Partner: Volkert van Steijn

Delft University of Technology (NL)

Ostatnie publikacje
1.Korczyk P.M., van Steijn V., Błoński S., Zaremba D., Beattie D.A., Garstecki P., Accounting for corner flow unifies the understanding of droplet formation in microfluidic channels, Nature Communications, ISSN: 2041-1723, DOI: 10.1038/s41467-019-10505-5, Vol.10, No.1, pp.2528-1-9, 2019

Streszczenie:

While shear emulsification is a well understood industrial process, geometrical confinement in microfluidic systems introduces fascinating complexity, so far prohibiting complete understanding of droplet formation. The size of confined droplets is controlled by the ratio between shear and capillary forces when both are of the same order, in a regime known as jetting, while being surprisingly insensitive to this ratio when shear is orders of magnitude smaller than capillary forces, in a regime known as squeezing. Here, we reveal that further reduction of—already negligibly small—shear unexpectedly re-introduces the dependence of droplet size on shear/capillary-force ratio. For the first time we formally account for the flow around forming droplets, to predict and discover experimentally an additional regime—leaking. Our model predicts droplet size and characterizes the transitions from leaking into squeezing and from squeezing into jetting, unifying the description for confined droplet generation, and offering a practical guide for applications.

Afiliacje autorów:

Korczyk P.M.-IPPT PAN
van Steijn V.-Delft University of Technology (NL)
Błoński S.-IPPT PAN
Zaremba D.-IPPT PAN
Beattie D.A.-University of South Australia (AU)
Garstecki P.-Institute of Physical Chemistry, Polish Academy of Sciences (PL)
200p.
2.van Steijn V., Korczyk P.M., Derzsi L., Abate A.R., Weitz D.A., Garstecki P., Block-and-break generation of microdroplets with fixed volume, BIOMICROFLUIDICS, ISSN: 1932-1058, DOI: 10.1063/1.4801637, Vol.7, pp.024108-1-8, 2013

Streszczenie:

We introduce a novel type of droplet generator that produces droplets of a volume set by the geometry of the droplet generator and not by the flow rates of the liquids. The generator consists of a classic T-junction with a bypass channel. This bypass directs the continuous fluid around the forming droplets, so that they can fill the space between the inlet of the dispersed phase and the exit of the bypass without breaking. Once filled, the dispersed phase blocks the exit of the bypass and is squeezed by the continuous fluid and broken off from the junction. We demonstrate the fixed-volume droplet generator for (i) the formation of monodisperse droplets from a source of varying flow rates, (ii) the formation of monodisperse droplets containing a gradation of solute concentration, and (iii) the parallel production of monodisperse droplets.

Słowa kluczowe:

droplet generator, droplets, microfluidics

Afiliacje autorów:

van Steijn V.-Delft University of Technology (NL)
Korczyk P.M.-IPPT PAN
Derzsi L.-Institute of Physical Chemistry, Polish Academy of Sciences (PL)
Abate A.R.-University of California (US)
Weitz D.A.-Harvard University (US)
Garstecki P.-Institute of Physical Chemistry, Polish Academy of Sciences (PL)
35p.

Abstrakty konferencyjne
1.Korczyk P.M., Van Steijn V., Błoński S., Kowalewski T.A., Garstecki P., Mechanism of generation of droplets in a T-junction for low capillary numbers, XXI FMC, XXI Fluid Mechanics Conference, 2014-06-15/06-18, Kraków (PL), pp.117, 2014

Słowa kluczowe:

microfluidics, lab on a chip, droplets, T-junction

Afiliacje autorów:

Korczyk P.M.-IPPT PAN
Van Steijn V.-Delft University of Technology (NL)
Błoński S.-IPPT PAN
Kowalewski T.A.-IPPT PAN
Garstecki P.-Institute of Physical Chemistry, Polish Academy of Sciences (PL)