Free surface vortex and associated air entrainment during liquid drainage using two outlets

IF 2.8 2区 工程技术 Q2 ENGINEERING, MECHANICAL
Rahul Kumar Mondal , Lokesh Rohilla , Parmod Kumar
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引用次数: 0

Abstract

Plughole vortex dynamics and the corresponding air entrainment is of paramount importance in various process industries. The present study experimentally investigates plughole vortex induced air entrainment during the drainage of water through two closely spaced outlets from a tank. The discharge from the two outlet tubes has been modulated and the different stages of air entrainment including formation of air lamella, periodic slug bubble pinch-off, and transition into the stable annular flow are observed. The transition between the slug bubble pinch-off and the stable annular flow has been modelled by balancing the local dynamic pressure of the fluid and the Laplacian pressure jump across the gas-liquid interface. The balance yields the ratio of critical height, Hc and radius of the stable air neck, rm as Hc/rm30.68Bo-0.904fD,re-0.210, with the Bond number, Bo=ΔρgD2/σ and the geometric parameter, fD,re=1-2reD2.

使用两个出口进行液体排放时的自由表面涡流和相关空气夹带
在各种加工工业中,堵孔涡流动力学和相应的空气夹带至关重要。本研究通过实验研究了水箱中两个间隔较近的出水口排水时塞孔涡流引起的空气夹带。对两个出水管的排水量进行了调制,并观察了空气夹带的不同阶段,包括空气薄片的形成、周期性蛞蝓气泡夹断以及向稳定环形流的过渡。通过平衡流体的局部动态压力和气液界面上的拉普拉斯压力跃迁,模拟了蛞蝓气泡挤压和稳定环形流之间的过渡。平衡得出临界高度 Hc 与稳定气颈半径 rm 之比为 Hc/rm≈30.68Bo-0.904fD,re-0.210,其中邦德数 Bo=ΔρgD2/σ 和几何参数 fD,re=1-2reD2。
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来源期刊
Experimental Thermal and Fluid Science
Experimental Thermal and Fluid Science 工程技术-工程:机械
CiteScore
6.70
自引率
3.10%
发文量
159
审稿时长
34 days
期刊介绍: Experimental Thermal and Fluid Science provides a forum for research emphasizing experimental work that enhances fundamental understanding of heat transfer, thermodynamics, and fluid mechanics. In addition to the principal areas of research, the journal covers research results in related fields, including combined heat and mass transfer, flows with phase transition, micro- and nano-scale systems, multiphase flow, combustion, radiative transfer, porous media, cryogenics, turbulence, and novel experimental techniques.
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