Motion Characteristics of Vibrated Droplets on Micropillared Surface with Gradient Energy

doi:10.16183/j.cnki.jsjtu.2020.079

Abstract

Abstract:

A gradient energy surface with micropillared structures is prepared by photolithography using polydimethylsiloxane (PDMS) as the substrate. The dynamic characteristics of vibrated droplets on the gradient energy surface with micropillared structures are studied by a high-speed camera. The influence of geometric parameters of the gradient energy surface with micropillared structures on the motion characteristics of vibrated droplets is analyzed. It is found that the droplets begin to wriggle when a certain vibration frequency is exerted on the gradient energy surface with micropillared structures and the vibration amplitude reaches a certain threshold. With the increase of the amplitude, the droplets move from the larger area fraction to the smaller area fraction. At the same vibration frequency, the acceleration of droplets gradually decreases as the amplitude increases. At the same time, compared to the region with a smaller area fraction, the acceleration of droplets motion is smaller in the region with a larger area fraction. In the region with a large area fraction, the range of wet contact diameter has a greater variation than the region with a small area fraction. A model is established using the mechanics and surface physical chemistry theory, and the influence of the surface microstructure on droplet motion characteristics is analyzed.

Key words: droplets, dynamics, surface, vibration, acceleration, gradient energy

CLC Number:

TK121

XIONG Xuejiao, JIA Zhihai, DENG Yong, FEI Yuanyuan. Motion Characteristics of Vibrated Droplets on Micropillared Surface with Gradient Energy[J]. Journal of Shanghai Jiao Tong University, 2021, 55(4): 455-461.

Figures/Tables 7

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