Research Article

Analytical Solutions for Gas-Water Two-Phase Flow in Multiseam Coalbed Methane Production

Table 4

Physical parameters of coal bed.

ParameterValue

Young’s modulus of coal (, GPa)2.735
Poisson’s ratio of coal υ0.25
Coal density (, kg/m3)1500
Seam depth (, m)521.6
Seam thickness (, m)5.8
Porosity 3.51%
Permeability (, mD)0.09
Seam initial pressure (, MPa)6.99
Water viscosity in the ground condition (, Pa·s)
Gas viscosity under standard atmospheric pressure (, Pa·s)
Gas density under standard atmospheric pressure (, kg/m3)0.425
Water density under standard condition (, kg/m3)0.998
Formation volume factor of gas 0.00896
Formation volume factor of water 1.0
The initial gas saturation 0.73
Water saturation 0.27
Solubility 1.3
Relative permeability of gas 0.3466
Relative permeability of water 0.0284
Seam radius (, m)300