A new generalised model of the electrowetting of microfluids has been proposed. Instead of the conventional Young–Lippmann formula, dynamic minimising of the total energy of system which is superposition of capillary free energy and electric energy has been utilised to calculate the contact angle as indicator of wetting behaviour. The change of interfacial energy of liquid/solid interface and change in relative permittivity of solution in the presence of colloid particles have also been considered in the developed model. The model predicts that contact angle saturation decreases in the presence of colloid particles both in DC and AC conditions. The model also predicts that the reduction of contact angle by applying potential is higher in the case of TiO₂/water microfluidic system which is in agreement with experimental data reported in literature.

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Errata

An Erratum has been published for this content:

Corrigendum: Prediction of the contact angle of colloids and microfluids during electrowetting

Prediction of the contact angle of colloids and microfluids during electrowetting

References

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