Abstract The atomization process of gas-liquid two-phase flows in ultrasonic gas atomizer was analyzed using computational fluid dynamics software. The two kinds of primary-breakup models of liquid metal at different mass flow rates were verified by volume of fluid model, and the effects of atomizing pressure and liquid surface tension on the primary-breakup process were also studied. The simulation results indicate that the transformation of primary-breakup model will occur with decreasing the liquid mass flow rate. When the liquid mass flow rate is 0.053 kg/s, the primary breakup model is melt sheet, but when it is 0.265 kg/s, the primary breakup model is “fountain”. When the atomizing pressure increases from 0.5 MPa to 1.5 MPa, the primary-breakup degree aggravates. However, excessive atomizing pressure will weaken the atomization effect. The smaller-size drop can be formed in the primary-breakup process when the surface tension of liquid metal decreases from 1.2 N/m to 0.4 N/m. Through the following secondary-breakup, more uniform and finer powder particles and high-quality as-spray ingot will be obtained.
ZHU Lingling,WU Jianjun,LIU Mingxiang, et al. A computational fluid dynamics (CFD) research on the atomization mechanism of two-phase flows in ultrasonic gas atomizer[J]. Materials Science and Engineering of Powder Metallurgy, 2018, 23(3): 229-237.
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2018, Vol. 23 
