Open AccessStick-slip transition of a water droplet vibrated on a superhydrophobic surface
Author(s) -
Zhou Jian-Chen,
Geng Xing-Guo,
Lin Ke-Jun,
Yongjian Zhang,
Zang Du-Yang
Publication year - 2014
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.63.216801
Subject(s) - oscillation (cell signaling) , vibration , materials science , slip (aerodynamics) , mechanics , low frequency , phase (matter) , rayleigh scattering , optics , physics , acoustics , chemistry , thermodynamics , biochemistry , quantum mechanics , astronomy
We have studied the vibration behavior of a water droplet vibrated on a superhydrophobic surface via a high-speed camera. The resonance frequencies of the droplet satisfy the Rayleigh equation, suggesting that the droplet on a superhydrophobic surface can be regarded as a free droplet. Its real oscillation frequency is half of the driving frequency when it is vibrated at low frequencies(<200 Hz). It shows large shape deformation from a compressed puddle to a stretched spheroid. The three-phase contact line exhibits a stick-slip behavior. However, when the droplet is vibrated at frequencies greater than 200 Hz, the three-phase contact line is pinned to the substrate and the droplet is vibrated at the same frequencies as the external driving frequencies. It is found that the oscillation of the contact line and the large shape deformation of the droplet are responsible for the distinct behavior at low frequency.