Significant and stable drag reduction with air rings confined by alternated superhydrophobic and hydrophilic strips.

ABSTRACT: Superhydrophobic surfaces have the potential to reduce the viscous drag of liquids by significantly decreasing friction at a solid-liquid interface due to the formation of air layers between solid walls and interacting liquids. However, the trapped air usually becomes unstable due to the finite nature of the domain over which it forms. We demonstrate for the first time that a large surface energy barrier can be formed to strongly pin the three-phase contact line of air/water/solid by covering the inner rotor of a Taylor-Couette flow apparatus with alternating superhydrophobic and hydrophilic circumferential strips. This prevents the disruption of the air layer, which forms stable and continuous air rings. The drag reduction measured at the inner rotor could be as much as 77.2%. Moreover, t

SUBMITTER: Hu H 

PROVIDER: S-EPMC5580886 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature