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-   -   Slurry (sand water) flow in twoPhaseEulerFlow possible? (http://www.cfd-online.com/Forums/openfoam-solving/93697-slurry-sand-water-flow-twophaseeulerflow-possible.html)

jochemvandenbosch October 24, 2011 08:14

Slurry (sand water) flow in twoPhaseEulerFlow possible?
 
Hi everybody,

As a part of my MSc. thesis I am trying to model a slurry flow (sand/water) in OpenFOAM (for different geometries). I heard that i could best use the twoPhaseEulerFlow solver for this problem, however I have found only examples regarded pneumatic conveying in combination for this solver.
Can this solver also be used for a liquid/solid interface. Some specifics of my research are:
Turbulent flow (Re>>2300)
Pipe flow
Sand (2600kg/m^3), water mixture
Concentrations ranging from 10 to 40%
Medium fine sand, d50 approximately 300-600 micrometer

I am particularly interested in the pressure drop allong the length of the pipe. Is the twoPhaseEulerFlow the right solver to use and do you think I would have to adjust this solver. If it is not the one to use, which one should I use.

Thanks so much in advance!!!

Best regards!

alberto October 26, 2011 11:27

Yes, it should work. The code might present some instability if particles pack. Please, search the forum for discussions on the topic.

jochemvandenbosch October 27, 2011 03:21

Hi Alberto. Thanks for your response. I did some research (mostly on this forum) and for now I've decided to go with settlingFoam instead of twoPhaseEulerFoam, since the first is based on the drift-flux model, which I already have some experience with (is taught by my university). Also packing might occur (not sure). settlingFoam seems more appropiate for this task (although it doesn't provide means to simulate a sliding bed...).
Do you know of any thesis' that use settlingFoam to simulate slurry flow.

Thanks in advance & best regards,

alberto October 27, 2011 14:26

OK. Just keep in mind that the algebraic slip model (mixture model) is valid for relatively low particle concentrations and it might have limitations on the Stokes number.

BTW, I am working on slurry flow with my (heavily) modified version of twoPhaseEuler, and it is working fairly well.

jochemvandenbosch October 31, 2011 05:25

Hi Alberto, thanks for your tips. About the mixture model for low concentration, my professor (Cees van Rhee) used this model in het PhD thesis (on the sedimentation process in a trailing suction hopper dredger) succesfully for concentrations up to 40% (sand in water). What are your thoughts about this (what do you consider a high concentration?)?

Best regards,

ps. what kind of slurry flow are you working on, sand/water? And open-channel flow or pipeflow?

alberto October 31, 2011 11:46

Hi Jochem,

as long as the hypotheses behind the model are satisfied, you can use it. Remember that the mixture model is derived making quite strong assumptions:

- Local equilibrium among the phases, which limits the validity to low Stokes numbers

- Mixture hypothesis, which limits the property ratio of the phases

When it comes to fluid-particle flows, the mixture model is suggested in case the particle loading is "low". How low depends on the flow conditions, but since you do not consider particle-particle interactions, I would say ~10%. You find applications with much higher concentrations, however. There are doubts on the validity of the model under those conditions however.

I deal with slurry flow in ducts (high St number).

Best,

ali.m.1 December 18, 2015 08:09

Hi both,

In regards to the original question, is there an Euler-Euler solver available for particle/fluid flow? I'm using twoPhaseEulerFoam, but I don't like how I have to include temperature. The openFoam website says the model is incompressible, but it clearly isn't.

Any help is appreciated!

regards

alberto December 26, 2015 00:03

This has been addressed in reactingTwoPhaseEulerFoam (OF 3.0.x or -dev from the Foundation). You can set phases to be isothermal, and the energy equation won't be solved.

The model can be compressible or incompressible, depending on how you set the thermodynamic properties of the phases (see fluidisedBed tutorial, where the solid phase is incompressible).

ali.m.1 January 5, 2016 09:58

Thanks for your reply Alberto. I'm using 2.3.x, so Iíll upgrade.

I'm planning on combining this solver with DPMFoam, have you heard of anything else like this? Combining two solvers I mean... For example solver A running in the top of the domain, and solver B running in the bottom of the domain. I think it will be tricky, but not impossible.

Your help is appreciated!

regards

tidusuper91 March 18, 2016 12:27

Quote:

Originally Posted by alberto (Post 578688)
This has been addressed in reactingTwoPhaseEulerFoam (OF 3.0.x or -dev from the Foundation). You can set phases to be isothermal, and the energy equation won't be solved.

The model can be compressible or incompressible, depending on how you set the thermodynamic properties of the phases (see fluidisedBed tutorial, where the solid phase is incompressible).

Dear @alberto,
How do I set the phases isothermal? I tried to set up the diameterModel as isothermal and minIter for the energy equation to 0 but it stills continue to solve energy for both phases.

ali.m.1 March 24, 2016 08:23

Ruben, see below:
http://www.cfd-online.com/Forums/ope...tml#post580432

tidusuper91 March 30, 2016 05:27

Quote:

Originally Posted by ali.m.1 (Post 591473)

Thank you. I also managed to make it shutting down even with bare twoPhaseEulerFoam and reported it in the thread you're quoting. =)


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