Sandstone Pore Network — Drainage Invasion

Capillary-controlled invasion percolation: non-wetting fluid displacing wetting fluid in porous rock

Parameters

Saturation: 0%
Rock matrix
Wetting (water)
Non-wetting (oil)
Invasion front
Drainage: non-wetting fluid (oil) injected from left, displacing wetting fluid (water). Invasion order controlled by capillary entry pressure ∝ 1/r_throat. Shows fingering instability and snap-off trapping.