The influence of airway resistance on the initial velocity of gas emission from borehole
Abstract：The mathematical model of gas flow in the coal seam,gas flow into the measuring chamber,gas pressure change in the measuring chamber,and gas flow out of the chamber through the airway was established.Using the finite difference method,gas flow around borehole with measuring chamber was measured under dynamic boundary conditions.The variation rule of gas pressure in the measuring chamber and the gas flow quantity in borehole with time was obtained.The influence of airway resistance on initial velocity of gas emission from borehole was analyzed.Results show that when airway length,material and diameter is not the same,the maximum value and appear time of gas flow quantity is different.Airway diameter has great impacts on the value of gas flow in borehole.When the airway resistance is smaller,the gas flow quantity is bigger,and the initial velocity of gas emission from borehole is bigger too.
Keywords：airwayboreholeinitial velocity of gas emissionmeasuring chambergas flow
Publication Date：2011-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)