Effect of outlet diameter on atomization characteristics and dust reduction performance of X-swirl pressure nozzle

In this study, experimental studies on the atomization characteristics and dust reduction performance of six different X-swirl nozzles with different outlet diameters were performed. The results of the nozzle atomization characteristics shows that, as the diameter of the nozzle increased, the flow rate of the nozzle gradually increased, while the flow coefficient kept decreasing almost linearly. Meanwhile, with the increase of the outlet diameter, the nozzle range and droplet velocity decreased continuously, while atomization angle and droplet size exhibited an increasing trend in general. From results of the dust-reduction experiment, considering the dust-reduction efficiency and water consumption, it is more appropriate to select a nozzle with an outlet diameter of 1.2 mm when the water supply pressure is higher than 4.0 MPa. When the water supply pressure was low, as the diameter of the outlet increased, the dust-reduction efficiencies of the nozzle for both the total dust and the respirable dust increased significantly. Therefore, under low water supply pressure, when the water consumption at the engineering application site is not limited, using a nozzle with a larger outlet diameter can achieve higher dust-reduction efficiency. (C) 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.