux removed by boiling. The experiments were carried out in the heat flux range of 8 to 200 kW/m2. The obtained results have shown significant effect of surface material, with copper providing the highest heat transfer coefficient among the samples, and aluminum the least. There was negligible difference at low heat fluxes, but copper showed 23% better performance at high heat fluxes than aluminum and 18% better than brass.

关键词： Boiling Heat Transfer R-113 nucleate Boiling Surface Material

Bubble growth in superheated liquid based on nonequilibrium thermodynamic theory

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Science China Mathematics 1998年第1期41卷 93-98页

作者：曾丹苓王飞刘朝 Department of Thermal Power Engineering Chongqing University Chongqing China

A mathematical model describing the bubble growth in nucleate boiling is proposed based on non equilibrium thermodynamics. Numerical simulation of the bubble growth process is performed. Some new arguments are suggest... 详细信息

关键词： nucleate boiling bubble growth non equilibrium thermodynamics irreversible process.

Bubble-sweeping mechanisms

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Science China(Technological Sciences) 2003年第3期46卷 225-233页

作者：王昊彭晓峰王补宣李笃中 Department of Thermal Engineering Tsinghua University Department of Chemical Engineering Taiwan University

A series of subcooled boiling experiments was conducted on very small platinum wires having diameters of 0.1 and 0.025 mm. Vapor bubbles were visually observed to sweep back and forth along the wires in the experiments. The dynamic characteristics of bubble-sweeping phe-nomenon are described, and the induced bubble interaction and nonlinear growth are investigated to understand the boiling heat transfer mechanisms. An unsymmetrical temperature model is pro-posed to explain the physical mechanism.

关键词： nucleate boiling, heated wire, bubble, sweeping, unsymmetrical temperature model.

Influence of Laser-Induced Bubble Formation on Laser Chemical Machining

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Journal of Surface Engineered Materials and Advanced Technology 2020年第2期10卷 21-33页

作者： Marcel Simons Tim Radel Raj Shanta Kajsaravally Frank Vollertsen BIAS-Bremer Institut für angewandte Strahltechnik Bremen Germany Department of Communications Engineering Bremen Germany Faculty of Production Engineering-Mechanical Engineering & Process Engineering University of Bremen Bremen Germany

Laser Chemical Machining (LCM) is a non-conventional processing method, which enables very accurate and precise ablation of metallic surfaces. Material ablation results from laser-induced thermal activation of heterogeneous chemical reactions between electrolytes and a metallic surface. However, when processing metallic surfaces with LCM, large fluctuations in ablation quality can occur due to rising bubbles. The for-mation of bubbles during laser chemical machining and their influence on the ablation quality has not been investigated. For a more detailed investigation of the bubbles, ablation experiments on Titanium and Ce-ramic under different thermal process conditions were performed. The experiments were recorded by a high-speed camera. The evaluation of the video sequences was performed using Matlab. The resulting bubbles were analyzed regarding their size and frequency. The results show that boil-ing bubbles formed on both materials during processing. Titanium also produces smaller bubbles, which can be identified as process bubbles ac-cording to their size. Furthermore, it was found that undisturbed laser chemical ablation can be achieved in the presence of a boiling process, since both boiling bubbles and process bubbles were detected during machining within the process window.

关键词： Micro Machining Laser Micro Machining Laser Chemical Removal nucleate Boiling Highspeed Videography

Determination of superheat limit of liquids using fluctuation theory

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Science China Mathematics 1996年第3期39卷 301-308页

作者：曾丹苓敬成君 Department of Thermal Power Engineering Chongqing University Chongqing 630044 China

The theoretical superheat limit of liquids in homogeneous nucleate boiling is determined. A new hypothesis to define the superheat limit is proposed on the basis of the fluctuation theory in statistical thermodynamics. Using Gibbs canonical and grand canonical ensemble formulas, the superheat limit are derived. The numerical results are in good agreement with those in literature.

关键词： superheat limit fluctuation theory Gibbs canonical ensemble grand canonical ensemble homogeneous nucleate boiling.

Modeling a General Equation for Pool Boiling Heat Transfer

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Advances in Chemical Engineering and Science 2013年第4期3卷 294-303页

作者： Mohammed Salah Hameed Abdul Rahman Khan A. A. Mahdi Chemical Engineering Department Higher Colleges of Technology Abu Dhabi United Arab Emirates

It is recognized that the nucleate pool boiling data available in literature are mainly related to four known correlations, each differs from the other by a varying magnitude of constant coefficients, depending on restrictive experimental conditions. The present work is concerned in developing an empirically generalized correlation, which covers the entire range of nucleate boiling with a minimum possible deviation from experimental data. The least squares multiple regression technique is used to evaluate the best coefficient value used in the correlations. An empirical correlation that fits a broader scope of available data has been developed by a non-linear solution technique leading to the following equation: where the coefficients R1 and R3 both represent the effect of surface-liquid combination. They are assessed independently for the used surface material and liquid.

关键词： Pool Boiling nucleate Boiling Linear and Non-Linear Technique Methods Heat Transfer