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Modeling of Work of Filling Granular Filter with Active Cooling
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作者 Alexander D. Rychkov 《Smart Grid and Renewable Energy》 2010年第1期25-31,共7页
The solid propellant gas generators having high gas capacity are widely used for fast pressurization of elastic shells of saving devices of different applications. A typical example of such devices are safety system o... The solid propellant gas generators having high gas capacity are widely used for fast pressurization of elastic shells of saving devices of different applications. A typical example of such devices are safety system of automobile (airbags). After collision of an automobile with an obstacle the combustion products of gas generator fill the shell during 60 – 100 milliseconds. However the temperature of combustion products even of “low-temperature” fuel compositions of gas generators appears not below 1500К and to reduce of its it is necessary to apply a various types of porous and filling granular filters. There are passive and active granular filters. The passive filter can cool of combustion products as a result of absorption of heat only. The active cooling is evaporation of the granule material and in this case takes a place more intensive cooling of combustion products in the filter. The numerical modeling of cooling process of high- temperature combustion products at their movement in bulk of granular filter of active cooling is investigated. As the material of granules was used the carbonate of magnesium. At its heating takes a place process of gasification and formation of a porous slag shell which sublimates at higher temperature. The physical model of such spherical granule can be presented as the central part consisting of the carbonate magnesium surrounded with the porous slag spherical shell through which gaseous products of gasification of the central part are filtered. The problem of distribution of heat in each granule is Stefan problem when at the given temperature on the surface of sphere there is the front of gasification moving inside of the bulk of material. It is assumed that combustion products are the perfect gas moving in the filter. The upwind difference scheme of the second order of the accuracy with TVD properties was applied to calculation of the movement of gas. The results of calculations at various values of key parameters of the active and passive filters allow to draw a conc 展开更多
关键词 MATHEMATICAL Modeling GRANULAR FILTERS heat-and-mass TRANSFER
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Current Status and Prospects of Supercomputing Used for Gas Turbine Engines Design
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作者 Omair Alhatim 《Journal of Energy and Power Engineering》 2016年第2期82-92,共11页
The engineering analysis techniques used for the GTE (gas turbine engines) design are presented, the physical effects, which impact is not currently taken into account are described, further research directions to s... The engineering analysis techniques used for the GTE (gas turbine engines) design are presented, the physical effects, which impact is not currently taken into account are described, further research directions to strengthen core design competencies are identified, the requirements for computing power are formulated. Internal cooling techniques for gas turbine blades have been studied for several decades. The internal cooling techniques of the gas turbine blade includes: jet impingement, rib turbulated cooling, and pin-fin cooling which have been developed to maintain the metal temperature of turbine vane and blades within acceptable limits in this harsh environment. 展开更多
关键词 Engineering analysis GTE design aerodynamics of impeller machines heat-and-mass transfer blade internal cooling.
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建筑墙体热、湿及空气耦合传递 被引量:8
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作者 刘晓燕 贾永英 王志国 《太阳能学报》 EI CAS CSCD 北大核心 2004年第1期13-18,共6页
为了研究建筑墙体的热质耦合传递规律,该文考虑了太阳辐射的影响,建立了在第三类边界条件下建筑墙体非稳态热、湿及空气渗透耦合传递的物理及数学模型,开发了相应的数值模拟计算软件。给出了墙体热、湿及空气耦合传递时各部位模拟计算... 为了研究建筑墙体的热质耦合传递规律,该文考虑了太阳辐射的影响,建立了在第三类边界条件下建筑墙体非稳态热、湿及空气渗透耦合传递的物理及数学模型,开发了相应的数值模拟计算软件。给出了墙体热、湿及空气耦合传递时各部位模拟计算温度随时间的变化曲线及不同使用年限湿容量沿墙体厚度的分布规律,并将墙体的模拟计算结果与现场实测热流及温度进行了对比分析。 展开更多
关键词 墙体 传热传质 耦合 数值 模拟
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关于离散热传导物理模型的探讨 被引量:5
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作者 纪峥 钟万勰 《计算结构力学及其应用》 CSCD 1994年第4期408-414,共7页
本文从热传导离散物理模型上论证了集中质量热容矩阵模型可以在离散点上满足热量守恒定律,采用它就可以避免许多热传导时间积分中的不合理现象。几个算例表明了该模型具有良好的精度。
关键词 有限元 热容矩阵 热量守恒 热传导方程
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金属热还原法制备钛铝中间合金 被引量:5
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作者 宋玉来 豆志河 +2 位作者 张廷安 刘燕 牛丽萍 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2020年第3期1015-1019,共5页
以TiO2为原料,KClO3为发热剂,Al为还原剂和合金化剂,Ca为深度还原剂,通过金属热还原法制备钛铝中间合金,考察了单位质量热效应、造渣剂配比和还原剂加入量及组成对反应过程稳定性、合金成分及收率的关系。研究表明:用Ca和Al作为还原剂时... 以TiO2为原料,KClO3为发热剂,Al为还原剂和合金化剂,Ca为深度还原剂,通过金属热还原法制备钛铝中间合金,考察了单位质量热效应、造渣剂配比和还原剂加入量及组成对反应过程稳定性、合金成分及收率的关系。研究表明:用Ca和Al作为还原剂时,体系绝热温度分别是2426和1806 K,反应制得的钛铝中间合金由Ti Al、Ti3Al和少量的Al2O3夹杂相组成,化学分析合金中Ti、Al、O质量分数分别为58.36%、40.19%和1.41%。 展开更多
关键词 钛铝中间合金 单位质量热效应 绝热温度 金属热还原
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格栅颗粒复合堆积床内流动传热的实验研究 被引量:2
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作者 王晶钰 杨剑 +2 位作者 胡映学 刘衍 王秋旺 《工程热物理学报》 EI CAS CSCD 北大核心 2017年第10期2225-2228,共4页
颗粒有序堆积床相比于颗粒无序堆积床具有压降较小的优点,但在实际操作中,有序堆积床的实现具有一定的难度,本文设计了一种可快速实现有序堆积的新结构,即带有格栅的复合颗粒堆积结构。采用萘升华热质比拟方法对格栅颗粒复合堆积结构中... 颗粒有序堆积床相比于颗粒无序堆积床具有压降较小的优点,但在实际操作中,有序堆积床的实现具有一定的难度,本文设计了一种可快速实现有序堆积的新结构,即带有格栅的复合颗粒堆积结构。采用萘升华热质比拟方法对格栅颗粒复合堆积结构中的颗粒-流体对流传热系数进行了研究。结果表明,格栅复合堆积结构相比于简单立方堆积结构,压降略高,但传热系数也有大幅度提高;而相比于无序结构,在传热系数下降不多的情况下,压降大大减低。格栅颗粒复合堆积结构的综合传热系数最高,可为堆积床的设计提供一种新的思路。 展开更多
关键词 格栅颗粒复合堆积 颗粒有序堆积床 热质比拟 萘升华 对流传热
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横流闭式冷却塔的试验研究 被引量:1
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作者 颜健 刘妮 +2 位作者 欧阳新萍 章立新 李辉 《流体机械》 CSCD 北大核心 2009年第6期53-56,19,共5页
介绍了一种新型的冷却塔——横流闭式冷却塔试验研究,通过试验得到了影响横流闭式冷却塔性能的主要因素,并经过分析得出了这些因素对其性能的影响规律,提出了优化横流闭式冷却塔设计的几点建议。
关键词 冷却塔 传热 传质 喷淋水
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作物覆盖条件下土壤中水热分布的稳态数值比较 被引量:3
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作者 曾海波 刘伟 范爱武 《工程热物理学报》 EI CAS CSCD 北大核心 2002年第4期464-466,共3页
本文应用非饱和多孔介质中传热传质的数学模型,考虑到作物根系和冠层的影响,对稳态情况下圆柱形士壤床中的水热分布进行了数值计算模拟。在不同环境条件下对土壤中的水热分布也进行了模拟计算。同时,在相同环境条件下对有作物覆盖的土... 本文应用非饱和多孔介质中传热传质的数学模型,考虑到作物根系和冠层的影响,对稳态情况下圆柱形士壤床中的水热分布进行了数值计算模拟。在不同环境条件下对土壤中的水热分布也进行了模拟计算。同时,在相同环境条件下对有作物覆盖的土壤床和无作物覆盖的土壤床中的水热分布也进行了模拟比较。文中数值模拟的结果较好地反映了实际情况。 展开更多
关键词 作物覆盖 热质 裸土 数值模拟
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溶液热回收系统研究现状及发展趋势 被引量:1
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作者 王新华 刘泽华 +2 位作者 金雷 李鹏辉 杨晓敏 《煤气与热力》 2012年第10期14-18,共5页
介绍了溶液热回收系统的工作原理与系统结构。综述了除湿剂、塔填料、空气与溶液传热传质、热质回收塔和释放塔的研究现状及发展趋势。
关键词 溶液热回收 溶液除湿 塔填料 传热传质 热质回收塔 热质释放塔
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Local Non-Similarity Solution of Coupled Heat-Mass Transfer of a Flat Plate with Uniform Heat Flux in a Laminar Parallel Flow 被引量:2
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作者 Yuwen Zhang Zhongqi Chen Mingyong Chen(Department of Power Machinery Engineering, Xi’an Jiaotong University, Xi’an 710049, China) 《Journal of Thermal Science》 SCIE EI CAS CSCD 1996年第2期112-116,共5页
The coupled heat and mass transfer problem of gas flow over a UHF flat plate with its wall coated with sublimable substance has been solved by local non-similarity method. Considerations have been given also to the ef... The coupled heat and mass transfer problem of gas flow over a UHF flat plate with its wall coated with sublimable substance has been solved by local non-similarity method. Considerations have been given also to the effect of non-saturation of the sublimable substance in the oncoming flow and the normal injection velocity at the surface. Analytical results are given for local Nusselt and Sherwood numbers at the various locations. 展开更多
关键词 heat-mass transfer uniform heat flux laminar flow
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Convective Heat Transfer Characteristics of the Elliptic Cylinder with Axis Ratio 4∶1 in Crossflow 被引量:2
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作者 齐守良 李庆领 王如竹 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第2期160-163,169,共5页
The heat transfer features around the elliptic cylinder of axis ratio 4∶1 in crossflow were investigated experimentally within a wide range of Reynolds number. By means of heat-mass transfer analogy and the naphthale... The heat transfer features around the elliptic cylinder of axis ratio 4∶1 in crossflow were investigated experimentally within a wide range of Reynolds number. By means of heat-mass transfer analogy and the naphthalene sublimation technique, the local heat transfer distribution and the mean heat transfer coefficient are clarified. The result shows that the mean heat transfer coefficient is higher than that of a circular cylinder in most Reynolds number range regarded, and this superiority turns to be more significant with the increase of flow speed. Moreover, the effect of axis ratio on mean heat transfer coefficient was investigated tentatively. The oil-lampblack technique was employed to enable visualization of the flow pattern around the cylinder and on the cylinder wall. 展开更多
关键词 elliptic cylinder convective heat transfer heat-mass transfer analogy
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Pyrolysis of single large biomass particle: Simulation and experiments 被引量:2
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作者 Kai Wang Huiyan Zhang +1 位作者 Sheng Chu Zhenting Zha 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第1期375-382,共8页
Pyrolysis and heat transfer characteristics of single large biomass particle were investigated using threedimensional unsteady heat transfer model coupled with chemical reactions.The consumption of biomass and the pro... Pyrolysis and heat transfer characteristics of single large biomass particle were investigated using threedimensional unsteady heat transfer model coupled with chemical reactions.The consumption of biomass and the production of products were simulated.Some experiments were designed to provide model parameters for simulation calculations.The simulation was verified by pyrolysis experiments of large biomass particle in a vertical tube furnace.The simulation results show the internal heat and mass transfer law during the pyrolysis of large biomass particle.When the biomass particle diameter is between 10 and 30 mm,for every 5 mm increase in particle diameter,the time required for complete pyrolysis will increase on average by about 50 s.When the pyrolysis temperature is between 673 K and 873 K,a slight decrease in the pyrolysis temperature will cause the time required for the biomass to fully pyrolyze to rise significantly.And the phenomenon is more obvious in the low temperature range.The results indicate that the numerical simulation agrees well with the experimental results. 展开更多
关键词 PYROLYSIS Large biomass particle SIMULATION heat/mass transfer
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建筑墙体热质传递等效耦合扩散模型建立 被引量:2
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作者 贾永英 赵基玉 +1 位作者 魏春艳 朱国伏 《大庆石油学院学报》 CAS 北大核心 2004年第5期52-54,共3页
针对建筑墙体的热传递、湿传递及空气渗透的3个过程,根据多孔介质中多相流体流动描述的体积平均方程,建立了热、湿和空气耦合作用下的墙体热质传递模型,推导了热、湿和空气耦合传递等效扩散方程,分析了建筑墙体热、湿及空气耦合作用下... 针对建筑墙体的热传递、湿传递及空气渗透的3个过程,根据多孔介质中多相流体流动描述的体积平均方程,建立了热、湿和空气耦合作用下的墙体热质传递模型,推导了热、湿和空气耦合传递等效扩散方程,分析了建筑墙体热、湿及空气耦合作用下热质传递过程的主要影响因素———湿容量θL、气压pG和温度T. 展开更多
关键词 墙体 耦合 热质 模型
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Analytical Solution of Coupled Laminar Heat-Mass Transfer in a Tube with Uniform Heat Flux
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作者 Yuwen Zhang (1) Zhongqi Chen (1) 《Journal of Thermal Science》 SCIE EI CAS CSCD 1992年第3期184-188,共5页
Analytical solution is obtained of coupled laminar heat-mass transfer in a tube with uniform heat flux.This corresponds to the case when a layer of sublimable material is coated on the inner surface of a tube with its... Analytical solution is obtained of coupled laminar heat-mass transfer in a tube with uniform heat flux.This corresponds to the case when a layer of sublimable material is coated on the inner surface of a tube with its outer surface heated by uniform heat flux and this coated material will sublime as gas flows throught the tube. 展开更多
关键词 coupled laminar heat-mass transfer uniform heat flux analytical solution.
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孔板波纹填料热源塔换热及阻力特性实验研究
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作者 邹俊杰 梁彩华 +1 位作者 吕珍余 张小松 《建筑热能通风空调》 2020年第1期12-18,共7页
为了解决热源塔按冬季换热需求设计体积偏大的问题,本文对采用小片距大比表面积孔板波纹填料的热源塔进行实验研究,搭建了横流式热源塔实验平台,以乙二醇溶液为循环工质,实验获得了空气流量、温度、含湿量及溶液流量、温度、浓度对孔板... 为了解决热源塔按冬季换热需求设计体积偏大的问题,本文对采用小片距大比表面积孔板波纹填料的热源塔进行实验研究,搭建了横流式热源塔实验平台,以乙二醇溶液为循环工质,实验获得了空气流量、温度、含湿量及溶液流量、温度、浓度对孔板波纹填料热源塔热质传递的影响规律,研究了孔板波纹填料热源塔的阻力特性,并拟合出了传热传质系数及压降的关联式。实验结果表明孔板波纹填料热源塔的传热传质系数主要受风量密度和淋液密度影响,而填料的压降主要受风量密度影响,这为孔板波纹填料热源塔的使用和设计提供了依据。 展开更多
关键词 热源塔 传热传质 孔板波纹填料 阻力特性 拟合
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Numerical Simulation of Multicomponent Alloy Solidification
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作者 Vladimir Pavlovich Ginkin Svetlana Mikhailovna Ganina Andrey Valentinovich Kartavykh 《Journal of Mechanics Engineering and Automation》 2014年第10期828-837,共10页
A non-equilibrium model of multicomponent melt solidification has been developed in which a Stefan problem with two boundaries is solved numerically, the boundaries being between the solid phase and the two-phase tran... A non-equilibrium model of multicomponent melt solidification has been developed in which a Stefan problem with two boundaries is solved numerically, the boundaries being between the solid phase and the two-phase transition zone and between the two-phase transition zone and the liquid phase. The two-phase zone is represented as a porous medium with variable porosity. The additional force resisting the melt flow due to porosity and introduced by analogy with Darcy's law is taken into account. Computer simulation has been performed of the experiment on Sn-20 wt.%Pb binary alloy solidification by the method of downward-directed crystallization along the gravity vector. The paper shows the results of a quasi two-dimensional benchmark experiment on horizontal (i.e., at the right angle to the gravity vector) directional solidification of a binary Sn-3 wt.%Pb alloy. The calculations were done using two crystallization models: the equilibrium model and the non-equilibrium one. It is shown that the non-equilibrium model gives a better description of the thermal field evolution and solute distribution caused by natural convection. 展开更多
关键词 SOLIDIFICATION binary alloy mushy zone MACROSEGREGATION CONVECTION heat-mass transfer modelling comparison withexperimental results.
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强暴雨系统中湿位涡异常的诊断分析 被引量:128
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作者 高守亭 雷霆 +1 位作者 周玉淑 董敏 《应用气象学报》 CSCD 北大核心 2002年第6期662-670,共9页
从动力上推导了热力、质量强迫下的湿位涡方程 ,阐明了在暴雨系统中引起的强降水会造成热力、质量强迫下的湿位涡异常。并用NCEP 1°× 1°的分析资料对 1 999年 6月 2 3日到6月 2 6日引起长江流域暴雨的对流系统进行了湿... 从动力上推导了热力、质量强迫下的湿位涡方程 ,阐明了在暴雨系统中引起的强降水会造成热力、质量强迫下的湿位涡异常。并用NCEP 1°× 1°的分析资料对 1 999年 6月 2 3日到6月 2 6日引起长江流域暴雨的对流系统进行了湿位涡诊断分析 ,分析结果表明湿位涡异常高度主要出现在 70 0~ 5 0 0hPa之间 ,中心最大值可超过 1 .4PVU。从动力和资料诊断两个方面均揭示出湿位涡异常区与强降水区有很好的对应关系。 展开更多
关键词 强暴雨系统 湿位涡 热力强迫 质量强迫 长江流域
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土体冻结过程中的热质迁移研究进展 被引量:46
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作者 何平 程国栋 朱元林 《冰川冻土》 CSCD 北大核心 2001年第1期92-98,共7页
土体的冻胀、融沉问题归根结底是热质迁移问题 ,文章概述了近年来在国际上有关这方面研究的新成果 .总体上讲 ,冻结缘的厚度、分凝冰形成温度以及冰透镜体形成条件等作为热质迁移试验研究的重点受到关注 ,质的迁移研究不仅仅限制在水分... 土体的冻胀、融沉问题归根结底是热质迁移问题 ,文章概述了近年来在国际上有关这方面研究的新成果 .总体上讲 ,冻结缘的厚度、分凝冰形成温度以及冰透镜体形成条件等作为热质迁移试验研究的重点受到关注 ,质的迁移研究不仅仅限制在水分的迁移 ,而且对于矿物质、溶质、气体等的迁移以及对水分迁移的影响都有不同程度的研究 .对于冻胀预报模型 ,已从经验型过渡到依据基本物理、力学、热动力学理论而建立的理论模型 . 展开更多
关键词 冻结过程 热质迁移机理 冻胀预报模型 土体
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计算流体力学技术在粮食储藏中的应用 被引量:60
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作者 王远成 张忠杰 +2 位作者 吴子丹 丁德强 王双凤 《中国粮油学报》 EI CAS CSCD 北大核心 2012年第5期86-91,共6页
计算流体动力学(computational Fluid Dynamics,简称CFD)是通过计算机数值计算和图像显示,对包含有流体流动、热量和质量传递等相关物理现象所做的分析、计算和优化的数值模拟工具。通过CFD技术在储粮通风工程中的应用实例,对CFD技术进... 计算流体动力学(computational Fluid Dynamics,简称CFD)是通过计算机数值计算和图像显示,对包含有流体流动、热量和质量传递等相关物理现象所做的分析、计算和优化的数值模拟工具。通过CFD技术在储粮通风工程中的应用实例,对CFD技术进行了介绍,并对采用CFD技术模拟储粮中的通风过程中流动、热湿传递过程和生态系统的研究现状进行了综述,探讨了采用CFD对储粮中的流动、传热传质过程进行数值模拟的优势以及未来发展趋势。 展开更多
关键词 计算流体力学(CFD) 粮食储藏 流动 传热传质
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多孔介质传热传质研究的现状和展望 被引量:28
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作者 施明恒 虞维平 王补宣 《东南大学学报(自然科学版)》 EI CAS CSCD 1994年第S1期1-7,共7页
本文综述了国内外在多孔介质传热传质研究方面的现状,总结了我国近年来在多孔介质传热传质研究所取得的重要进展,展望了该研究领域中需要深入研究的方向和有关的发展趋势。
关键词 多孔介质 传热传质 迁移现象 渗流
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