Pulsed power plasma stimulation-experimental and numerical study on single-pulse test

The recovery of shale resources will not be commercially successful without the key technologies of long lateral wells and hydraulic fracturing. However, large expense and high volume of water consumed during the operation has become a disadvantageous limit when oil price goes below the primary cost of the stimulation process. The motivation for this study comes from an urgent need of more efficient, cost-effective and environmental friendly methods for shale formation stimulation. During the experimental study of Pulsed Power Plasma Stimulation, 2 kJ of electrical energy is stored in capacitor with the discharge voltage sets at 2 kV. A designed system of Exploding Aluminum foil 20"×1" and adaptable electrode is constructed underwater to transfer stored energy into other forms of energy: mechanical energy, electrochemical energy, and electromagnetic energy. The potentials of PPPS technique may be categorized into two parts: a) Mechanically, as an alternative of hydraulic fracturing as a cost-effective and water-saving method for horizontal well stimulation and b) electromagnetically, as an alternative to Microseismic for underground imaging of fracture geometry. Current stage of experiments is focusing on single pulse test. The shock wave, whether it is the result of mechanical energy or the electrochemical energy, exerts direct tremendous dynamic load on the test sample, which causes the initiation of multi-fracture system. The dissertation also gives description of all the experimental set-ups of all aspects and the analysis of all collected data including the pressure measurements and multi-fracture system. During the discharge, the electric current going through the foil could be as high as 40 kA. Strong inductive signal is also captured. This provide strong evidence of the strong magnetic field introduced by changing current (dipole). The radiation pattern of the dipole is studied both analytically and numerically.