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-   -   VOF simulation of a viscoelastic fluid (http://www.cfd-online.com/Forums/openfoam-solving/58204-vof-simulation-viscoelastic-fluid.html)

sinah March 25, 2007 05:41

Hi everyone I am trying to si
 
Hi everyone
I am trying to simulate the free surface of a viscoelastic fluid I intend to use oldroyd-B model and VOF for free surface calculation. I appreciate any help

billy March 25, 2007 11:52

Hi I am also interested in
 
Hi

I am also interested in this topic and I am willing to work on this.

sradl June 9, 2007 05:50

Hello, any progress in this
 
Hello,

any progress in this subject? I've done some simulations using Oldroyd-B models, FENE-type models, etc. with a self-developed code. I just want to warn you: simulation of viscoelastic fluids is NOT straight forward and additional numerical problems arise, i.e. you have to stabilize the simulation otherwise you will get a blow up (high-weissenberg number problem).

So if you have any clue, how to include in OpenFOAM, I could assist with some expertise in (complicated) stabilizing simulations (actually, there are a lot of techniques, we have used simply a dissipation term to smooth the stress field).


Cheers
Stefan

sinah June 9, 2007 14:21

hi stefan For my project I've
 
hi stefan
For my project I've done some experimental works with CMC solution this solution can adequately be modeled with power-law like equations although it shows viscoelastic effects, anyway I have added some of these models to openfoam and gained some coding experience(It was some coding practice not viscoelastic simulation;)). But I am still very interested in that topic and if you like we can cooprate.
good luck
sina

rvajapey November 30, 2008 19:31

Hello OpenFOAM experts I ha
 
Hello OpenFOAM experts

I have been trying to implement the Maxwell and Oldroyd-B models to study the viscoelastic flow phenomenon. I have stability problems as told by Mr. Stefan Radl. I would like to know more about these problems. Any help would be appreciated.

thank you veru much

Raghu

sradl December 1, 2008 03:16

Dear Raghu, I can send you
 
Dear Raghu,

I can send you my work if you like, or you can look into my aiche paper [Radl, Tryggvason, Khinast. Flow and mass transfer of fully resolved bubbles in non-Newtonian fluids. AIChE 53 (2007), 1861-1878].

Usually, these fluids behave like beasts - I'd start with a simple (unsteady) shear flow to show the solver is working.

br
Stefan Radl

caw December 1, 2008 04:19

Dear Stefan, i would be int
 
Dear Stefan,

i would be interessted in your work as well :-)
Regarding these fluids as beasts is probably the appropriate description..

Best regards
Christian

kerstin December 3, 2008 03:23

Hi, The stability problems
 
Hi,

The stability problems come from the fact, that these "damn stresses" don't have a diffusion term in the PDE. Diffusion makes life so much easier ;-)

This paper gives an overview about higher order methods for FVM method and viscoelastic models...maybe of some help?

J. Non-Newtonian Fluid Mech. 93 (2000) 287–314
Effect of a high-resolution differencing scheme on
finite-volume predictions of viscoelastic flows
M.A. Alves , F.T. Pinho, P.J. Oliveira

Kerstin

ibrahim December 15, 2008 19:53

Hi, The source stability pr
 
Hi,

The source stability problem is extended inf-sup (LBB) conditions. Introducing extra stress terms to governing equations includes extra compatibility conditions. Accuracy of velocity gradients has significant impact on stability/accuracy of schemes. We addressed these issues in our article "Computation of incompressible and weakly-compressible viscoelastic liquids flow: finite element/volume schemes
Journal of Non-Newtonian Fluid Mechanics
Volume 126, Issues 2-3, 10 March 2005, Pages 123-143 ".

commonyue November 24, 2010 14:03

Hi dear sradl, i am working on the viscoelastic fluid, and need to write the code by myself, however, i have not got any clue by now, i wonder could you please send me your work on this kind of complex fluid. thanks so much, i am really appreciate your kind help. Best Regards.Li


Quote:

Originally Posted by sradl (Post 186061)
Dear Raghu,

I can send you my work if you like, or you can look into my aiche paper [Radl, Tryggvason, Khinast. Flow and mass transfer of fully resolved bubbles in non-Newtonian fluids. AIChE 53 (2007), 1861-1878].

Usually, these fluids behave like beasts - I'd start with a simple (unsteady) shear flow to show the solver is working.

br
Stefan Radl


santiagomarquezd November 25, 2010 12:02

Hi, this thread might be useful:

http://www.cfd-online.com/Forums/ope...interfoam.html

Regards.


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