[foamWang]

Hi Alberto, Raagh, Juho, and others,

I am working on a particle cloud settling problem.
I wonder whether dynMixSmagorinsky can be added.
The single phase problem has been well addressed.
I would like to know if any advancement has been done and be happy to be the first user.

PS: Alberto, may I have a look at your code?

Thanks in advance.

Roro

[alberto]

Originally Posted by foamWang

Hi Alberto, Raagh, Juho, and others,

I am working on a particle cloud settling problem.

How dense (average volume fraction)?

I wonder whether dynMixSmagorinsky can be added.

Yes, it can be added very easily re-using the work done for single-phase flows by OpenFOAM developers.

PS: Alberto, may I have a look at your code?

I can send you my code, but it wasn't ported to a recent release of OpenFOAM. You can either email me, or, if you want a newer version, get in touch with Juho.

Best,

[vonboett]

Hello Alberto and all particle settling Foamers,

I am quite interested in twoPhaseLESEulerFoam, too. I have so far used a modified interDyMFoam solver to simulate freeface fluid structure interactions of shallow landslides with flexible protection barriers in my PhD thesis, but since this is done i would like to work on erosion around piles in hyperconcentrated turbulent flows, as they occur during flood events. Could you imagine simulating particles in a turbulent Herschel-Bulkley rheology flow using twoPhaseEulerFoam? Please let me know if I can contribute.

Regards,

Albrecht
(Albrecht v. Boetticher, albrecht.vonboetticher[at]wsl.ch, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Züricherstrasse 111, CH-8903 Birmensdorf)

[alberto]

Originally Posted by vonboett

Hello Alberto and all particle settling Foamers,

I am quite interested in twoPhaseLESEulerFoam, too. I have so far used a modified interDyMFoam solver to simulate freeface fluid structure interactions of shallow landslides with flexible protection barriers in my PhD thesis, but since this is done i would like to work on erosion around piles in hyperconcentrated turbulent flows, as they occur during flood events. Could you imagine simulating particles in a turbulent Herschel-Bulkley rheology flow using twoPhaseEulerFoam? Please let me know if I can contribute.

Hi,

the solution algorithm should not have extreme difficulties to deal with non-Newtonian problems.

In OpenFOAM 2.0.0 twoPhaseEulerFoam implements the PIMPLE algorithm, which makes it more stable. If you use the kinetic theory of granular flows, the treatment of the particle pressure is still explicit, and this makes the solution less stable in dense regions.

You'll have to add the non-Newtonian model, but there should be no difficulty in managing large values of the viscosity (it's similar to what happens in a granular flow in the frictional regime, and there the algorithm, once the particle pressure is treated implicitly, works fine).

Best,

[vonboett]

Hi Alberto,

thanks for these advices, the mixture of LES with non-Newtonian models causes discussions from a physical point of view, but the implementation works fine in interFoam and I think I'll run some simple experiments with a flume for validation. I will start writing the proposal in fall so that the project could start in next summer. But instead of dealing with the particles in twoPhaseEulerFOAM I think I will use InterFOAM and link it with an external discrete finite element code that traces the particles, and allows for complex bindings between the particles which makes it possible to simulate fishing nets as well as the foundation of piles in eroding granular material with different grain sizes. I thought about feeding the particle position and velocity to InterFOAM, together with a particle radius. Then finding all cells that ly within the particle radius and then work through the resulting actio and reactio forces, applied to the flow and to the particle. I will post the first trial tests when ready...

[alberto]

Originally Posted by vonboett

Hi Alberto,

thanks for these advices, the mixture of LES with non-Newtonian models causes discussions from a physical point of view, but the implementation works fine in interFoam and I think I'll run some simple experiments with a flume for validation. I will start writing the proposal in fall so that the project could start in next summer. But instead of dealing with the particles in twoPhaseEulerFOAM I think I will use InterFOAM and link it with an external discrete finite element code that traces the particles, and allows for complex bindings between the particles which makes it possible to simulate fishing nets as well as the foundation of piles in eroding granular material with different grain sizes. I thought about feeding the particle position and velocity to InterFOAM, together with a particle radius. Then finding all cells that ly within the particle radius and then work through the resulting actio and reactio forces, applied to the flow and to the particle. I will post the first trial tests when ready...

Good luck. It seems a very complicated problem. :-)

[GerhardHolzinger]

Are there news on twoPhaseEulerFoam and LES?

Who has worked that out and how difficult is this?
Will this combination be publicly available in the future?

[alberto]

Hi Gerhard,

if with LES you mean a Smagorinsky-type model for the continuous phase, the implementation is easy, and can be based on what is already available into OpenFOAM.

[yushiw]

Hi, all,

I am trying to run twoPhaseEulerFoam with one of the RSTM.
I am wondering if anyone has done this before or any instruction on how to modify the code?

thank you in advance,

yy

[alberto]

Originally Posted by yushiw

Hi, all,

I am trying to run twoPhaseEulerFoam with one of the RSTM.
I am wondering if anyone has done this before or any instruction on how to modify the code?

thank you in advance,

yy

You have to replace the k-epsilon implementation with the RSTM implementation for multiphase flows. The code does not rely on the turbulence models in the library, since you have to include the volume fraction.

Best,

[mohamed_]

hi all
I am new in Open FOAM and I am starting my work on LES of an evaporating two-phaseflow with LE approach.I built my code for the liquid phase.and i want to know if it is possible to find in OF for the gas phase a LES code solves the filtered compressible Navier-Stokes equations and if i can add my source term in the code and integrate the gas solver with my liquid solver.

mohamed

[alberto]

Originally Posted by mohamed_

hi all
I am new in Open FOAM and I am starting my work on LES of an evaporating two-phaseflow with LE approach.I built my code for the liquid phase.and i want to know if it is possible to find in OF for the gas phase a LES code solves the filtered compressible Navier-Stokes equations and if i can add my source term in the code and integrate the gas solver with my liquid solver.

mohamed

Hi, OpenFOAM has compressible LES solvers. You might want to take a look at rhoPimpleFoam.

[mohamed_]

thanks alberto for your help , what about the integration between LES gas solver and my liquid solver ?

[alberto]

Originally Posted by mohamed_

thanks alberto for your help , what about the integration between LES gas solver and my liquid solver ?

I do not know enough about your solver to comment on this. Is your solver written in OpenFOAM? What kind of coupling do you need?

Alberto

[mohamed_]

Originally Posted by alberto

I do not know enough about your solver to comment on this. Is your solver written in OpenFOAM? What kind of coupling do you need?

Alberto

my solver written in fortran 90 and there is no problem to written in c++ .
the coupling (i need u, v,T,roh from LES solver & export the conductive heat flux to it at each time step )

[alberto]

This should not be too difficult: you can simply create an interface between the two codes. If you want to do things more cleanly, you probably should take a look at the Lagrangian solver already present in OpenFOAM, which includes heat and mass transfer too (see the combustion / diesel) solvers.

[mohamed_]

Originally Posted by alberto

This should not be too difficult: you can simply create an interface between the two codes. If you want to do things more cleanly, you probably should take a look at the Lagrangian solver already present in OpenFOAM, which includes heat and mass transfer too (see the combustion / diesel) solvers.

thanks alberto for your help

[yushiw]

Thank you very much for your reply, Alberto.

I am trying the standard kepsilon model for now but the simulation is very unstable. I have to limit my Courant Number below 0.2 otherwise it will diverge.
I am using limitedLinearV 1 for my convective terms and I am wondering if anyone has similar experience or any idea to improve it?

Thank you.

[mohamed_]

hi alberto ,
I start to look at rhoPimpleFoam solver , I need your help to find some tutorial about governing equations and how to run the solver, Thanks for your help.

mohamed

[alberto]

Hi,

the governing equations for rhoPimpleFoam are the continuity, momentum and energy equation of a compressible fluid. You can refer to Ferziger and Peric and Hirsch books, for example.

For the tutorials, a starting point are the examples here

~/OpenFOAM/OpenFOAM-2.1.x/tutorials/compressible/rhoPimpleFoam/

If you have questions, just ask on the forum :-)