The analysis of the binary homogeneous solution film behavior under thermal action

About the author:

Abstract:

Studying the processes occurring in liquid films under thermal influence allows improving a variety of technological systems, since a thin layer aids in providing a high intensity of heat and mass transfer and a significant surface of phase contact with a minimum liquid consumption. Many Russian and international works wrote about theoretical and experimental studies of film flows, though paid insufficient attention to the study of the behavior of films of a binary homogeneous solution. This article studies the behavior of a thin liquid film containing a volatile component during local heating of a solid horizontal substrate. The presented calculations were performed for an aqueous solution of isopropanol. The author describes the formation of a specific surface shape, which is formed with a sufficient increase in the substrate temperature and the initial film thickness — the so-called “liquid drop”, separated from the main volume of the liquid by a thin extended layer, which is explained by the sequential occurrence of thermal and concentration-capillary flows. The results show a significant influence of the Laplace pressure jump on the character of the entire process. In addition, the cooling of the substrate leads to multidirectional flows, but in the opposite directions. The analysis of the functions of the temperature of the film free surface, the volatile component concentration in the solution, and the vapor density over the free surface at different times is carried out. The velocity field in liquid and gas during the evolution of thermocapillary and concentration-capillary flows is illustrated.

References:

1. Andreev V. K., Gaponenko Yu. A., Goncharova O. N., Pukhnachev V. V. 2008. Modern Mathematical Models of Convection. Moscow: Fizmatlit. [In Russian]

2. Bekezhanova V. B., Goncharova O. N. 2018. “Problems of evaporative convection (review)”. Fluid Dynamics, vol. 53, no. 1, pp. S69-S102. DOI: 10.1134/S001546281804016X

3. Borodina K. A. 2020. “Dynamics of thermocapillary flow of a binary homogeneous solution film, taking into account the diffusion of a volatile component vapor”. Vestnik Bashkirskogo universiteta, vol. 25, no. 3, pp. 472-477. DOI: 10.33184/bulletin-bsu-2020.3.3 [In Russian]

4. Borodina K. A. 2020. “The model of the evolution of a binary homogeneous solution film under thermal action”. Tyumen State University Herald. Physical and Mathematical Modeling. Oil, Gas, Energy, vol. 6, no. 4 (24), pp. 48-68. DOI: 10.21684/2411-7978-2020-6-4-48-68 [In Russian]

5. Ivanova N. A., Borodina K. A. 2020. “Thin film thermocapillary motion of binary alcohol-containing solution”. Izvestiya of Saratov University. New Series. Series: Mathematics. Mechanics. Informatics, vol. 20, no. 1, pp. 64-78. DOI: 10.18500/1816-9791-2020-20-1-64-78 [In Russian]

6. Ivanova N. A., Bezuglyǐ B. A. 2009. “Influence of the liquid layer thickness on the growth of droplets controlled by the thermal action of laser radiation”. Technical Physics Letters, vol. 35, no. 4, pp. 293-295. DOI: 10.1134/S1063785009040014

7. Kabov O. A., Zaitsev D. V., Cheverda V. V., Bar-Cohen A. 2011. “Evaporation and flow dynamics of thin, shear-driven liquid films in microgap channels”. Experimental Thermal and Fluid Science, vol. 35, no. 5, pp. 825-831. DOI: 10.1016/j.expthermflusci.2010.08.001

8. Malyuk A. Yu., Ivanova N. A. 2017. “Optofluidic lens actuated by laser-induced solutocapillary forces”. Optics Communications, vol. 392, pp. 123-127. DOI: 10.1016/j.optcom.2017.01.040

9. Malyuk A. Yu., Ivanova N. A. 2018. “Varifocal liquid lens actuated by laser-induced thermal Marangoni forces”. Applied Physics Letters, vol. 112, no. 103701. DOI: 10.1063/1.5023222

10. Marchuk I. V. 2015. “Deformation of a Horizontal Liquid Layer under Flash Local Surface Heating”. Journal of Engineering Thermophysics, vol. 24, no. 4, pp. 381-385. DOI: 10.1134/S181023281504013X

11. Nepomnyashchy A., Simanovskii I., Legros J. C. 2012. Interfacial Convection in Multilayer System. Boston, MA: Springer. 513 pp. DOI: 10.1007/978-0-387-87714-3

12. Ovcharova A. S. 2011. “Features of the rupture of free hanging liquid film under the action of a thermal load”. Physics of Fluids, vol. 23, no. 10, art. 102106. DOI: 10.1063/1.3651361

13. Tatosova K. A., Malyuk A. Yu., Ivanova N. A. 2017. “Droplet formation caused by laser-induced surface-tension-driven flows in binary liquid mixtures”. Colloids and Surfaces A: Physicochem. Eng. Aspects, vol. 521, pp. 22-29. DOI: 10.1016/j.colsurfa.2016.07.004