Eventos Anais de eventos
COBEM 2017
24th ABCM International Congress of Mechanical Engineering
Convective and absolute instability in a porous medium with inclined temperature gradient, horizontal and vertical throughflow
Submission Author:
Mateus Schuabb , RJ
Co-Authors:
Leonardo Santos de Brito Alves, Mateus Schuabb
Presenter: Mateus Schuabb
doi://10.26678/ABCM.COBEM2017.COB17-1549
Abstract
The theory of linear absolute and convective instabilities are applied in a model of convection in an extended horizontal layer of a saturated porous medium with inclined temperature gradient, horizontal and vertical throughflow. The critical value of vertical Rayleigh number, Rv, is obtained varying the values of horizontal Rayleigh number, Rh, and Péclet number, Qv. The computations are performed by using the shooting method for both analyses, guaranteeing a minimum for the convective analysis and a saddle point for the absolute. For some pairs of values of Rh and Qv in these analyses, there are two modes competing for which is the critical value, then, the marginal curve and the complex wave number plane are plotted to certify that the critical value is the correct. The results of both analyses are compared with the results found in the literature, which in the absolute analysis, there are some different results due this competition of modes. And furthermore, some pairs of values of Rh and Qv are calculated when two pinching point occour simultaneously.
Keywords
Saturated porous layer, Darcy flow, Inclined temperature gradient, Vertical throughflow, Convective and absolute instabilities
