A study has been carried out to analyze the combined effects of Soret (thermal-diffusion) and Dufour (diffusion-thermo) coefficients and Schmidt number on natural convection in a partially heated square chamber. The working fluid is water based Al2O3 nanofluid. Energy and concentration equations take into account of Dufour and Soret effects respectively. The governing differential equations are transformed into a set of non-linear coupled ordinary differential equations and solved using similarity analysis with numerical technique using appropriate boundary conditions for various parameters. The numerical solution for the governing nonlinear boundary value problem is based on Penalty Finite Element Method using Galerkin’s weighted residual scheme over the entire range of relevant parameters. The variation of the dimensionless velocity, temperature and concentration profiles are depicted graphically and analyzed in detail. Favorable comparison with previously published work of the problem is obtained. Numerical results for average Nusselt and Sherwood numbers, average temperature and concentration and horizontal and vertical velocities at the middle of the chamber are presented as functions of the governing parameters mentioned above.
soret and dufour coefficients, double-diffusive natural convection, finite element method, water-Al2O3, nanofluid.
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