Effects of Chemical Reaction on MHD Micropolar Fluid Flow Past a Vertical Plate in Slip-Flow Regime
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摘要: 对半无限竖直平板为边界的多孔介质,研究了传热、传质对微极流体不稳定滑流的影响,其化学反应是一级均匀的.均匀磁场垂直作用于可以吸收微极流体的多孔表面,吸引速度随着时间而变化.自由流动的速度随着微小扰动而呈指数增大或减小.采用近似方法获得了微极流体的速度、微转动、温度、浓度的表达式,还得到了在不同流体特征和流动条件下,壁面的摩擦系数、耦合应力系数、传热率和传质率.Abstract: Heat and mass transfer effects on unsteady flow of a micropolar fluid through a porous medium bounded by a semi-infinite vertical plate in slip-flow regime was studied, taking into account the homogeneous chemical reaction of first order. A uniform magnetic field acts perpendicular to the porous surface which absorbs the micropolar fluids with a suction velocity varying with time. The free stream velocity follows an exponentially increasing or decreasing small perturbation law. Using approximate method the expression for the velocity microrotation, temperature and concentration were obtained. Also the results of the skin friction coefficient, the couple stress coefficient, the rate of heat and mass transfer at the wall were presented with various values of fluid properties and flow conditions.
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Key words:
- micropolar fluid /
- microrotation /
- chemical reaction /
- slip-flow /
- magnetohydrodynamics /
- heat and mass transfer
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