Numerical techniques for simulating groundwater flow in the presence of temperature gradients

Abstract

In this paper we are concerned with situations when vertical temperature gradients in a groundwater aquifer exceed a value determined by the critical Rayleigh number for the onset of thermal convection. In the presence of such temperature gradients, the groundwater flow exists in the form of convective circulation. The variation of water density triggers thermal convection and the variation of dynamic viscosity enhances flow within convective cells. We discuss the mathematical and numerical framework of convective groundwater flow and examine the effects of anisotropic rock permeability and large-scale inhomogeneities on the convective motion.