Prompting Splash Impact on Superamphiphobic Surfaces by Imposing a Viscous Part

Fanfei Yu; Shiji Lin; Jinlong Yang; Yue Fan; Dehui Wang; Longquan Chen; Xu Deng

doi:10.1002/advs.201902687

Prompting Splash Impact on Superamphiphobic Surfaces by Imposing a Viscous Part

Adv Sci (Weinh). 2020 Jan 10;7(4):1902687. doi: 10.1002/advs.201902687. eCollection 2020 Feb.

Authors

Fanfei Yu¹, Shiji Lin², Jinlong Yang¹, Yue Fan¹, Dehui Wang¹, Longquan Chen², Xu Deng¹

Affiliations

¹ Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China Chengdu 610054 P. R. China.
² School of Physics University of Electronic Science and Technology of China Chengdu 610054 P. R. China.

Abstract

It is widely acknowledged that splash impact can be suppressed by increasing the viscosity of the impinging drop. In this work, however, by imposing a highly viscous drop to a low-viscosity drop, it is demonstrated that the splash of the low-viscosity part of this Janus drop on superamphiphobic surfaces can be significantly promoted. The underlying mechanism is that the viscous stress exerted by the low-viscosity component drives the viscous component moving in the opposite direction, enhancing the spreading of the low-viscosity side and thereby its rim instability. The threshold velocity, above which splashing occurs, can be tuned by varying the viscosity ratio of the Janus drop. Moreover, the impact of the Janus drop can be employed to verify the mechanism of splash.

Keywords: drop impact; splash; superamphiphobic surfaces; viscous ratios.