An Active Silicon Micromixer for μTAS Applications

Flow regimes and mass transfer characteristics in static micromixers

“…The observed effects cannot be determined definitely 4 or it is not possible to distinguish between chaotic laminar splitting and turbulent effects 5,6 . In many applications external forces like mechanical, pneumatic or ultrasonic vibrations 3,7,8 enhance the mixing process.…”

Liquid–liquid mixing enhancement rules by microbubbles in three typical micro-mixers

“…To the best of our knowledge, the present studies on gas enhanced liquid-liquid mixing process are mostly related to the aqueous solution's experiment, which is operated at low viscosity (μ$ 1 mPa s) and low flow rate ratios, defined as R¼Q A /Q B , (Ro10) (Long et al, 2009;Woias et al, 2000). Fig.…”

“…The passive enhancing method (Long et al, 2009;Schönfeld et al, 2004;Zhang et al, 2010) mainly utilizes the energy from pumps and improves mixing by enhancing relative movement of fluid particles, which results in complex microchannel structure as well as possible dead volume. The active enhancing method, in contrast, is working with the help of extra energy input, such as ultrasound (Yaralioglu et al, 2004), piezoelectrically vibrating (Woias et al, 2000), electric field (Oddy et al, 2001), pressure pulse (Glasgow and Aubry, 2003) etc. Other than these direct energy input approaches, the introduction of inert fluid is another simple but effective method to intensify mixing process.…”

A magnetic microstirrer and array for microfluidic mixing

“…In such time-dependent two-dimensional flows, chaos can occur and be used to improve the efficiency of mixing. Several fluid actuation methods have been demonstrated, including heat convection [13], differential pressure [14]- [17], ultrasonic or piezoelectric actuation [18]- [21], vapor pneumatic power [22], [23], magnetic actuation [24], [25] and electrokinetic (EK) pressure [26]. One important advantage of the active mixers is that they can be activated on-demand.…”