Topology and shape optimization of induced-charge electro-osmotic micropumps

TL;DR

This study employs topology optimization to design dielectric geometries that significantly enhance induced-charge electro-osmotic flow in micropumps, demonstrating the critical influence of shape and topology on system performance.

Contribution

It introduces a novel application of topology optimization with an artificial design field to improve ICEO micropump efficiency by optimizing dielectric solid geometries.

Findings

Optimized geometries increase electro-osmotic flow rate.

Topology and shape critically affect ICEO performance.

Validated designs outperform conventional configurations.

Abstract

For a dielectric solid surrounded by an electrolyte and positioned inside an externally biased parallel-plate capacitor, we study numerically how the resulting induced-charge electro-osmotic (ICEO) flow depends on the topology and shape of the dielectric solid. In particular, we extend existing conventional electrokinetic models with an artificial design field to describe the transition from the liquid electrolyte to the solid dielectric. Using this design field, we have succeeded in applying the method of topology optimization to find system geometries with non-trivial topologies that maximize the net induced electro-osmotic flow rate through the electrolytic capacitor in the direction parallel to the capacitor plates. Once found, the performance of the topology optimized geometries has been validated by transferring them to conventional electrokinetic models not relying on the artificial design field. Our results show the importance of the topology and shape of the dielectric solid in ICEO systems and point to new designs of ICEO micropumps with significantly improved performance.