This paper describes a numerical analysis with the use of a finite-volume scheme on the liquid flow and heat transfer in microchannels, with streaming potential as the driving force. The concept of electric double layer (EDL) was introduced to explain the microscale deviation. Governing equations were derived for fully developed rectangular microchannel flows. Towards a realistic modeling of the rectangular microchannels, a conjugate analysis, that solves both the solid and liquid regions, was performed. An additional source term resulting from the EDL effects was introduced in the conventional momentum equation, thereby modifying the flow and heat transfer characteristics. In this work, analyses concerning the effects of ionic concentration and zeta potential and channel dimensions were discussed.

The predicted results showed significant deviations in the velocity and temperature profiles under EDL effects. Friction factors and Nusselt numbers were calculated and compared for both EDL and non-EDL considerations. Stronger deviations were also observed as the aspect ratio decreases, suggesting the importance of EDL in microscale liquid flow. KW - EDL effects KW - pressure-driven flows KW - microchannel KW - simulation KW - FVM DO - 10.3970/cmes.2002.003.351