Numerical Analysis of Active Induced Velocity in Microchannel with Different Electrode Bed Configuration: Electrothermal Pumping

This study investigates the influence of geometric alterations and applied voltage on electrothermal pumping within a rectangular microchannel featuring two electrodes. Using OpenFOAM with conjugate heat transfer, numerical simulations can show how the electric, flow, and thermal fields are linked. The study concentrates on square indentations and protrusions of different heights (5, 10, and 15 µm) and their effects on fluid velocity, pressure, and temperature. The depth of an indentation has a big effect on flow. Deeper indentations slow down the flow and make it harder for the flow to go back into the indentation. Different heights of protrusions affect flow patterns in different ways: moderate heights spread out the velocity, while taller protrusions keep flow to the upper channel region. It's interesting to note that the height of the protrusion doesn't have much of an effect on the average outlet velocity, but the depth of the indentation does. The results also back up the idea that the fourth power of the applied voltage is related to the generated velocity. Elliptical electrodes are best for bio-relevant applications that need stable throughput and gentle thermal conditions. When low-voltage actuation is important, triangular electrodes can be used, but to avoid thermal hotspots, precautions like heat-spreading layers or duty-cycled excitation are needed.