二维局部受热腔体内电热对流问题模拟和分析  

NUMERICAL STUDY ON TWO-DIMENSIONAL ELECTRO-THERMAL CONVECTION IN A PARTIALLY HEATED CAVITY

作　　者：刘镇涛 肖莉[1] 和琨 汪垒 Liu Zhentao;Xiao Li;He Kun;Wang Lei(School of Mathematics and Physics,China University of Geosciences(Wuhan),Wuhan 430074,China;Center for Mathematical Sciences,China University of Geosciences(Wuhan),Wuhan 430074,China)

机构地区：[1]中国地质大学(武汉)数学与物理学院,武汉430074 [2]中国地质大学(武汉)数学科学中心,武汉430074

出　　处：《力学学报》2021年第9期2477-2492,共16页Chinese Journal of Theoretical and Applied Mechanics

基　　金：国家自然科学基金资助项目(12002320)。

摘　　要：近些年,基于电场的主动强化传热技术因其对特殊环境的良好适用性而获得广泛关注,该问题由于涉及电场、电荷分布场、流场和温度场等多物理场的强烈非线性耦合,目前相关的理论分析和实验研究工作相对较少.本文采用格子Boltzmann方法对二维局部受热腔体内电热对流问题进行了模拟和分析,详细探究了无量纲参数如热瑞利数Ra、电瑞利数T、电极板的长度h和电极板中心到下壁面的距离δ对传热效率的影响,并对电热对流问题中的分岔结构进行了分析.数值结果表明,随着电瑞利数T的增加,传热效率逐渐增强,且电瑞利数T的分岔类型为亚临界型,而热瑞利数Ra表现为超临界型.当电瑞利数T足够大时,库仑力占据绝对优势,浮升力对传热的影响减弱,传热效率的变化不再依赖于热瑞利数Ra.另外,对比不同电极板位置的传热效率时发现电极板处于中间时传热效率最佳,并且电极板长度越短传热效率越高.本文的研究结果拓展了已有二维电热对流模型,可为其他非均匀温度边界电热对流问题的理论分析提供参考.In recent years,the active enhancement of heat transfer with electric field has drawn a wide attention in the field of heat transfer.Since the complex mathematical model as well as the strong nonlinear couplings between multiphysics,the theoretical analysis and experimental studies on this field are relatively few.In this paper,the lattice Boltzmann method is adopted to studied the two-dimensional electro-thermal convection in a partially heated cavity.The effects of dimensionless parameters such as Rayleigh number Ra,electric Rayleigh number T,length of electrode plate h,and the distance from the center of electrode plate to the lower wallδ,on the heat transfer efficiency are investigated,and the bifurcation structure of the electro-thermal convection is also analyzed.Numerical results show that as the number of electric Rayleigh number T increases,the heat transfer efficiency gradually increases,and the bifurcation type for electric Rayleigh number T is usually subcritical.while the bifurcation type for the Rayleigh number Ra is supercritical.In addition,when the electric Rayleigh number T is larger enough,the coulomb force is dominant over the buoyancy force,and the effect of the Rayleigh number Ra on heat transfer coefficient is insignificant.Further,a comparison of the heat transfer efficiency of the various electrode positions shows that the heat transfer efficiency is optimal when the electrode plate is in the middle of the left sidewall,and the smaller the length of the electrode plate,the more efficient of the heat transfer.The results of this article extend the existing two-dimensional electro-thermal convection model,and it can provide a reference for theoretical analysis of other electro-thermal convection problems with non-uniform temperature boundary.

关 键 词：电热对流 局部受热腔体 格子BOLTZMANN方法 

分 类 号：O361.4[理学—流体力学]