Dynamics of droplet impingement on bioinspired surface: insights into spreading, anomalous stickiness and break-up

Roy, Durbar and Pandey, Khushboo and Banik, Meneka and Mukherjee, Rabibrata and Basu, Saptarshi (2019) Dynamics of droplet impingement on bioinspired surface: insights into spreading, anomalous stickiness and break-up. In: PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES, 475 (2229).

PDF Pro_Roy_Soc_Mat_Phy_Eng_Sci_475-2229.pdf - Published Version Restricted to Registered users only Download (2MB) | Request a copy

Abstract

Inspired by the self-cleaning ability of lotus leaves and stickiness (towards water) of rose petals, we investigate the droplet impact dynamics on such bioinspired substrates. Impact studies are carried out with water droplets for a range of impact velocities on glass, PDMS and soft lithographically fabricated replicas of the lotus leaf and rose petals, which exhibit near identical wetting properties as that of the original biological entities. In this work, we investigate the spreading, dewetting and droplet break-up mechanisms subsequent to impact. Surprisingly, the rose petal and lotus leaf replicas manifest similar impact dynamics. The observation is extremely intriguing and counterintuitive, as rose petal and its replicas are sticky in contrast to lotus leaves. However, these observations are based on experiments performed with sessile water droplets. By contrast, in the current study, we find that rose petal replicas exhibit non-sticky behaviour at the short time scale similar to(O(10(-3)))s similar to that exhibited by lotus leaf replicas. Air entrapment in the micrometre features of bioinspired surfaces prevent frictional dissipation of droplet kinetic energy, leading to contact edge recession. We have also unveiled interesting universal physics that govern the spreading, recession of the contact edge and subsequent break-up modes (ligament or bulb-ligament) of the droplet.

Item Type:	Journal Article
Publication:	PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
Publisher:	ROYAL SOC
Additional Information:	Copyright of this article belong to ROYAL SOC
Keywords:	interface; bioinspired surfaces; droplet; droplet break-up
Department/Centre:	Division of Interdisciplinary Sciences > Interdisciplinary Centre for Energy Research
Date Deposited:	04 Dec 2019 10:52
Last Modified:	04 Dec 2019 10:52
URI:	http://eprints.iisc.ac.in/id/eprint/63864

Actions (login required)

View Item