THERMAL SCIENCE

International Scientific Journal

Dorra Khilifi

,

Walid Foudhil

,

Kamel Fahem

,

Souad Harmand

,

Sadok Ben Jabrallah

STUDY OF TRANSIENT CONDENSATION OCCURRING DURING THE STARTING OF THE EVAPORATION OF A DROPLET DEPOSITED ON A HEATED SUBSTRATE

ABSTRACT
The evaporation of a drop deposited on a heated substrate is a complex process, which combines several phenomena such as the Marangoni effect, mass and thermal transfers, etc. We developed, in this paper, a mathematical model and a numerical simulation code used to carry out an in-depth study about the evaporation of a drop deposited on a heated substrate surrounded by air. This numerical study was supported by experimental work. The numerical findings obtained showed the existence of a condensation phenomenon for certain configurations. At the beginning of the experiment, the evaporation started at the triple point. However, a local region of the interface remained relatively cold. In this region, the concentration gradient (Cv, Csat) directed from the liquid-gas interface to the air resulted in condensation of water steam. Although this phenomenon is temporary and visible only at the start of evaporation process, its study makes it possible to better understand and optimize the evaporation kinetics.
KEYWORDS
Sessile droplet, evaporation, Steam diffusion, Condensation.
PAPER SUBMITTED: 2018-11-22
PAPER REVISED: 2019-08-29
PAPER ACCEPTED: 2019-09-06
PUBLISHED ONLINE: 2019-10-06
DOI REFERENCE: https://doi.org/10.2298/TSCI181122377K
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2020, VOLUME 24, ISSUE Issue 6, PAGES [4075 - 4087]
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Study of transient condensation occurring during the starting of the evaporation of a droplet deposited on a heated substrate

© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence