Transport in Porous Media

, Volume 28, Issue 3, pp 335–372

On Vaporizing Water Flow in Hot Sub-Vertical Rock Fractures

  • Karsten Pruess
Article

DOI: 10.1023/A:1006570702193

Cite this article as:
Pruess, K. Transport in Porous Media (1997) 28: 335. doi:10.1023/A:1006570702193

Abstract

Water injection into unsaturated fractured rock at above-boiling temperatures gives rise to complex fluid flow and heat transfer processes. Examples include water injection into depleted vapor-dominated geothermal reservoirs, and emplacement of heat-generating nuclear wastes in unsaturated fractured rock. We conceptualize fractures as two-dimensional heterogeneous porous media, and use geostatistical techniques to generate synthetic permeability distributions in the fracture plane. Water flow in hot high-angle fractures is simulated numerically, taking into account the combined action of gravity, capillary, and pressure forces, and conductive heat transfer from the wall rocks which gives rise to strong vaporization. In heterogeneous fractures boiling plumes are found to have dendritic shapes, and to be subject to strong lateral flow effects. Fractures with spatially-averaged homogeneous permeabilities tend to give poor approximations for vaporization behavior and liquid migration patterns. Depending on water flow rates, rock temperature, and fracture permeability, liquid water can migrate considerable distances through fractured rock that is at above-boiling temperatures and be only partially vaporized.

heterogeneous fracturespreferential flow pathstwo-phase flowboiling and condensationvapor-dominated geothermal reservoirsnuclear waste disposalnumerical simulation

Copyright information

© Kluwer Academic Publishers 1997

Authors and Affiliations

  • Karsten Pruess
    • 1
  1. 1.Earth Sciences Division, Lawrence Berkeley National LaboratoryUniversity of CaliforniaBerkeleyU.S.A.