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How merging droplets jump off a superhydrophobic surface: Measurements and model

Timothée Mouterde1,2,*, Thanh-Vinh Nguyen3,†, Hidetoshi Takahashi4,‡, Christophe Clanet1,2,§, Isao Shimoyama3,4, and David Quéré1,2

  • 1Physique et Mécanique des Milieux Hétérogènes, UMR 7636 du CNRS, ESPCI, 75005 Paris, France
  • 2Laboratoire d'Hydrodynamique de l'X, UMR 7646 du CNRS, École Polytechnique, 91128 Palaiseau, France
  • 3Information and Robot Technology Research Initiative, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, Japan
  • 4Department of Mechano-Informatics, Graduate School of Information Science and Technology, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, Japan

  • *timothee.mouterde@polytechnique.org
  • †vinh@leopard.t.u-tokyo.ac.jp
  • ‡takahashi@leopard.t.u-tokyo.ac.jp
  • §clanet@ladhyx.polytechnique.fr
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Phys. Rev. Fluids 2, 112001(R) – Published 16 November, 2017

DOI: https://doi.org/10.1103/PhysRevFluids.2.112001

Abstract

We investigate how drops merging on a nonwettable surface jump off this surface, for both symmetric and asymmetric coalescences. For this purpose, we design and build a microelectromechanical system sensor able to quantify forces down to the micro-Newton scale at a high acquisition rate (200 kHz). Using this device, we perform direct force measurements of self-propelled droplets coupled to high-speed imaging. Experimental data show that the total momentum of the drop after coalescence mainly depends on the size of the smaller drop. Exploiting this finding, we quantitatively predict the takeoff speed of jumping drop pairs and show how to correct the usual argument based on energy conservation.

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References (24)

  1. R. Blossey, Self-cleaning surfaces—virtual realities, Nat. Mater. 2, 301 (2003).
  2. Y.-T. Cheng and D. E. Rodak, Is the lotus leaf superhydrophobic? Appl. Phys. Lett. 86, 144101 (2005).
  3. Y.-T. Cheng, D. E. Rodak, A. Angelopoulos, and T. Gacek, Microscopic observations of condensation of water on lotus leaves, Appl. Phys. Lett. 87, 194112 (2005).
  4. K. A. Wier and T. J. McCarthy, Condensation on ultrahydrophobic surfaces and its effect on droplet mobility: Ultrahydrophobic surfaces are not always water repellant, Langmuir 22, 2433 (2006).
  5. C.-H. Chen, Q. Cai, C. Tsai, C.-L. Chen, G. Xiong, Y. Yu, and Z. Ren, Dropwise condensation on superhydrophobic surfaces with two-tier roughness, Appl. Phys. Lett. 90, 173108 (2007).
  6. C. Dorrer and J. Ruehe, Wetting of silicon nanograss: From superhydrophilic to superhydrophobic surfaces, Adv. Mater. 20, 159 (2008).
  7. J. B. Boreyko and C.-H. Chen, Self-Propelled Dropwise Condensate on Superhydrophobic Surfaces, Phys. Rev. Lett. 103, 184501 (2009).
  8. K. Rykaczewski, W. A. Osborn, J. Chinn, M. L. Walker, J. H. J. Scott, W. Jones, C. Hao, S. Yao, and Z. Wang, How nanorough is rough enough to make a surface superhydrophobic during water condensation? Soft Matter 8, 8786 (2012).
  9. R. Enright, N. Miljkovic, A. Al-Obeidi, C. V. Thompson, and E. N. Wang, Condensation on superhydrophobic surfaces: The role of local energy barriers and structure length scale, Langmuir 28, 14424 (2012).
  10. J. Liu, H. Guo, B. Zhang, S. Qiao, M. Shao, X. Zhang, X.-Q. Feng, Q. Li, Y. Song, L. Jiang, and J. Wang, Guided self-propelled leaping of droplets on a micro-anisotropic superhydrophobic surface, Angew. Chem., Int. Ed. 55, 4265 (2016).
  11. H. Cha, C. Xu, J. Sotelo, J. M. Chun, Y. Yokoyama, R. Enright, and N. Miljkovic, Coalescence-induced nanodroplet jumping, Phys. Rev. Fluids 1, 064102 (2016).
  12. T. Mouterde, G. Lehoucq, S. Xavier, A. Checco, C. T. Black, A. Rahman, T. Midavaine, C. Clanet, and D. Quéré, Antifogging abilities of model nanotextures, Nat. Mater. 16, 658 (2017).
  13. F. Liu, G. Ghigliotti, J. J. Feng, and C.-H. Chen, Self-propelled jumping upon drop coalescence on Leidenfrost surfaces, J. Fluid Mech. 752, 22 (2014).
  14. F. Liu, G. Ghigliotti, J. J. Feng, and C.-H. Chen, Numerical simulations of self-propelled jumping upon drop coalescence on non-wetting surfaces, J. Fluid Mech. 752, 39 (2014).
  15. C. Lv, P. Hao, Z. Yao, Y. Song, X. Zhang, and F. He, Condensation and jumping relay of droplets on lotus leaf, Appl. Phys. Lett. 103, 021601 (2013).
  16. F.-C. Wang, F. Yang, and Y.-P. Zhao, Size effect on the coalescence-induced self-propelled droplet, Appl. Phys. Lett. 98, 053112 (2011).
  17. R. Enright, N. Miljkovic, J. Sprittles, K. Nolan, R. Mitchell, and E. N. Wang, How coalescing droplets jump, ACS Nano 8, 10352 (2014).
  18. T.-V. Nguyen, B.-K. Nguyen, H. Takahashi, K. Matsumoto, and I. Shimoyama, High-sensitivity triaxial tactile sensor with elastic microstructures pressing on piezoresistive cantilevers, Sens. Actuators, A 215, 167 (2014).
  19. M. Gel and I. Shimoyama, Force sensing submicrometer thick cantilevers with ultra-thin piezoresistors by rapid thermal diffusion, J. Micromech. Microeng. 14, 423 (2004).
  20. M.-K. Kim, H. Cha, P. Birbarah, S. Chavan, C. Zhong, Y. Xu, and N. Miljkovic, Enhanced jumping-droplet departure, Langmuir 31, 13452 (2015).
  21. A. H. R. Buller, Researches on Fungi, Vol. 1 (Longmans, Green, and Co., London, 1909).
  22. J. Turner and J. Webster, Mass and momentum transfer on the small scale: How do mushrooms shed their spores? Chem. Eng. Sci. 46, 1145 (1991).
  23. A. Pringle, S. N. Patek, M. Fischer, J. Stolze, and N. P. Money, The captured launch of a ballistospore, Mycologia 97, 866 (2005).
  24. X. Noblin, S. Yang, and J. Dumais, Surface tension propulsion of fungal spores, J. Exp. Biol. 212, 2835 (2009).

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Phys. Rev. Fluids 2, 112001(R)– Published 16 November, 2017
  • Received 6 June 2017

©2017 American Physical Society

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