[masoud.ravan]

Hi everyone,
I have a question about the Multi-Fluid VOF Model that would be accessible when the Eulerian Model is enabled in Ansys Fluent. According to Ansys Fluent help (17.5.19) “The multi-fluid VOF model provides a framework to couple the VOF and Eulerian multiphase models”. As others mentioned (Cerne et al.,2001; Strubelj and I. Tiselj, 2011; and some other published papers), in order to develop a coupled model, It’s necessary to choose a model to deal with both sharp and dispersed interface regimes and also deploy an appropriate switching criteria to recognize and distinguish these two interfaces and switch the solving approach. For example, one can choose the Mixture or Two-Fluid model for the dispersed interface regime and VOF or Level Set for the sharp interface regimes. I would be appreciated if anyone could give me more details about theory, equilibriums and switching criteria of Multi-Fluid VOF model.
Thanks in Advance

[Rohtiwari]

Hey,
Do you get any information or reference for the same?

[masoud.ravan]

Originally Posted by Rohtiwari

Hey,
Do you get any information or reference for the same?

Luckily YES!
This model could capture sharp interface between phases by using a special discretization scheme called the Compressive Advection Scheme. If you want more on this issue, see these two papers:

"Zwart, Philip J., Alan D. Burns, and Paul F. Galpin. "Coupled algebraic multigrid for free surface flow simulations." Proc. OMAE2007, San Diego, California, USA, June (2007): 10-15."

"Vallée, Christophe, et al. "Experimental investigation and CFD simulation of horizontal stratified two-phase flow phenomena." Nuclear Engineering and Design 238.3 (2008): 637-646."

[prasa]

Originally Posted by masoud.ravan

Luckily YES!
This model could capture sharp interface between phases by using a special discretization scheme called the Compressive Advection Scheme. If you want more on this issue, see these two papers:

"Zwart, Philip J., Alan D. Burns, and Paul F. Galpin. "Coupled algebraic multigrid for free surface flow simulations." Proc. OMAE2007, San Diego, California, USA, June (2007): 10-15."

"Vallée, Christophe, et al. "Experimental investigation and CFD simulation of horizontal stratified two-phase flow phenomena." Nuclear Engineering and Design 238.3 (2008): 637-646."

Hi,
I try to use Euler multi-fluid VOF method for solid particle (2700 kg/m3) flow in open channel with a fluid. Here all three phases are Eularian phases, and solid phase is considered as a granular phase.

I try to find the relevant equations, unfortunately i have not found good literature.

In generally, three Euler phases have three momentum equations, and VOF model as one single momentum equation. Please help me to understand, how these equations coupling together.

Thanks,
Prasanna.

[masoud.ravan]

Originally Posted by prasa

Hi,
I try to use Euler multi-fluid VOF method for solid particle (2700 kg/m3) flow in open channel with a fluid. Here all three phases are Eularian phases, and solid phase is considered as a granular phase.

I try to find the relevant equations, unfortunately i have not found good literature.

In generally, three Euler phases have three momentum equations, and VOF model as one single momentum equation. Please help me to understand, how these equations coupling together.

Thanks,
Prasanna.

Do you want to capture interface and see the interaction of solid particles with fluid simultaneously?

[prasa]

Originally Posted by masoud.ravan

Do you want to capture interface and see the interaction of solid particles with fluid simultaneously?

Hi Masoud

I want to see the effect of particle to the flow depth (free surface between fluid and solid). In other word, how particle influence to the flow depth.

Regards,
Prasa.

[masoud.ravan]

Originally Posted by prasa

Hi Masoud

I want to see the effect of particle to the flow depth (free surface between fluid and solid). In other word, how particle influence to the flow depth.

Regards,
Prasa.

Hi Prasa
As I found, you want to analyze free surface changes due to existing particles (Tell me if I'm wrong). So you have a multi-scale flow. I have mentioned two papers about MultiFluid VOF method in this thread, Did you read them? These two papers could give you some basic knowledge of this method.