Heat transfer characteristics and entropy generation of electroosmotic flow in a rotating rectangular microchannel

This study aims to investigate thermal transport characteristics and analyze entropy generation of thermally fully-developed electroosmotic flow (EOF) in a rotating rectangular microchannel subject to constant wall heat flux. In the two-dimensional rectangular domain, the solutions for electric potential and flow velocity are obtained in terms of eigenfunction series by means of separation of variables technique, and the temperature field, which takes into consideration the effects of heat convection, Joule heating and viscous dissipation, is numerically solved. Results are generated to show the influences due to various factors, including rotational frequency, depth/width ratio of the rectangular channel, distribution of zeta potentials, strength of Joule heating and magnitude of wall heat flux, on the thermal transport characteristics. In particular, how the Nusselt number and the entropy generation vary with these factors are explored in details. To pursue optimization in energy utilization, an optimal aspect ratio is found at which the minimum entropy generation can be achieved. We believe that the findings in the present study will be useful in the design of energy efficient micro-systems which utilize the dual electrokinetic and centrifugal pumping effects.