Modelling of pressure-driven liquid flows in conjugate rectangular microchannel with electric double layer effects

This work deals with a code development using a finite-volume scheme for th e liquid flow and heat transfer in microchannels, with streaming potential as the driving force. The concept of electric double layer (EDL) was introd uced to explain the microscale deviation. Governing equations were derived for fully developed rectangular microchannels pressure-driven flows. Toward s a realistic modeling of the problems, a conjugate analysis, that solves b oth the solid and liquid regions, was conducted. An additional source term resulting from the EDL effects was introduced in the conventional momentum equation, thereby modifying the flow and heat transfer characteristics. Ana lysis concerning the effects of ionic concentration and zeta potential and channel dimensions were included. The computed results reveal significant deviations in the velocity and temp erature profiles under EDL effects. Predicted friction factors and Nusselt numbers were compared for both EDL and non-EDL considerations. Stronger dev iations were observed as the aspect ratio decreases, indicating the role of EDL effects in microscale liquid flow.