摘要
为了提高低渗透性煤体煤层气的开采效率,提出了水中脉冲放电压裂抽采煤层气技术,研究了水中高压电脉冲放电机理和煤体裂隙断裂扩展机理,并应用RFPA-Dynamic进行能量数值模拟计算。研究结果表明:在相同静水压力作用下,随着放电能量的增加,煤体产生裂隙更多,裂隙长度更长,宽度更宽,钻孔周围裂隙密度也更大。裂隙尖端应力随着加载时间和放电能量的增加而增加,裂隙更容易扩展。研究结果可为煤层气的开采提供一定的理论依据。
In order to improve the production efficiency of coal-bed methane with low permeability,we proposed the CBM fracturing and recovery technique with pulsed discharge in water,studied the mechanism of high-voltage electrical pulse discharge in water and the fracture mechanism of coal fractures,and calculated the numerical simulation of energy by RFPA-Dynamic.The results showed that under the same hydrostatic pressure,and with the increase of discharge energy,the fissures increased,the fissure length got longer,the width got wider,and the fissure density around the borehole got larger.The tip stress of the fissure increased with the loading time and the discharge energy,so that the fissures expanded more easily.The research results could provide certain theoretical basis for the exploitation of CBM.
引文
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