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The consequences of local thermal non-equilibrium (LTNE) on both stationary and oscillatory weak nonlinear stability of gravity-driven porous convection in an incompressible fluid-saturated rotating porous layer are investigated. A stability map is drawn in the Darcy–Taylor and scaled Vadasz number plane to demarcate the regions of stationary and oscillatory convection, and thereby, co-dimension-2 points are determined. It is found that the effect of increasing interphase heat transfer coefficient is to enhance the region of stationary convection and decrease the region of oscillatory convection. The complex Ginzburg–Landau equations are derived using the multi-scale method, and pitchfork and Hopf bifurcations occur at stationary and oscillatory critical Darcy–Rayleigh numbers, respectively. The linear and nonlinear oscillatory neutral curves are illustrated, and at the quartic point, the transition from supercritical to subcritical bifurcations is identified for the governing parameters. The impact of LTNE model is to enhance the region of forward bifurcation and post-transient amplitude compared to LTE case. Heat transfer is obtained in terms of Nusselt number for both stationary and oscillatory convection. The region of enhancement in heat flux for oscillatory convection in the smaller scaled Vadasz number domain with increasing Darcy–Taylor number increases with increasing interphase heat transfer coefficient and the porosity-modified conductivity ratio. [ABSTRACT FROM AUTHOR]

This paper describes a finite element simulator for incompressible two-phase flow. This simulator is based on numerical techniques which are novel to the field of reservoir simulation. It uses irregular meshes, discontinuous high-order finite elements for the approximation of saturations (including Riemann solvers and slope limiters), and the mixed-hybrid formulation of mixed finite elements for an efficient and precise approximation of pressures and velocities. Each injection or production well is simulated by a few one-dimensional implicit models arranged to form a macroelement. This simulator is able to handle gravity, capillary pressures, porosity and permeability (both absolute and relative), and heterogeneity. Numerical results are shown which illustrate the capabilities of the code. [ABSTRACT FROM AUTHOR]