Thermal transport in laminar flow over superhydrophobic surfaces, utilizing an effective medium approach

Abstract

An analytical methodology to characterizing the effects of heat transport in internal laminar flows over ridged patterns, mimicking superhydrophobic surfaces, is indicated. The finite slip velocity on such surfaces and the thermal conductivity characteristics of the constituent material are both shown to modify the convective heat transport in the fluid. We use an effective medium approach to model the lowered thermal conductivity caused by the presence of air in the ridge interstices. The proposed analytical solutions for fully developed flow were verified through comparison with numerical simulations for a periodically ridged geometry in laminar flow. While the convective heat transport and the Nusselt Number (Nu) increase due to the modified fluid velocity profile on superhydrophobic surfaces, the decrease in the thermal conductivity of the substrate may play a larger role in determining the overall heat transfer in the channel.