Mixing via thermocapillary generation of flow patterns inside a microfluidic drop

Cordero, María Luisa; Rolfsnes, Hans O.; Burnham, Daniel R.; Campbell, Paul A.; McGloin, David; Baroud, Charles N.

doi:10.1088/1367-2630/11/7/075033

Cited by 40 publications

(34 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In that vein, Song et al 3 have used a wavy microchannel to achieve passive homogenisation of droplets in less than 10 ms. An approximate model for this kind of mixing process was given by Stone and Stone. 78 A different approach was demonstrated by Cordero et al 79 who forced a periodic recirculation by creating a time-periodic Marangoni flow induced by alternating laser heating. Furthermore, Gunther et al 72 have shown that wall roughness may even be sufficient to induce chaotic mixing in some cases through slight deformations of the drop geometry.…”

Section: Flow Fields and Mixingmentioning

confidence: 99%

Dynamics of microfluidic droplets

2010

View full text Add to dashboard Cite

This critical review discusses the current understanding of the formation, transport, and merging of drops in microfluidics. We focus on the physical ingredients which determine the flow of drops in microchannels and recall classical results of fluid dynamics which help explain the observed behaviour. We begin by introducing the main physical ingredients that differentiate droplet microfluidics from single-phase microfluidics, namely the modifications to the flow and pressure fields that are introduced by the presence of interfacial tension. Then three practical aspects are studied in detail: (i) The formation of drops and the dominant interactions depending on the geometry in which they are formed.(ii) The transport of drops, namely the evaluation of drop velocity, the pressure-velocity relationships, and the flow field induced by the presence of the drop. (iii) The fusion of two drops, including different methods of bridging the liquid film between them which enables their merging.

show abstract

Section: Flow Fields and Mixingmentioning

confidence: 99%

Dynamics of microfluidic droplets

2010

View full text Add to dashboard Cite

show abstract

“…For droplets traveling within an unsteady flow (such as nano-or microdroplets currently under intensive investigation for their promise in processing single cells [25]), such elongation can be achieved by positioning the droplet at a hyperbolic trajectory location, whose control is therefore desirable. While the hyperbolic trajectory described above is exterior to the droplet, many droplet models in the literature themselves possess on the droplet's surface a saddle-like hyperbolic trajectory [26][27][28][29][30][31][32][33][34][35][36] whose motion influences intradroplet chaotic transport because its attached stable and unstable manifolds undergo nontrivial motion. There is currently only one method in the scientific literature which can control manifold paths [37], but it is limited to two-dimensional nearly steady flows with one-dimensional stable and unstable manifolds.…”

Section: Introductionmentioning

confidence: 99%

Accurate control of hyperbolic trajectories in any dimension

Balasuriya

Padberg‐Gehle

2014

Phys. Rev. E

View full text Add to dashboard Cite

The unsteady (nonautonomous) analog of a hyperbolic fixed point is a hyperbolic trajectory, whose importance is underscored by its attached stable and unstable manifolds, which have relevance in fluid flow barriers, chaotic basin boundaries, and the long-term behavior of the system. We develop a method for obtaining the unsteady control velocity which forces a hyperbolic trajectory to follow a user-prescribed variation with time. Our method is applicable in any dimension, and accuracy to any order is achievable. We demonstrate and validate our method by (1) controlling the fixed point at the origin of the Lorenz system, for example, obtaining a user-defined nonautonomous attractor, and (2) the saddle points in a droplet flow, using localized control which generates global transport.

show abstract

“…By scanning a nanoliter droplet with a heating laser beam along a two-dimensional pattern, Grigoriev et al (2006) induced chaotic mixing inside the droplet, through a combination of a bulk thermoconvective flow and an interface-driven thermocapillary flow. Cordero et al (2009) used an optocapillary microdroplet blocking scheme (see Fig. 8), combined with spatial and temporal light modulation techniques.…”

Section: Splitting Merging and Mixingmentioning

confidence: 99%