Goaf Gas Control Improvement by Optimizing the Adjacent Roadway Large-Diameter Boreholes

Table 2

Physical parameters of the numerical model.

Symbol	Parameter	Value	Unit
Hl	Height of the fracture zone	40	m
Hk	Height of the caving zone	17	m
Q1	Gas emission of the mining seam	6.49 × 10^−6	kg·(m^3·s)^−1
Q2	Gas emission of the adjacent seam	1.99 × 10^−9	kg·(m^3·s)^−1
Q3	Goaf gas emission amount	1.71 × 10^−7	kg·(m^3·s)^−1