Journal of ILASS-Korea (한국분무공학회지)

Institute for Liquid Atomization and Spray Systems-Korea (한국분무공학회)
권호 표지
DOI QR코드

DOI QR Code

Spreading and Deposition Characteristics of a Water Droplet Impacting on Hydrophobic Textured Surfaces

소수성 텍스쳐 표면에 충돌한 단일 액적의 퍼짐 및 고착 특성

  • Received : 2012.02.02
  • Accepted : 2012.03.12
  • Published : 2012.03.30
Download PDF
⟨ Previous Next ⟩

Abstract

The present study conducts experimental investigation on spreading and deposition characteristics of a $4.3{\mu}l$ de-ionized (DI) water droplet impacting upon aluminum (Al 6061) flat and textured surfaces. The micro-textured surface consisted the micro-hole arrays (hole diameter: $125{\mu}m$, hole depth: $125{\mu}m$) fabricated by the conventional micro-computer numerical control (${\mu}$-CNC) milling machine process. We examined the surface effect of texture area fraction ${\varphi}_s$ ranging from 0 to 0.57 and impact velocity of droplet ranging from 0.40 m/s to 1.45 m/s on spreading and deposition characteristics from captured images. We used a high-speed camera to capture sequential images for investigate spreading characteristics and the image sensor to capture image of final equilibrium deposition droplet for analyze spreading diameter and contact angle. We found that the deposition droplet on textured surfaces have different wetting states. When the impact velocity is low, the non-wetting state partially exists, whereas over 0.64 m/s of impact velocity, totally wetting state is more prominent due to the increase kinetic energy of impinging droplet.

Keywords

References

  1. A. L. Yarin, "Drop impact dynamics: splashing, spreading, receding, bouncing", Annu. Rev. Fluid Mech., Vol. 38, 2005, pp. 159-192.
  2. C. G. L. Furmidge, "Studies at phase interfaces. I. The sliding of liquid drops on solid surfaces and a theory for spray retention", J. Colloid. Sci., Vol. 17, 1962, pp. 309-324. https://doi.org/10.1016/0095-8522(62)90011-9
  3. H. Liu, "Science and engineering of droplets - fundamentals and applications", William Andrew publishing, 2000.
  4. R. Rioboo, C. Tropea and M. Marengo., "Outcomes from a drop impact on solid surfaces", Atomization Sprays, Vol. 11, 2001, pp. 155-165.
  5. S. Chandra and C. T. Avedisian, "On the collision of a droplet with a solid surfaces", Proc. R. Soc. Lond. A., Vol. 432, 1991, pp. 13-41.
  6. R. Rioboo, M. Voue, A. Vaillant, and J. De Coninck, "Drop Impact on Porous Superhydrophobic Polymer Surfaces", Langmuir, Vol. 24, 2008, pp. 14074-14077. https://doi.org/10.1021/la802897g
  7. M. Pasandideh-Fard, R. Bhola, S. Chandra and J. Mostaghimi, "Deposition of Tin Droplets on a Steel Plate: Simulation and Experiments", Int. J. Heat Mass Transfer, Vol. 41, 1998, pp. 2929-2945. https://doi.org/10.1016/S0017-9310(98)00023-4
  8. H. S. Park, J. Y. Zhu, and J. F. Morris, "Single Drop Impaction on a Solid Surface", AIChE J., Vol. 49, 2003, pp. 2461-2471. https://doi.org/10.1002/aic.690491003
  9. Z. Wang, C. Lopez, A. Hirsa and N. Koratkar, "Impact Dynamics and Rebound of Water Droplets on Superhydrophobic Carbon Nanotube Arrays", Appl. Phys. Lett., Vol. 91, 2007, pp. 023105. https://doi.org/10.1063/1.2756296
  10. L. Xu, "Liquid Drop Splashing on Smooth, Rough, and Textured Surfaces", Phys. Rev. E: Stat. Phys. Plasmas Fluids Relat. Interdisciplin. Top., Vol. 75, 2007, pp.056316.
  11. Y. C. Jung, and B. Bhushan, "Dynamic Effects of Bouncing Water Droplets on Superhydrophobic Surfaces", Langmuir, Vol. 24, 2008, pp. 6262-6269. https://doi.org/10.1021/la8003504
  12. J. B. Lee and S.H. Lee, "Dynamic wetting and spreading characteristics of a liquid droplet impinging on hydrophobic textured surfaces", Langmuir, Vol. 27, 2011, pp. 6565-6573. https://doi.org/10.1021/la104829x
  13. A.B.D. Cassie and S. Baxter, "Wettability of porous surfaces", Trans. Faraday Soc., Vol. 40, 1994, pp. 546-551.
  14. R. E. Ford and C. G. L. Furmidge, "Impact and spreading of spray drops on foliar surfaces", Society of Chemical Industry: Monograph, No.25, 1967, pp. 417-431.