Determination on Effective Influence Radius of Gas Drainage Through Borehole Based on One-dimensional Radial Flow
LI Zi-wen
LIN Bai-quan
GUO Ming-gong
GAO Ya-bin
Abstract：In order to determine the effective influence radius of gas drainage through borehole quickly and accurately,the exponential rela-tionship between drainage quantity of boreholes and drainage time was established based on the mathematical model of one-dimensional ra-dial flow of gas.On the basis of the law of mass conservation and Darcy law,calculation formula of drainage radius was derived and mathe-matical relationship between drainage radius and coal seam parameters and drainage time was established. By using this method,drainage radius of Xinfeng Coal Mine No.25021 Coal Mining Face was calculated.The calculation result was 2.70~3.72 m within 60 days and was similar to the site measurement.Meanwhile,the functional relationship between drainage radius and drainage time was researched.The re-sults showed that with the increase of drainage time,the drainage radius increased gradually.When the drainage time reached to 60 days, the drainage radius reached to 96.46%~98.54% of limit value.After that,the drainage radius increased very slowly.
Keywords：gas drainagedrainage radiusdrainage timedrainage quantity of boreholesradial flow
Publication Date：2014-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：3( 62-64 )