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就竖直平板嵌入非Darcy多孔介质中,导电流体流过平板时作不稳定的二维磁流体(MHD)双扩散对流,数值研究了Dufour和Soret效应对流动的影响.用Crank-Nicolson型的隐式有限差分法,按三对角矩阵处理,求解无量纲的非线性控制方程.详细地研究了问题中出现的各种参数对不稳定无量纲的速度、温度和浓度曲线的影响.进一步地,给出并分析了表面摩擦因数、Nus-selt数和Sherwood数随时间的变化.研究结果表明,不稳定速度、温度和浓度分布曲线,受Dufour和Soret的影响十分显著.随着Dufour数的增加或者Soret数的减小,表面摩擦因数和Sherwood数都在减小,而Nusselt数在增加.研究发现,当磁场参数增加时,边界层中的速度和温度在减小.
Darcy porous medium is embedded in a vertical plate, and an unstable two-dimensional MHD double diffusive convection is obtained when the conductive fluid flows through the plate. The effects of the Dufour and Soret effects on the flow are numerically studied. Using Crank-Nicolson Implicit finite difference method is used to deal with the non-dimensional nonlinear governing equations according to the tridiagonal matrix, and the effect of various parameters in the problem on unstable dimensionless velocity, temperature and concentration curves is studied in detail , The change of surface friction coefficient, Nusselt number and Sherwood number with time are given and analyzed.The results show that the curves of instability velocity, temperature and concentration are significantly affected by Dufour and Soret.With the increase of Dufour number Increasing or decreasing the Soret number, the surface friction coefficient and the Sherwood number decrease, while the Nusselt number increases.The study found that as the magnetic field parameter increases, the velocity and temperature in the boundary layer decrease.