The Role of Cavitation in Desaturation of Porous Media Under Tension Dani Or and Markus Tuller Dept. of Plants, Soils and Biometeorology, Utah State University

Cavitation During Desaturation of Porous Media Under Tension  Liquid drainage from porous media does not necessarily require air entering the system.  Liquid under tension can be displaced internally, driven by its own vapor pressure.  Evacuation of a pressurized idealized pore (a) occurs in a piston like fashion, whereas in the pore under tension (b) the spherical section evacuates first by formation of a water vapor bubble.

Drainage Characteristic Curve for an Idealized Pore Under Tension vs. Positive Pressure