实验研究和通风实践指出,用于通风除尘的外部吸气罩,由于吸气罩口加挡板,减少了吸风区作用范围,并使等速面向外推移,吸风效果有所改善(图1)。外部吸气罩罩口四周加挡板后,由于减少了无效气流,排风量大约可节省20～30%。 Experimental studies and ventilation practices have pointed out that the external suction hood used for ventilation and dust removal, due to the suction hood mouth and baffles, reduces the scope of the suction area, and the isokinetic surface to the outside, the suction effect has been improved (Figure 1). After adding the baffle around the outside suction hood cover, the amount of air exhausted can be reduced by about 20 to 30% due to the reduced ineffective air flow.