Sustained drag reduction in a turbulent flow using a low-temperature Leidenfrost surface.

ABSTRACT: Skin friction drag contributes a major portion of the total drag for small and large water vehicles at high Reynolds number (Re). One emerging approach to reducing drag is to use superhydrophobic surfaces to promote slip boundary conditions. However, the air layer or "plastron" trapped on submerged superhydrophobic surfaces often diminishes quickly under hydrostatic pressure and/or turbulent pressure fluctuations. We use active heating on a superhydrophobic surface to establish a stable vapor layer or "Leidenfrost" state at a relatively low superheat temperature. The continuous film of water vapor lubricates the interface, and the resulting slip boundary condition leads to skin friction drag reduction on the inner rotor of a custom Taylor-Couette apparatus. We find that skin frictio

SUBMITTER: Saranadhi D 

PROVIDER: S-EPMC5065253 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature