A unified model is presented for the velocity of discrete droplets in microchannels actuated by surface tension modulation. Specific results are derived for the cases of electrowetting on dielectric (EWOD), dielectrophoresis (DEP), continuous electrowetting (CEW), and thermocapillary pumping (TCP). This treatment differs from previously published works by presenting one unified analytic model which is then simply applied to the specific cases of EWOD, CEW, DEP and TCP. In addition, the roles of equiliubrium contact angle and contact angle hysteresis are unambiguously described for each method. The model is shown to agree with experimental and theoretical results presented previously, predicting fluid velocities for a broad range of applications in digitized microfluidics.
Volume Subject Area:
Microelectromechanical Systems
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