Author(s): Holger Class
Linked Author(s):
Keywords: Three-phase/three-component; Phase state; Saturation vapor pressure; Steam injection; NAPL contamination
Abstract: Steam injection processes in the subsurface with the aim to enhance the remediation of the NAPL-contaminated unsaturated zone by soil vapor extraction can be described by a non-isothermal three-phase/three-component model concept. This work concentrates on the development of a mathematical-numerical model concept that is capable of computing single-phase, two-phase, and three-phase flow processes in one solution domain, including the consideration of mass transfer between the phases. Therefore, a variable substitution algorithm, that is able to adapt the set of primary variables to the respective phase state, was developed. This offers the possibility to the simulator to seize phase appearance and disappearance explicitly. The model concept was verified by comparison of the semianalytical solution of the heatpipe problem with a numerical computation. A comparison of a steam injection experiment in a xylene-contaminated sand-filled column with numerical simulations is given in the last section of this paper.
Year: 1999