Thermal dispersion effects on non-Darcy axisymmetric free convection in a porous medium saturated with a non-Newtonian fluid

• Autorzy: El-Amin M. F.
• Języki publikacji: EN

Abstrakty

EN

A boundary layer analysis is presented to study the effects of thermal dispersion of a non-Newtonian fluid on non-Darcy axisymmetric free convection over a horizontal surface embedded in a porous medium. The Ostwald-de-Waele power-law model is used to characterize the non-Newtonian fluid behavior. The thermal diffusivity coefficient has been assumed to be the sum of the molecular diffusivity and the dynamic diffusivity due to mechanical dispersion. Similarity solutions are obtained when the surface temperature varies as the square root of the radial distance (i.e., the prescribed temperature PT) or when heat flux is constant (i.e., the prescribed heat flux PHF). The effects of the dispersion and non-Darcy parameters as well as the power-law index n on the velocity, temperature, the Nusselt number and the boundary layer thickness are shown on graphs. The numerical values of the rate of heat transfer through the boundary layer in terms of the Nusselt number are entered in a table.

Słowa kluczowe

EN

power-law fluids; porous medium; thermal dispersion; axisymmetric flow; free convection

PL

hydromechanika; porowatość; przepływ osiowy

• Wydawca: Oficyna Wydawnicza Uniwersytetu Zielonogórskiego
• Czasopismo: International Journal of Applied Mechanics and Engineering
• Rocznik: 2005
• Tom: Vol. 10, no 1
• Strony: 77--86
• Opis fizyczny: Bibliogr. 20 poz., tab., wykr.

Twórcy

autor

El-Amin M. F.

• Mathematics Department, Aswan Faculty of Science South Valley University, Aswan 81528, EGYPT

Bibliografia

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