Optimizing fiber cross-sectional shape for improving stability of air–water interface over superhydrophobic fibrous coatings

In this letter, a mathematical force-balance formulation is developed that can be used to predict the critical pressure, the hydrostatic pressure above which the surface starts to depart from the non-wetting state, for superhydrophobic surfaces comprised of highly aligned fibers (e.g., biased AC-electrospun coatings) with arbitrary cross-sectional shapes. We have also developed a methodology for optimizing the fiber cross-sections to maximize the critical pressure of the surface, using the Euler–Lagrange equation. A case study is presented to better demonstrate the application of our method. VC 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4711800]