Design of ice-phobic surfaces for aerospace applications: work with Honeywell Bangalore
Slippery, liquid-infused porous surfaces (SLIPS) with nanostructured coating have been proposed about a decade ago  as a promising potential candidate to minimize contact angle hysteresis and consequent pinning of the three-phase contact line on droplets forming on a solid surface. The pinning of the contact line prevents the sliding of water-droplets nucleating on these surfaces thus allowing sufficient time for freezing and ice-formation. This can be extremely undesirable when occurring inside aircraft engines and require efficient removal. In recent years, strategies to counter ice formation have shifted from removal of ice to designing surfaces which inhibit their formation in the first place. Among various proposed techniques for designing ice-phobic surfaces, liquid infused porous surfaces appear to be the most promising. SLIPS can significantly minimize contact angle hysteresis  e.g. for liquid infused aluminium surfaces this hysteresis can be ~ 2 degrees in comparison to the same surface without the infusement where it is much higher ~ 40 degrees . Consequently, on inclined surfaces the maximum size of pinned droplets goes down from 6 mm (uninfused surfaces) to ~600 microns (SLIPS) . Additionally, ice when formed should
have low adhesion strength on such surfaces allowing for efficient removal. An important set of criteria for aerospace applications is to ensure that the liquid infused surface should continue to be stable under imposed shear, either gravity induced or via flow of an external fluid . In addition, the liquid layer needs to be remain stable to successive icing and de-icing cycles suffering little depletion  and potentially having self-healing properties. The original SLIPS lubricating film was found to have significant depletion via drainage when the substrate was stored vertically  and rectifications to this have been subsequently proposed .
The aim of this M.Tech. project is to explore, optimize and develop an ice-phobic surface using various techniques suggested in the literature including SLIPS but also other techniques [5,6,7] for developing an anti-icing coating for Aerospace applications. The student will have the opportunity to work in close collaboration with Honeywell at Bangalore including the possibility of visiting and conducting experiments at their Research & Development Centre at Bangalore. In addition, the student may also be paid a suitable honorarium at the end of satisfactory competition of the project. The student is expected to design a setup for controlled icing and de-icing cycles at IIT Bombay in collaboration with Honeywell Bangalore. The guides at IIT Bombay will be Prof. Ratul Dasgupta & Prof. Guruswamy Kumaraswamy and Mr. Dilip Vasisht at Honeywell Bangalore.
1. Liquid-Infused Nanostructured Surfaces with Extreme Anti-Ice and Anti-Frost Performance, Philseok Kim, Tak-Sing Wong, Jack Alvarenga, Michael J. Kreder, Wilmer E. Adorno-Martinez and Joanna Aizenberg, 2012, ACS Nano
2. Bio-Inspired Strategies for Anti-Icing, Jianyong Lv et al, ACS Nano, 2014.
3. Transparency and damage tolerance of patternable omniphobic lubricated surfaces based on inverse colloidal monolayers, Vogel etl al, Nature 2013
4. Ice Adhesion on Lubricant-Impregnated Textured Surfaces, Subramanyam et al, Langmuir 2013
5. Magnetic slippery extreme icephobic surfaces, Irajizad et al, Nature comm. 2016
6. Recent development in the fabrication of self-healing superhydrophobic surfaces, E. K. Sam et al, Chemical Engg. Journal, 2019
7. Uniting Superhydrophobic, Superoleophobic and Lubricant Infused Slippery Behavior on Copper Oxide Nano-structured Substrates, S. K. Ujjain, Sci. Reports, 2016.
8. Shear-Driven Failure of Liquid-Infused Surfaces, Wexler et al, Phys. Rev. Lett, 2015.