Prediction of resistance induced by surface complexity in lubricating layers: Application to superhydrophobic surfaces

Inspired by the ability of lotus leaves to repel water, super hydrophobic coatings are engineered and used reduce drag. The prospect drag reduction depends on surface geometry flow conditions. In this work, we suggest a new mechanism incorporating resistance induced inside lubricating layer which could be responsible for decrease drag-reduction performance in laminar regime. A simple model combining Stokes' theory around sphere numerically correlated slip velocity, takes into account tortuosity porosity texture, is presented validated against laboratory experiments.