6533b7d8fe1ef96bd126a407
RESEARCH PRODUCT
Gravity effects on mixing with magnetic micro-convection in microfluidics.
L. PuķinaAndrejs CēbersA. TatuļčenkovsGuntars Kitenbergssubject
ConvectionGravity (chemistry)Field (physics)BiophysicsFOS: Physical sciences02 engineering and technologyCondensed Matter - Soft Condensed Matter01 natural sciencesInstability010305 fluids & plasmasGravitationPhysics::Fluid Dynamics0103 physical sciencesGeneral Materials ScienceCritical fieldMixing (physics)PhysicsFluid Dynamics (physics.flu-dyn)Laminar flowSurfaces and InterfacesGeneral ChemistryMechanicsPhysics - Fluid Dynamics021001 nanoscience & nanotechnologySoft Condensed Matter (cond-mat.soft)0210 nano-technologyBiotechnologydescription
Mixing remains an important problem for development of successful microfluidic and lab-on-a-chip devices, where simple and predictable systems are particularly interesting. One is magnetic micro-convection, an instability happening on the interface of miscible magnetic and non-magnetic fluids in a Hele-Shaw cell under applied field. Previous work proved that Brinkman model quantitatively explains the experiments. However, a gravity caused convective motion complicated the tests. Here we first improve the experimental system to exclude the gravitational convective motion. Afterwards, we observe and quantify how gravity and laminar flow play an important role in stabilizing the perturbations that create the instability. Accordingly, we improve our theoretical model and perform linear analysis. Two dimensionless quantities explain the experimental observations of change in critical field needed for instability and characteristic size of the emerging pattern. Finally, we discuss the conditions at which gravity plays an important role in microfluidic systems.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2018-04-30 | The European physical journal. E, Soft matter |