| | |
| | |
Stat |
Members: 3667 Articles: 2'599'751 Articles rated: 2609
07 February 2025 |
|
| | | |
|
Article overview
| |
|
Effects of viscoelasticity on droplet dynamics and break-up in microfluidic T-Junctions: a lattice Boltzmann study | Anupam Gupta
; Mauro Sbragaglia
; | Date: |
1 Aug 2015 | Abstract: | The effects of viscoelasticity on the dynamics and break-up of fluid threads
in microfluidic T-junctions are investigated using numerical simulations of
dilute polymer solutions at changing the Capillary number ($mbox {Ca}$), i.e.
at changing the balance between the viscous forces and the surface tension at
the interface, up to $mbox{Ca} approx 3 imes 10^{-2}$. A Navier-Stokes (NS)
description of the solvent based on the lattice Boltzmann models (LBM) is here
coupled to constitutive equations for finite extensible non-linear elastic
dumbbells with the closure proposed by Peterlin (FENE-P model). We present the
results of three-dimensional simulations in a range of $mbox{Ca}$ which is
broad enough to characterize all the three characteristic mechanisms of breakup
in the confined T-junction, i.e. ${it squeezing}$, ${it dripping}$ and ${it
jetting}$ regimes. The various model parameters of the FENE-P constitutive
equations, including the polymer relaxation time $ au_P$ and the finite
extensibility parameter $L^2$, are changed to provide quantitative details on
how the dynamics and break-up properties are affected by viscoelasticity. We
will analyze cases with ${it Droplet ~Viscoelasticity}$ (DV), where
viscoelastic properties are confined in the dispersed (d) phase, as well as
cases with ${it Matrix ~Viscoelasticity}$ (MV), where viscoelastic properties
are confined in the continuous (c) phase. Moderate flow-rate ratios $Q approx
{cal O}(1)$ of the two phases are considered in the present study. Overall, we
find that the effects are more pronounced in the case with MV, as the flow
driving the break-up process upstream of the emerging thread can be sensibly
perturbed by the polymer stresses. | Source: | arXiv, 1508.0141 | Services: | Forum | Review | PDF | Favorites |
|
|
No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.
|
| |
|
|
|