Post-doctoral candidate on Bio-inspired hybrid laser smart texturing of SLIPS for anti-icing properties

Research field presentation:

Secondary refrigeration is an effective way to drastically reduce the quantity of primary refrigerant fluid used while improving energy efficiency by storing and transporting energy dense secondary fluids. These ice slurries, made of ice crystals suspended in aqueous solution, are unfortunately not yet widespread due to an over-investment related to scraped surface or supercooling type generators. Within this COOLISSE project, our objective is thus to participate in the energy optimization of the refrigeration sector by designing a new type of ice slurry generator. Our aim is therefore to develop stainless steel surfaces on which the ice formed could be carried away by the flow of the fluid, without rotating scraper blades. These original non-wetting micro/nanostructured surfaces, inspired from nature, displaying anti-icing properties will be obtained by an original and efficient combination of processes selected from the following: additive manufacturing (to yield micro-structures), subtractive processes based on electrochemical etching and photolithography and finally femtosecond laser ablation (to reach nanometer scale roughness) that will allow obtaining a multiscale and very dense textured stainless steel surface. These surfaces will be then infused by inert liquid in order to obtain slippery infused surfaces (SLIPS). The second objective of the project is to develop advanced and breakthrough knowledge on the surface characterization under flow at low temperature [-15°C to 0°C]. The potential in anti-icing applications of the designed surfaces will be proven by investigating their action mechanisms on ice formation, analyzing the freezing time, adhesion strength and nucleation in the freezing process. In parallel a comprehensive numerical method will be developed to describe the thermal equilibrium state, heat flux and gas-solid-liquid interface changes during freezing and phase change. An empirical correlation of the data obtained will also be investigated allowing access to additional feedback to optimize the design of our surfaces. Environmental impact and potential gain of these surfaces on slurry fabrication process will also be compared to usual processes using multiple criteria analyses like Life Cycle Assessment (LCA).

Description of the activities to be done by the postdoc in LTDS:

• Bibliographic review on bio-inspired SLIPS surfaces
• Femtosecond laser multiscale surface texturing of bioinspired SLIPS surfaces
• 3D additive manufacturing of complex surfaces
• Hybridation of both processes of surface texturing
• Wetting and adhesion characterization of textured and SLIPS surfaces

Main research field:

• Materials
• Surface Texturing
• Laser processes
• Femtosecond laser
• Additive manufacturing
• Wetting
• Adhesion
• Slippery Liquid-Infused Porous Surfaces
• Tribology
• Physics
• Biomimicry