- Shaughnessy, Edward J. and Van Gilder, James W., Low Rayleigh number conjugate convection in straight inclined fractures in rock,
Numerical Heat Transfer; Part A: Applications, vol. 28 no. 4
pp. 389 - 408 .
(last updated on 2007/04/06)
This investigation explores the natural convection in a water-filled straight inclined fracture in rock subject to a uniform background temperature increasing with depth. The numerical solutions cover aspect ratios from 2 to 50, with Rayleigh numbers of magnitude 1, 10, and 100. The inclination angle ranges from 0° to 90° to the horizontal. The results demonstrate that a straight inclined fracture experiences a gradient-driven convection flow whose strength is strongly dependent on aspect ratio. The flow increases as the fracture angle changes from either purely horizontal or purely vertical, with a maximum at 45°. It is observed that fractures with an aspect ratio as low as 10 exhibit average velocities at the midplane of nearly 90% of the values calculated from the analytical solution for the infinite aspect ratio limit.
Fracture;Rocks;Thermal effects;Thermal gradients;Flow of fluids;Velocity;Calculations;Geometry;Aspect ratio;