Electric field driven flow in natural porous media.

Electric fields were applied to fluid-saturated packed sand beds (0.23+/-0.03 mm average pore diameter), and the effects on the mobility of the water molecules were monitored using stimulated echo (STE) and pulsed field gradient (PFG) experiments.

Observation of electro-osmotic flow echoes in porous media by nuclear magnetic resonance.

A method for assessing the time reversibility of molecular displacements in fluids is presented. The method utilizes pulsed field gradient NMR experiments, in which the flow driving force is inverted during the magnetization lifetime in each measurement cycle. The method is suitable for opaque three-dimensional systems and short displacements, and provides inherent separation between thermal diffusion and displacements driven by externally controlled forces.

NMR T2 distributions and two phase flow simulations from x-ray micro-tomography images of sandstones.

The distribution of fluids in the pore space of a series of sandstones is calculated as a function of capillary pressure using a two phase flow simulation model. The pore space is represented by a system of channels and nodes which are derived from x-ray micro-tomography images of sandstones. The sandstones studied varied in permeability from approximately 40 to 3,000 mD.