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 oldroydB model and VOF for free surface calculation. I appreciate any help 
Hi
I am also interested in
Hi
I am also interested in this topic and I am willing to work on this. 
Hello,
any progress in this
Hello,
any progress in this subject? I've done some simulations using OldroydB models, FENEtype models, etc. with a selfdeveloped 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 (highweissenberg 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 
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 powerlaw 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 
Hello OpenFOAM experts
I ha
Hello OpenFOAM experts
I have been trying to implement the Maxwell and OldroydB 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 
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 nonNewtonian fluids. AIChE 53 (2007), 18611878]. Usually, these fluids behave like beasts  I'd start with a simple (unsteady) shear flow to show the solver is working. br Stefan Radl 
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 
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. NonNewtonian Fluid Mech. 93 (2000) 287–314 Effect of a highresolution differencing scheme on finitevolume predictions of viscoelastic flows M.A. Alves , F.T. Pinho, P.J. Oliveira Kerstin 
Hi,
The source stability pr
Hi,
The source stability problem is extended infsup (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 weaklycompressible viscoelastic liquids flow: finite element/volume schemes Journal of NonNewtonian Fluid Mechanics Volume 126, Issues 23, 10 March 2005, Pages 123143 ". 
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
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