Frost-free zone on macrotextured surfaces.

Area of Science:

• Materials Science
• Surface Science
• Physics

Background:

• Developing effective anti-icing surfaces is challenging due to degradation issues like mechanical wear.
• Existing anti-icing strategies often rely on micro/nanoscale textures, with limited success in preventing frost formation.
• Natural frost patterns on leaves offer inspiration for novel surface designs.

Purpose of the Study:

• To investigate frost formation on millimeter-scale serrated surfaces.
• To understand the mechanisms behind spatially controlled frost inhibition.
• To provide a framework for designing advanced anti-icing surfaces.

Main Methods:

• Experimental observation of condensation frosting on serrated surfaces.
• Numerical simulations based on steady-state diffusion.
• Analytical modeling considering boundary conditions.

Main Results:

• Frost initiates on the peaks of serrated surfaces, regardless of surface chemistry.
• Valleys remain frost-free due to droplet evaporation, creating a frost-free zone.
• The frost-free area fraction depends on geometric parameters and ambient conditions.

Conclusions:

• Millimeter-scale serrated structures enable spatial control over frost formation.
• This approach offers a robust anti-icing mechanism, distinct from traditional methods.
• The findings provide a unified framework for designing surfaces for controlled frost, crystal growth, and material deposition.