Natural Convection of Non-Newtonian Power-Law Fluid Over Axisymmetric and Two-Dimensional Bodies of Arbitrary Shape in a Fluid-Saturated Porous Medium
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摘要: 在一个轴对称、外形任意的多孔介质二维体中,充满了有屈服应力的非Newton幂律流体时,数值分析其自由对流及其传热/传质问题.利用相似变换,将边界层控制方程及其边界条件变换为无量纲形式,然后用有限差分法求解该方程组.所研究的参数为流变常数、浮力比和Lewis数.给出并讨论了典型的速度、温度及浓度曲线.发现屈服应力参数值和非Newton流体的幂律指数对结果有着显著的影响.Abstract: Numerical analysis of free convection coupled heat and mass transfer was presented for nonNewtonian power-law fluids with yield stress flowing over two-dimensional or axisymmetric body of arbitrary shape in a fluid-saturated porous medium. The governing boundary layer equations and boundary conditions were cast into a dimensionless form by similarity transformation and the resulting system of equations was solved by a finite difference method. The parameters studied were the rheological constants, the buoyancy ratio,and the Lewis number. Representative velocity as well as temperature and concentration profiles were presented and discussed. It was found that the result depend strongly on the values of the yield stress parameter,and the power-law index of non-Newtonian fluid.
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Key words:
- non-Newtonian fluid /
- porous medium /
- yield stress
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