Natural convection in a non-rectangular porous enclosure

This paper describes a numerical solution procedure to study heat transfer process by two dimensional natural convection phenomena in a non-rectangular enclosure of arbitrary geometry. Momentum transfer in the system is described by an elliptic partial differential equation, which governs the behaviour of the stream function. An algebraic grid generation technique is used to transform the governing equations into a body fitted rectangular co-ordinate system that allows coincidence of all boundary lines with the co-ordinate lines. Numerical solutions of the resulting equations in the computational domain are obtained using an alternating directional implicit method by adding false transient terms. Results from the numerical experiments in the case of a non-rectangular enclosure are obtained that show the magnitude and directions of convection currents and contours of the temperature. The effect of increase in the inclination of the upper boundary is to increase the average Nusselt number.ZusammenfassungDieser Artikel beschreibt den numerischen Lösungsalgorithmus, der für die Untersuchung des Wärmeübergangs mit zweidimensionaler freier Konvektion in nicht-rechtwinkliger Umrandung eingesetzt wird. Der Impulstransport im System wird durch eine elliptische, partielle Differentialgleichung beschrieben. Eine algebraische Netzgenerierungsmethode wird für die Transformation des beschreibenden Differentialgleichungssystems in ein rechtwinkliges Koordinatensystem verwendet. Numerische Lösungen der resultierenden Gleichungen im Berechnungsgebiet wurden durch Verwendung einer speziellen impliziten Methodik ermittelt. Die erhaltenen Ergebnisse werden exemplarisch anhand der Verläufe von Stromlinien und Isothermen graphisch dargestellt.

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