DOI: 10.11799/ce201710006
Numerical simulation of prefabricated fissures directional hydraulic fracturing in top coal
LV Hua-yong
ZHANG Ya-ning
LIU Fei
Abstract：In order to improve the recovery rate of top coal and reduce the incidence of coal mine safety accidents, directional hydraulic fracturing technology is proposed. Numerical simulation is carried out with RFPA2D -Flow seepage software, for the stabilization process of hydraulic fracturing when the prefabricated fracture angle is 15°. The simulation results show that: stress concentration phenomenon appears at the directional fracture tip, the high stress area transfers to the deep of coal with the fracturing, and the pressure relief zone appears around the drilling and directional fissures; the coal body around drilling and directional cracks is always in the high water pressure area, there is only a small amount of shearing failure in the initial stage of fracturing; when the water pressure is 13MPa, a lot of tensile damage appears on the coal body. At later stage of fracturing, the top of extension fissure begins to transfer and expand, but the transfer angle has little effect on directional fracturing, which indicates favorable directing effect of the prefabricated fissures directional hydraulic fracturing.
Keywords：prefabricated fissuresdirectional hydraulic fracturingfracture extension and expansionpressure relief
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：4( 26-29 )