基于CFD技术的超音速喷嘴两相流破碎机制研究

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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.

Key words： spray forming CFD ultrasonic gas atomizer two-phase flows breakup mechanism

Received: 21 November 2017 Published: 12 July 2019

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TF123.112

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	Articles by authors
	ZHU Lingling
	WU Jianjun
	LIU Mingxiang
	SUI Dashan
	CUI Zhenshan

Cite this article:

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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http://pmbjb.csu.edu.cn/EN/ OR http://pmbjb.csu.edu.cn/EN/Y2018/V23/I3/229

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