The experiment and numerical simulation of penetration of coalbed methane upon hydraulic fracturing under high-voltage electric pulse
BAO Xiankai1，2，YANG Dongwei1，DUAN Dongming1，WU Jinwen3
(1. School of Civil Engineering，Inner Mongolia University of Science and Technology，Baotou，Inner Mongolia 014010，China；2. School of Mining Technology，Taiyuan University of Technology，Taiyuan，Shanxi 030024，China；3. School of Science，North University of China，Taiyuan，Shanxi 030051，China)
Abstract：In order to improve the efficiency of methane extraction from coalbed with low permeability，to reveal the effect of high voltage electric pulse on hydraulic fracturing in coal and the development of crack expansions，the laboratory tests of hydraulic fracturing using the high voltage electric pulse on coal samples were carried out under pure hydrostatic(3 MPa) and the same hydraulic pressure(3 MPa)，different discharge voltages(5，10 kV). CT scanning was employed to analyze the initiation，development and distribution of the internal cracks in coal sample. The numerical analysis of the development of fissures and the periphery stress around the fissures under the action of hydraulic electric pulse were carried out. The results show that under the same hydrostatic pressure，the effect of high voltage pulse on hydraulic fracturing of coal is greater than hydrostatic pressure fracturing. The higher the discharge voltage is，the greater the tensile stress in the crack tip is and the crack is easier to produce and develop. The higher the discharge voltage is，the more cracks there are，the earlier the crack initiation，the longer and wider the crack extensions are，and the better the crack fracturing effect. The results of the study proved that the high-voltage pulsed hydraulic fracturing method is effective and feasible.
鲍先凯1，2，杨东伟1，段东明1，武晋文3. 高压电脉冲水力压裂法煤层气增透的试验与数值模拟[J]. 岩石力学与工程学报, 2017, 36(10): 2415-2423.
BAO Xiankai1，2，YANG Dongwei1，DUAN Dongming1，WU Jinwen3. The experiment and numerical simulation of penetration of coalbed methane upon hydraulic fracturing under high-voltage electric pulse. , 2017, 36(10): 2415-2423.
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2017, Vol. 36 
