放电距离对高压脉冲碎煤效能影响研究OA

High-voltage electric pulse liquid-phase discharge fracturing technology is a new coal seam permeability enhancement meth-od based on the liquid electric effect.It forms a three-dimensional fracture network in the coal body through the conversion of electrical energy to mechanical energy,significantly improving the permeability of coal body.By conducting pulse experiments with different dis-charge distances between electrodes and coal samples,and qualitatively and quantitatively studying the permeability and internal damage degree of the coal after the experiment,it was found that:① the discharge distance has a decisive impact on the anti permeability effect of the coal sample-under the condition of a distance of 6 cm,the coal sample(No.3 coal sample)exhibits the best sustained anti per-meability ability,with a balanced development of its fracture network and an increase in permeability of 246％;②under the condition of a 4 cm spacing,although the initial crushing effect of the coal sample is significant(the first 4 discharges contribute 60％of the total in-crease in permeability),the premature occurrence of the"coal fragmentation accumulation effect"leads to a stagnation in permeability growth after 8 discharges;③under the condition of 8 cm spacing,the experimental group had severe energy attenuation and low overall anti reflection efficiency(ultimately improving by＜80％).After 16 discharges,the permeability growth of all experimental groups de-creased to less than 15％of the initial increase,indicating a significant decrease in the efficiency of excessive discharge(＞16 dischar-ges).The study provides key parameter basis for optimizing the high-voltage pulse anti reflection process,and recommends a discharge distance of 6 cm and a discharge frequency range of 8-12 times.