Air leakage mechanism and hole sealing technology in directional long-drilled perimeter rock-borehole composite fissures: for Gas enrichment in varying coal-seam thickness change areas

• Xuexi ChenNorth China Institute of Science and Technology
• Peixue HanNorth China Institute of Science and Technology
• Jiaying HuNorth China Institute of Science and Technology
• Tao YangNorth China Institute of Science and Technology
• Aitao ZhouChina University of Mining and Technology - Beijing
• Jihong SunChina University of Mining and Technology - Beijing