106 Thermal Analysis of Electrokinetic Flows in Planar Microchannel

Abstract

Significance of Joule heating on combined electroosmotic and pressure driven flows inside a straight microchannel is estimated for isoflux channel wall condition. Temperature distribution is obtained in both thermally developing and fully developed region from analytic solution of steady state energy equation. The length of entrance regions is determined from the non-dimensional heat transfer characteristics. Our analytical solution matches with existing literature for slug, pressure driven, and pure electroosmotic flow cases. The thermal developing speed and heat transfer characteristics change with applied pressure gradient along the microchannel. The Nusselt number does not depend on the magnitude of Joule heating if and only if there is no pressure gradient in the flow.