Dust Concentration Changing Regularities and Dust Reduction Technology by Spray Negative Pressure in Fully Mechanized Mining Face

Table 2

Measurement data of conventional performance parameters of 1#–16# nozzles under different pressures.

Type	No.	Pressure (MPa)	Atomization angle (°)	Effective range (m)	Flow (L/min)	Type	No.	Pressure (MPa)	Atomization angle (°)	Effective range (m)	Flow (L/min)
A	1#	2	111.7	1.0	3.45	C	9#	2	97.8	2.1	3.41
		4	111.2	1.6	4.12			4	90.3	3.3	4.43
		6	110.8	2.4	5.13			6	83.1	3.7	5.49
		8	110.5	3.7	5.86			8	75.7	4.2	6.67
	2#	2	125.1	1.8	3.92		10#	2	96.5	2.5	4.63
		4	123.6	3.2	5.53			4	91.9	3.5	6.13
		6	122.0	3.7	7.13			6	85.3	4.2	7.31
		8	121.9	4.3	7.67			8	76.0	4.3	7.83
	3#	2	99.5	2.0	4.36	D	11#	2	80.1	2.3	3.67
		4	99.1	2.8	5.98			4	71.6	3.3	4.83
		6	99.0	3.5	7.16			6	71.0	4.1	5.89
		8	98.9	5.2	8.51			8	69.3	4.7	6.83
B	4#	2	67.7	3.2	4.07		12#	2	75.4	3.3	4.42
		4	65.2	3.9	5.75			4	73.1	3.8	5.60
		6	62.6	5.0	6.81			6	68.7	4.7	7.29
		8	59.1	5.1	7.66			8	68.4	5.2	8.72
	5#	2	69.8	3.3	4.63		13#	2	71.7	3.3	6.20
		4	59.3	4.3	6.13			4	66.6	4.3	8.19
		6	56.2	4.8	7.72			6	65.5	5.1	10.27
		8	55.5	5.2	9.13			8	61.8	6.1	11.71
	6#	2	72.1	3.5	6.86	E	14#	2	91.4	2.5	3.77
		4	61.6	4.5	9.00			4	87.6	3.4	5.14
		6	59.9	5.2	10.76			6	79.4	4.5	6.28
		8	59.3	5.7	12.54			8	73.5	5.3	7.05
C	7#	2	94.5	1.2	1.29		15#	2	80.6	3.8	7.39
		4	84.5	1.7	1.57			4	67.6	4.6	10.23
		6	82.9	2.3	2.14			6	65.2	4.9	12.38
		8	75.8	2.7	2.63			8	62.5	6.5	14.76
	8#	2	90.0	1.2	2.29		16#	2	81.4	4.0	10.32
		4	88.3	1.9	2.85			4	75.5	5.2	13.73
		6	83.6	2.8	3.43			6	67.0	7.2	16.96
		8	81.5	3.0	3.94			8	65.9	7.8	19.89