流经有热源多孔平板并伴有化学反应的传热传质混合对流MHD流动  

Combined Heat and Mass Transfer by Mixed Convection MHD Flow Along a Porous Plate With Chemical Reaction in Presence of Heat Source

作　　者：J·祖额科 S·阿么德 

机构地区：[1]卡塔赫纳综合技术大学流体工程技术系工业工程ETS,卡塔赫纳(木尔西亚),西班牙 [2]戈阿尔帕拉学院数学系流体动力学研究所,阿萨姆邦-783101戈阿尔帕拉,印度

出　　处：《应用数学和力学》2010年第10期1160-1171,共12页Applied Mathematics and Mechanics

摘　　要：对流经无限竖直多孔平板的不可压缩粘性导电流体,稳定的传热传质混合对流MHD流动问题,给出了精确解和数值解.假定均匀磁场横向作用于流动方向,考虑了感应磁场及其能量的粘性和磁性损耗.多孔平板有恒定的吸入速度并均匀地混入流动速度.用摄动技术和数值方法求解控制方程.得到了平板上速度场、温度场、感应磁场、表面摩擦力和传热率的分析表达式.相关参数取不同数值时,用图形表示出问题的数值结果.讨论了从平板到流体的Hartmann数、化学反应参数、磁场的Prandtl数,以及包括速度场、温度场、浓度场和感应磁场等其它参数的影响.可以发现,热源/汇或Eckert数的增大,极大地提高了流体的速度值.x-方向的感应磁场随着Hartmann数、磁场的Prandtl数、热源/汇和粘性耗散的增大而增大.但是,研究表明,随着破坏性化学反应(K>0)的增大,流动速度、流体温度和感应磁场将减小.对色谱分析系统和材料加工的磁场控制,该研究在热离子反应堆模型、电磁感应、磁流体动力学传输现象中得到了应用.An exact and numerical solution to the problem of a steady mixed convective MHD flow of an incompressible viscous electrically conducting fluid past an infinite vertical porous plate with combined heat and mass transfer was presented. A uniform magnetic field was assumed to be applied transversely to the direction of the flow, taking into account the induced magnetic field with viscous and magnetic dissipations of energy. The porous plate was subjec- ted to a constant suction velocity as well as uniform mixed stream velocity. The governing e- quatious were solved by perturbations technique and numerical method. The analytical expressions for the velocity field, temperature field, induced magnetic field, skin-friction and the rate of heat transfer at the plate were obtained. The numerical results were demonstrated graphical- ly for the various values of the parameters involved in the problem. The effects of the Hartmann number, the chemical reaction parameter, the magnetic Prandtl number, and the other parameters involved on the velocity field, temperature field, concentration field and induced magnetic field from the plate to the fluid were discussed. An increase in heat source/sink or Eckert num- ber was found to strongly enhance fluid velocity values. The induced magnetic field along xdirection increases with the increase in Haxtmann number, magnetic Prandtl number, heat source/sink and the viscous dissipation. However, it is found that the flow velocity, fluid temperature, and induced magnetic field decrease with the increase in destructive chemical reaction （K〉0）. Applications of the study arise in thermal plasma reactor modelling, electromagnetic induction, magnetohydrodynamic transport phenomena in chromatographic systems and magnetic field control of materials processing.

关 键 词：MHD 摄动技术 网络模拟法 混合对流 Eckert数 感应磁场 粘性耗散 热源/汇 

分 类 号：O361[理学—流体力学]