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arXiv · 2307.09812

Dynamics of an evaporating drop migrating in a Poiseuille flow

Anubhav Dubey·Kirti Chandra Sahu·Gautam Biswas
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Abstract

The evaporation of a liquid drop of initial diameter (Ddrop) migrating in a tube of diameter (D0) is investigated using the coupled level set and volume of fluid (CLSVOF) method focusing on determining the heat and mass transfer coefficients for a deforming drop. A robust phase change model is developed using an embedded boundary method under a finite difference framework to handle vaporizing flows. The model is extensively validated through simulations of benchmark problems such as arbitrary evaporation of a static drop and reproduction of psychrometric data. The results show that the Sherwood number (Sh) and the Nusselt number (Nu) reach a steady value after an initial transient period for the drop subjected to Hagen-Poiseuille flow. A parametric study is conducted to investigate the effect of drop deformation on the rate of evaporation. It is observed that Stefan flow due to evaporation has a negligible impact on the drop deformation dynamics. We also observed that, for different values of Ddrop/D0, the Sh follows a linear correlation with Re^{1/2}Sc^{1/3}.

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Anubhav Dubey, Kirti Chandra Sahu, Gautam Biswas. 2023-07-19. Dynamics of an evaporating drop migrating in a Poiseuille flow. https://arxiv.org/abs/2307.09812

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