Irreversibility analysis in a slip aided electroosmotic flow through an asymmetrically heated microchannel: The effects of joule heating and the conjugate heat transfer

Abstract

In this article, we discuss about the entropy generation minimization in a slip-modulated electrically actuated transport through an asymmetrically heated microchannel. While investigating the underlying thermo-hydrodynamics towards minimizing the irreversibility of the system under present consideration, we take the combined effects of Joule heating and the conjugate transfer of heat into account in this analysis. We primarily focus to tune the relevant thermo-physical as well as geometrical parameters towards minimizing the global irreversibility of the system. We show that the cooperative-correlative effects of the temperature gradient (between walls and fluid) and viscous dissipation in the system, as modulated by the slipping hydrodynamics stemming from the interfacial electrochemistry and Joule heating effects originating from higher conduction currents, bring in a change in the underlying thermal transport characteristics of heat, leading to an alteration in thermodynamic irreversibility in the system. We unveil optimum values of geometrical and thermo-physical parameters for which a change in thermal transport of heat as triggered by the viscous dissipation and joule heating effect leads to a minimum entropy generation in the system. Moreover, we show that the ionic concentration of the electrolyte present in the fluid can fetch a reduction in the irreversibility as well. We believe that the insights gained from this analysis may be useful for constructing the well-optimized futuristic micro heat exchanging systems/devices, typically used in MEMS.