Nonsimilarity solutions for mixed convection from vertical plate embedded in a porous medium with variable permeability - variable surface heat flux

• Autorzy: Ibrahim F. S. , Omer Gh. M.
• Języki publikacji: EN

Abstrakty

EN

The problem of mixed convection along non-isothermal vertical flat plate embedded in a porous medium with variable permeability is analyzed. Non-similar solutions are obtained for power- law variation of the surface heat flux in the form qw(x) = bxm. The entire mixed convection regime is covered by non-similarity parameter ζ = [1+Rax/Pe3/2x)1/3]-1, from pure forced convection ζ = 1 to pure free convection ζ = 0.0. A finite difference scheme was used to solve the system of transformed governing equations. Velocity and temperature profiles, and local Nusselt numbers are presented. It is found that as ζ decreases from 1 to 0, the thermal boundary thickness increases first and then decreases. But the local Nusselt number in the form Nux(Pe1/2x+Ra1/3x)-1 decreases first and then increases. The variation of permeability increases Nusselt number of all values of ζ.

Słowa kluczowe

EN

vertical plate; mixed convection; porous media; variable permeability; surface heat flux

PL

płaszczyzna pionowa; konwekcja mieszana; materiały porowate; przepuszczalność zmienna; powierzchniowy strumień ciepła

• Wydawca: Wydawnictwo Politechniki Łódzkiej
• Czasopismo: Mechanics and Mechanical Engineering
• Rocznik: 2001
• Tom: Vol. 5, nr 2
• Strony: 155--168
• Opis fizyczny: Bibliogr. 20 poz.

Twórcy

autor

Ibrahim F. S.

• Department of Mathematics. Faculty of Science, Assiut University, Assiut 71516, Egypt.

autor

Omer Gh. M.

• Department of Mathematics. Faculty of Science, Assiut University, Assiut 71516, Egypt.

Bibliografia

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