幂律流体饱和多孔介质通道中的黏性耗散效应

Effects of viscous dissipation on power-law fluid-saturated porous medium in parallel plate channel

针对Darcy-Brinkman-Forchheimer流动模型,分析了幂律型非牛顿流体在填充多孔介质平板通道中强迫对流传热过程充分发展的黏性耗散效应,并比较了三个不同的黏性耗散项Darcy项、Al-Hadhrami项和Forchheimer项对流动传热率的影响。推导出了无量纲轴向流速分布和无量纲温度分布的计算表达式,并在恒热流边界条件下,利用经典Runge-Kutta法进行数值求解。模拟结果表明,布林克曼数Br、达西数Da、综合惯性参数F和幂律指数n等重要参数对无量纲温度分布有着较大的影响,同时发现不同的黏性耗散效应对流动传热特性也有着重要的影响。

Based on Darcy-Brinkman-Forchheimer flow model,the effects of viscous dissipation on power-law fluid saturated porous medium in a parallel plate channel for fully developed forced convection flows were analyzed,and the effects of three different viscous dissipation terms,namely Darcy term,Al-Hadharami term and Forchheimer term on forced convective heat transfer were also compared. The dimensionless expressions of the axial velocity distribution and temperature distribution were deduced and solved numerically by employing the classical Runge-Kutta fourth order scheme subj ect to uniform heat flux. Variations of dimensionless temperature as a function of Brinkman number,Darcy number,Forchheimer inertial parameter and the power-law index were examined and discussed.It is found that the temperature profiles are significantly affected by the relative magnitude of these dimensionless parameters,the results also indicate that the rate of heat transfer is greatly affected by the viscous dissipation effect.