Open Access

ARTICLE

Experimental Method for Studying the Effect of Dissolved Substances on the Evaporation Rate of Watwer Droplets Suspended in Air

Alexander A. Fedorets¹, Eduard E. Kolmakov¹, Anna V. Nasyrova¹, Dmitry N. Medvedev¹, Vyacheslav O. Mayorov², Vladimir Yu. Levashov², Leonid A. Dombrovsky^1,3,*

1 X-BIO Institute, University of Tyumen, 6 Volodarskogo St, Tyumen, 625003, Russia
2 Institute of Mechanics, Lomonosov Moscow State University, Moscow, 119991, Russia
3 Heat Transfer Department, Joint Institute for High Temperatures, 17A Krasnokazarmennaya St, Moscow, 111116, Russia

* Corresponding Author: Leonid A. Dombrovsky. Email:

Frontiers in Heat and Mass Transfer 2025, 23(4), 1091-1102. https://doi.org/10.32604/fhmt.2025.068244

Received 23 May 2025; Accepted 23 July 2025; Issue published 29 August 2025

Abstract

A new experimental method is developed to investigate the effect of dissolved substances on the evaporation rate of small water droplets suspended in the atmosphere. The laboratory setup is based on converting a generated droplet jet of complex structure into a directed flow of evaporating droplets falling in a vertical tube. Images of falling droplets captured by a high-speed camera through a window in the vertical channel wall are used to determine the sizes and velocities of individual droplets. The computational modeling of droplet motion and evaporation proved useful at all stages of the experimental work: from selecting the position of the vertical channel to processing the experimental data. It was found that even a 0.1% mass concentration of the dissolved ionic salt KCl has a considerable effect on decreasing the evaporation rate of the droplets. In contrast, a typical fungicide with a mass concentration of 2.5% has only a slight impact on the evaporation rate. The laboratory results enabled the authors to refine the evaporation model of water droplets to account for the presence of dissolved substances. Modified models of this type are expected to be useful in controling crop spraying and also in other potential applications.

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