[Retracted] Intelligent Evaluation Method of Pressure Relief Gas Drainage in Goaf Based on IoT Perception

Table 4

Drainage metering data.

Data	7.10	7.11	7.12	7.13	7.14	7.15	7.16
Working face air volume (m^3)	1230	1230	1230	1230	1230	1230	1230
Upper corner gas concentration (%)	0.40	0.38	0.44	0.48	0.36	0.36	0.40
Return airflow gas concentration (%)	0.32	0.30	0.28	0.28	0.30	0.30	0.30
Working face gas concentration (%)	0.18	0.18	0.26	0.30	0.20	0.25	0.26
Drainage temperature (°C)	22.00	22.00	18.00	21.00	19.00	22.00	22.00
Drainage mixed flow (m^3/d)	25.02	24.11	26.28	22.99	22.42	21.93	22.11
Drilling concentration (%)	22.00	13.80	19.50	9.40	8.20	7.10	6.80
Drainage pure flow (m^3/d)	5.40	3.20	4.98	2.04	1.63	1.43	1.57
Drainage negative pressure (kPa)	14.08	14.66	14.65	14.68	14.70	14.12	14.65