高翱王强李德军金百刚王凯赫冀成
金属学报
doi:DOI: 10.3724/SP.J.1037.2009.00848
为了克服传统引流砂对钢水的污染, 提出一种采用与钢液成分相同或相近的Fe-C合金代替引流砂, 通过电磁感应加热使其熔化实现自动开浇的电磁引流方法. 利用实验和数值模拟研究了电磁引流装置中水口表面温度随时间的变化规律, 模拟结果与实验结果相吻合. 在此基础上, 考察了感应加热参数(电流强度、电源频率)和感应线圈直径对出钢效果的影响规律, 得出电流强度越大, 电源频率越高, 线圈直径越小, 加热到相同温度所需要的加热时间越短, 越有利于快速加热, 实现顺利出钢的结论. 各因素对出钢时间影响大小的顺序是: 电流强度、电源频率、线圈直径. 找出了可以满足出钢要求的最佳电流强度、电源频率和线圈直径参数, 实验验证了电磁引流技术可以在工艺要求的条件下完成出钢.
关键词:
引流砂
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electromagnetic metallurgy
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clean steel
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numerical simulation
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heat transfer
S. Fedosov Samara State Technical University
,
Galaktionovskaya 141
,
Samara 443010
,
Russia
金属学报(英文版)
"Thermo" computer program is described. It is intended for computation of thermal cycle parameters during surface pulse heating. For example, during laser processing, surface heating owing to grinding, etc. It gives rates of heating, cooling, as well as temperature gradients and cumulative exposure time as function of the CURRENT TEMPERATURE, with the peak temperature at the surface as variable parameter. The indicated parameters are calculated at a surface, close to a surface (at 0.01μm)and for the points at a depth of the body. Demo ver. of the software: http://www. sstu.samara.ru/physics/fedosov/thermo_d. zip
关键词:
heat transfer
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null
,
null
WU Chuansong
,
CAO Zhenning
,
WU Lin Harbin Institute of Technology
,
Harbin
,
China
金属学报(英文版)
A model is established to analyze three-dimensional fluid flow and heat transfer in TICweld pools with full penetration.It considers the deformation of the molten pool surfaceat the condition of full penetrated workpieees,takes the are pressure as the drivingforce of the pool surface deformation,and determines the surface configuration of weldpool based on the dynamic balance of arc pressure,pool gravity and surface tension atdeformed weld pool surface. The SIMPLER algorithm is used to calculate the fluid flowfield and temperature distribution in TIG weld pools of stainless steel workpieces.TIGwelding experiments are made to verify the validity of the model.It shows the calculatedresults by the model are in good agreement with experimental measurements. professor,Dept of Welding Engineering,Harbin Institute of Technology,Harbin 150006,China
关键词:
KEY WORDS TIG weld pool
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null
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null
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null
,
null
W.F. Wu
金属学报(英文版)
A mathematical model has been built to numerically predict the thermal history of thin slab during CSP (compact strip process) rolling. To estimate the temperature distribution in the slab more accurately, the mathematical model combines heat transfer in the slab, in the roll, and at the roll-slab interface during bite. The numerical results agree with on-site running data, which proves the reliability of the mathematical model. The results show that roll chilling has a significant effect on the temperature distribution in the slab.
关键词:
numerical simulation
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数值模拟
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连铸连轧过程
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热过程
D.N.Zou
,
J.Yang
,
Y.L.Huang
,
J.Y.Su
金属学报(英文版)
Based on the continuum model for binary
solid-liquid phase change system, the mathematic model to simulate
the process of laser cladding in situ synthesis
TiCp/Al composite on the surface of aluminum alloy
was formulated. The additive source method was employed to treat
with the heat release of synthetic reaction in powder mixture at
certain temperatures, and also to solve the momentum and heat
transfer caused by the relative movement between laser beam and
the specimen. Two different types of driving forces for flow were
considered in the model, i.e., the buoyancy force and the surface
tension gradient at the laser pool surface. The three-dimensional
transient temperature field simulation program was developed being
based upon the commercial software PHOENICS. The calculated and
observed fusion boundaries were compared and very good agreement
was obtained.
关键词:
numerical simulation
,
null
陈娅琪
,
吴慧英
工程热物理学报
对水力直径分别为407.2 μm(#1)和305.4μm(#2)的硅基梯形截面通道的闭合回路平板振荡热管(FP-CLPHP),以R113为工质进行了一系列实验.微通道热管中可能出现非典型振荡,与典型振荡相比主要区别在于工质返回加热端的驱动力不同.研究了此换热方式的热阻R在不同倾角(0°至90°)不同充液率下(30％至70％),于加热功率2W至10 W的变化情况.以相对空管导热热阻下降作为换热性能提升指标,两热管热阻降低分别为16.5℃/W(65.8％)和8.3℃/W(44.3％),且非典型振荡对充液率的适应性比典型振荡更好.重力对换热有明显提升效果,管径增大也可稍微提升换热.水平工况的换热性能较差,呈现的是工质对加热端长周期的间歇性冲刷.
关键词:
微型振荡热管
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非典型振荡
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可视化
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换热
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平板热管
邝九杰
,
冯上升
,
金东范
,
卢天健
工程热物理学报
本文实验研究了圆管冲击射流下通孔金属泡沫的流动换热特性,测量了10 PPI和30 PPI铜泡沫的平均努塞尔数Nuavg,同时采用烟线法得到冲击射流下铜泡沫的流场可视化图像.结果表明:在较高雷诺数下,存在最优冲击距离使铜泡沫的换热性能最优;在低雷诺数下,通孔铜泡沫的换热性能受冲击距离的影响较小.孔密度为10 PPI的铜泡沫较30 PPI铜泡沫的换热性能提高了约30％.通过流动可视化解释了铜泡沫的换热性能随冲击距离和PPI变化现象.
关键词:
金属泡沫
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圆管冲击射流
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烟线法
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换热
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流场可视化
杨倩鹏
,
田磊
,
常思远
,
史琳
工程热物理学报
换热表面形成的微生物污垢一直是严重影响换热效率和系统安全的重要问题.表面改性是有效抑制微生物污垢生长的措旗,镀银又是表面改性手段中效果较好的一类.当前镀银抑垢研究主要集中在非换热表面,如果将镀银措施引入到换热表面,需要分析抑垢效果、换热变化和经济成本的综合问题.本文通过镀银处理的换热流道实验装置,获得镀银处理后有微生物污垢生长的换热装置的热阻曲线和厚度曲线,对镀银换热表面的抑垢效果、附加热阻、耐久度和经济性进行了全面讨论.结果表明,镀银抑垢效果良好,并且可以优化设计镀银抑垢方案,将经济成本控制在合理范围.
关键词:
微生物污垢
,
镀银
,
抑垢
,
换热
盛强
,
邢玉明
功能材料
doi:10.3969/j.issn.1001-9731.2013.15.009
以框架状泡沫铜为载体,Ba(OH)2·8H2O 为相变储热材料,利用多孔泡沫金属骨架材料良好的吸附性能,制备出泡沫金属复合相变储能材料.采用差示扫描量热法测量Ba(OH)2·8H2O的相变温度和相变潜热,搭建了含泡沫铜和未含泡沫铜相变储能装置的实验台,根据焓-多孔介质模型数值模拟固液相变传热过程.结果表明,泡沫铜的填充不仅增加了相变材料的导热系数,而且缩短了相变材料熔化和凝固时间.数值计算与实验结果吻合良好,验证了该数学模型的可靠性,研究结果对相变储能装置在实际应用中具有一定的指导意义.
关键词:
相变材料
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泡沫铜
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传热
,
数值模拟
