NORIA - a finite element computer program for analyzing water, vapor, air, and energy transport in porous media

NORIA is a finite element computer program that solves four nonlinear, parabolic, partial differential equations simultaneously. The four equations describe the transport of water, water vapor, air, and energy through partially saturated porous media. The numerical procedure uses the standard Galerkin finite element method to handle spatial discretization of two-dimensional domains with either planar symmetry or axisymmetry. Time integration is performed by a third-order predictor-corrector scheme that uses error estimates to automatically adjust time-step size so as to maintain uniform local time truncation error throughout the calculation. Thus, the user is not required to select time-step size except at the first time step. Nearly all material properties, such as permeability, can either be set to constant values or can be defined as functions of the dependent and independent variables by user-supplied subroutines. The gas phase is taken to be ideal. This report is intended primarily as a user's manual but also includes discussions of the theory of two-phase transport in porous media and the numerical procedure used in NORIA.