Effect of the Water Injection Pressure on the Permeability of Coal Body

Abstract:

The paper studied the change of permeability of three different coal seam samples at different injection pressure by using the MYS-I type permeability measuring system of coal and rock samples, according to the problem of the coal permeability highly affected during the seepage process, and also researched the water pressure distribution at the pressure of 4 MPa, 8MPa, and 12MPa based on COMSOL Multiphysics. The results show the permeability of coal samples gradually increases with injection pressure increasing and meets a cubic polynomial variation. The injection pressure range obeys a distribution, water pressure gradually decreases with increasing distance from the hole wall at the constant pressure, the flow velocity also reduces. The injection pressure gradient and the effective range gradually increases with injection pressure increasing, the pressure gradient gradually decreases with increasing distance from the hole wall, the maximum coverage radius of water injection pressure range is about 9.5m.

• Periodical: Advanced Materials Research (Volumes 734-737)
• Pages: 551-555
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.734-737.551
• Online since: August 2013
• Authors: Hai Feng Ma*, Chuan Ming Li, Jia Zhuo Li
• Keywords: Effective Range, Gradient, Permeability, Permeability Test System, Water Injection Pressure

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