Study of the Law of Hydraulically Punched Boreholes on Effective Gas Extraction Radius under Different Coal Outputs

Table 3

Main model parameters.

Parameters	Symbol	Values	Unit
Adsorption constant a	A	32.37	m^3/t
Adsorption constant b	B	0.72	MPa^−1
Elasticity modulus	E	2.74	GPa
Bulk modulus		3.5	GPa
Poisson’s ratio		0.33
Initial gas pressure		1.2	MPa
Standard atmospheric pressure		101	kPa
Initial permeability		4.2 × 10^−17	m^2
Temperature	T	293	K