The effect of electrode height on the performance of travelling-wave electroosmotic micropumps

Arrays of microelectrodes for pumping electrolytes in microchannels are currently under research. In this letter we demonstrate theoretically an enhancement in the performance of arrays of microelectrodes subjected to travelling wave potentials. Net fluid velocity can increase up to 2.7 times when the electrodes are raised above the channel bottom, proving that the viscous friction on the walls between electrodes is a key factor to account for in the design of microelectrode arrays. Finally, we perform a comparison with previous results for the asymmetric step electrode array. It is found that the maximum velocity for the travelling wave array is roughly twice that for the asymmetric step array.