Numerical Simulation on Effective Influence Radius of Hydraulic Flushing Borehole

Abstract:

In this paper, according to the mechanics balance equation, the law of conservation of mass and the relationship between parameters including coal seam permeability, porosity and volume strain, we build a gas-solid coupling model of hydraulic flushing borehole in the coal roadway floor, and use the model to investigate the relationship between ejected coal amount and effective influence radius. The numerical simulation results indicate that the effective radius of hydraulic flushing borehole increase as the drainage time and the ejected coal amount, and the effective influence radius is 5.8m when the ejected coal mass is 1t/m, which indicate the pressure release and permeability enlarging effect is remarkable.

• Periodical: Advanced Materials Research (Volumes 616-618)
• Pages: 1021-1026
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.616-618.1021
• Online since: December 2012
• Authors: Zhi Hui Wen, Jian Ping Wei, Ying Zhen Liu, Hong Tu Zhang
• Keywords: Coupling Equation, Effective Influence Radius, Hydraulic Flushing Borehole, Numerical Simulation

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