Modelling of the thermocapillary convection in a sessile drop induced by a laser beam

About the authors:

Natalya A. Ivanova, Cand. Sci. (Phys.-Math.), Associate Professor, Department of Applied and Technical Physics, Institute of Physics and Technology, Head of Photonics and Microfluidics Research Laboratory, X-BIO Institute, University of Tyumen; eLibrary AuthorID, ORCID, Web of Science ResearcherID, Scopus AuthorID, n.ivanova@utmn.ru

Alexander Yu. Malyuk, Postgraduate Student, Department of Applied and Technical Physics, Junior Researcher of Photonics and Microfluidics Laboratory, University of Tyumen; ScopusID, a.malyuk@utmn.ru

Abstract:

The results of the numerical study of thermocapillary convection induced by the local heat flux in a sessile drop of non-volatile liquid with a fixed contact line are presented. The laser beam absorbed by the liquid is used as the source of heat flux. Sessile drops of benzyl alcohol and ethylene glycol with a volume of 0.6 mcl and heat flux power from 2 to 85 mW are observed in this paper. The model allows obtaining both velocity and temperature fields for both liquid and gas phases upon thermocapillary convection, evolution of free surface profile upon thermocapillary deformation. The relations between the focal length of refractive surface of the sessile drop and the heat flux are obtained. The comparison of the numerical and experimental data of the focal length shows a good correlation between numerical model and the experiment.

References:

1. Viznyuk S. A., Sukhodolskiy A. T. 1988. “Thermocapillary self-interaction of laser radiation in thin layers of an absorbing liquid”. Quantum Electronics, vol. 15, no 4, pp. 767-770. [In Russian]
2. Berge B., Peseux J. 2000. “Variable focal lens controlled by an external voltage: an application of electrowetting”. The European Physical Journal E, vol. 3, no 2, pp. 159-163. DOI: 10.1007/s101890070029
3. Cheng C.-C., Yeh J. A. 2007. “Dielectrically actuated liquid lens”. Optics Express, vol. 15, no 12, pp. 7140-7145. DOI: 10.1364/OE.15.007140
4. Dietzel M., Poulikakos D. 2005. “Laser-induced motion in nanoparticle suspension droplets on a surface”. Physics of Fluids, vol. 17, no 10, 102106. DOI: 10.1063/1.2098587
5. Dong L., Agarwal A. K., Beebe D. J., Jiang H. 2006. “Adaptive liquid microlenses activated by stimuli-responsive hydrogels”. Nature, vol. 442, no 7102, pp. 551-554. DOI: 10.1038/nature05024
6. Hitt D. L., Smith M. K. 1993. “Radiation-driven thermocapillary flows in optically thick liquid films”. Physics of Fluids A: Fluid Dynamics, vol. 5, no 11, pp. 2624-2632. DOI: 10.1063/1.858726
7. Jeong K.-H., Liu G. L., Chronis N., Lee L. P. 2004. “Tunable microdoublet lens array”. Optics Express, vol. 12, no 11, pp. 2494-2500. DOI: 10.1364/OPEX.12.002494
8. Karapetsas G., Chamakos N. T., Papathanasiou A. G. 2017. “Thermocapillary droplet actuation: effect of solid structure and wettability”. Langmuir, vol. 33, no 41, pp. 10838-10850. DOI: 10.1021/acs.langmuir.7b02762
9. Karpitschka S., Liebig F., Riegler H. 2017. “Marangoni contraction of evaporating sessile droplets of binary mixtures”. Langmuir, vol. 33, no 19, pp. 4682-4687. DOI: 10.1021/acs.langmuir.7b00740
10. Koyama D., Isago R., Nakamura K. 2011. “High-speed focus scanning by an acoustic variable-focus liquid lens”. Japanese Journal of Applied Physics, vol. 50, no 7, 07HE26. DOI: 10.1143/JJAP.50.07HE26
11. López C. A., Lee C.-C., Hirsa A. H. 2005. “Electrochemically activated adaptive liquid lens”. Applied Physics Letters, vol. 87, no 13, 134102, pp. 1-3. DOI: 10.1063/1.2058209
12. 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
13. Malyuk A. Yu., Ivanova N. A. 2018. “Varifocal liquid lens actuated by laser-induced thermal Marangoni forces”. Applied Physics Letters, vol. 112, no 10, 103701. DOI: 10.1063/1.5023222
14. Marchuk I. V. 2015. “Thermocapillary 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
15. Marchuk I. V. 2009. “Thermocapillary deformation of a thin locally heated horizontal liquid layer”. Journal of Engineering Thermophysics, vol. 18, no 3, pp. 227-237. DOI: 10.1134/S1810232809030047
16. Moran P. M., Dharmatilleke S., Khaw A. H., Tan K. W., Chan M. L., Rodriguez I. 2006. “Fluidic lenses with variable focal length”. Applied Physics Letters, vol. 88, no 4, 041120, pp. 1-3. DOI: 10.1063/1.2168245
17. Seow Y. C., Liu A. Q., Chin L. K., Li X. C., Huang H. J., Cheng T. H., Zhou X. Q. 2008. “Different curvatures of tunable liquid microlens via the control of laminar flow rate”. Applied Physics Letters, vol. 93, no 8, 084101. DOI: 10.1063/1.2976210
18. Tsoumpas Y., Dehaeck S., Rednikov A., Colinet P. 2015. “Effect of Marangoni flows on the shape of thin sessile droplets evaporating into air”. Langmuir, vol. 31, no 49, pp. 13334-13340. DOI: 10.1021/acs.langmuir.5b02673
19. Uchiyama K., Hibara A., Kimura H., Sawada T., Kitamori T. 2000. “Thermal lens microscope”. Japanese Journal of Applied Physics, vol. 39, no 9A, pp. 5316-5322. DOI: 10.1143/JJAP.39.5316