共搜索到892条信息，每页显示10条信息，共90页。用时：0小时0分0秒454毫秒
Heat transfer for Marangoni convection over a vapor-liquid interface due to an imposed temperature gradientXiaoyan Sheng1), Liancun Zheng1), and Xinxin Zhang2) 1) School of Applied Science...="ChDivSummary">A similarity analysis for Marangoni convection induced flow over a vapor-liquid interface due to an imposed temperature gradient was carried out. The analysis assumes that the surface......
活性剂法相比,混合气体法不仅可获得深熔深,而且操作方便,易于实现工业化;双层气流法可有效避免混合气体法中电极氧化烧损现象.实验和模拟结果表明:熔池中活性元素O含量变化导致的Marangoni对流方向的变化是TIG焊熔深增加的主要因素,焊接过程中调整液态熔池中活性组元含量可获得大深宽比焊缝.高效率TIG焊接工艺对焊接规范(焊接速度,焊接电流和电极间距)不敏感,有利于在工业生产中推广应用. 关键词:不锈钢； 高效率焊接； 活性元素； 氧； Marangoni对流； 熔池形貌......
words: Marangoni convection; slag film; local corrosion; solid-liquid-gas interface; SiO2-based refractories 1 Introduction The refractory has been extensively applied in high temperature smelting..., SLG) interface [8-10]. Marangoni convection is formed due to the presence of the surface tension gradient which is caused by concentration gradient, temperature gradient or composition change near......
有限厚度的Marangoni对流边界层问题的解析近似解张艳1,2,郑连存1,张欣欣31. 北京科技大学应用科学学院2. 北京建筑工程学院理学院3. 北京科技大学机械工程学院摘 要:讨论了由不同温度介质的界面张力梯度而诱导的有限厚度Marangoni对流的边界层问题.假设界面张力是温度的平方函数,下表面保持恒温,上表面的温度是水平距离的线性函数.通过坐标变换和巧妙引入小参数对速度和温度边界层控制方程组摄动渐进展开,得到了问题的解析近似解.研究了Marangoni数和Prandtl数对速度,温度边界层的影响,对相应的流动特性进行了探讨.关键词:Marangoni对流;边界层;近似解;渐进展开;......
Experimental study on convection heat transfer and air drag in sinter layerPAN Li-sheng(潘利生)1, WEI Xiao-lin(魏小林)1, PENG Yan(彭岩)2, SHI Xiao-bao(时小宝)2, LIU Huai-liang(刘怀亮)2(1. State Key Laboratory of High Temperature Gas Dynamics, Institute of Mechanics,Chinese Academy of Sciences, Beijing 100190, China;2. Citic Heavy Industries Co., Ltd., Luoyang 471039, China)Abstract:Convection heat transfer......
L2(富Cu)液相的运动特征发现,温度梯度和浓度梯度所引起的Marangoni运动促进壳核组织的形成,合金液滴的最终凝固组织由冷却速率,过冷度和Marangoni运动共同决定.如果液滴直径足够小,快速冷却能够抑制液相分离,凝固组织演变为等轴枝晶形态,其相组成为α-Fe固溶体和Cu2FeSn化合物.EDS分析显示,初生α-Fe相在快速凝固过程中发生了显著的溶质截留效应.关键词:Fe-Cu-Sn合金；相分离；快速凝固；Marangoni运动Microstructural evolution mechanism of rapidly solidified ternary Fe62.5Cu27.5Sn10 alloyXIA Zhen-chao, WANG Wei-li, ZHAI Wei, LI Zhi-qiang, WEI Bing-bo(Department of Applied Physics......
微量活性组元氧对焊接熔池Marangoni对流和熔池形貌影响的数值模拟 李依依1,董文超1,陆善平1,李殿中1 (1.中国科学院金属研究所,沈阳,110016) 摘要:针对SUS304不锈钢的定点钨极惰性气体保护焊过程,建立三维瞬态定点热源作用下的焊接熔池数学模型,系统研究了不同氧含量下的熔池温度场,速度场以及熔池形貌演变过程.结果表明:随着熔池中活性组元氧的增加,熔池内的对流模式经历了以外对流为主,内外对流共存到以内对流为主的演变过程,熔池形貌由浅且宽形,"勺"形变成深且窄形.熔池中微量氧直接影响熔池表面张力温度梯度系数,改变熔池表面Marangoni对流模式和熔池最终形貌.当氧含量低于80×10-6时,熔池表面以外向Marangoni对流为主,熔池形貌宽且浅;当氧含量超过120×10-6时,熔池表面以内向Marangoni对流为主,熔池形貌窄且深;当氧含量处于(80-120......
Phase and microstructure selection in directionally solidified peritectic alloys with convection SU Yan-qing(苏彦庆), LI Xin-zhong(李新中), GUO Jing-jie(郭景杰), WU Shi-ping(吴士平),DING Hong-sheng(丁宏生), FU... to investigate the convection effects on phase and microstructure selection in directionally solidified peritectic alloy. Due to the convection effects, the steady-state compositions of one phase......
element, finite volume and finite difference methods [J]. ASME HTD, 1993, 258: 37–47. [50] RUDRAIAH N, BARRON R, VENKATACHALAPPA M, SUBBARAYA C. Effect of a magnetic field on free convection......
J. Cent. South Univ. Technol. (2011) 18: 731-738 DOI: 10.1007/s11771-011-0755-x Characteristics of radiation and convection heat transfer in indirect near-infrared-ray heating chamber CHOI Hoon...: Numerical study was performed to evaluate the characteristics of combined heat transfer of radiation, conduction and convection in indirect near infrared ray (NIR) heating chamber. The effects......
