[alberto]

The version of twoLiquidMixingFoam in OpenFOAM 2.0 already uses PIMPLE. A tutorial was added today to 2.0.x (in git repository). Maybe take a look.

Best,

[gwierink]

Hi Tanay,

It would be helpful to post the compile error. But just guessing from

Originally Posted by Tanay

surfaceScalarField muEff ("muEff", (alpha1*mu1 + (scalar(1)-alpha1)*mu2));
volScalarField rho ("rho", (alpha1*rho1 + (scalar(1)-alpha1)*rho2));
surfaceScalarField rhoIntoPhi ("rhoIntoPhi", rho*phi);

it seems that at least one of the problems is that you're trying to assign a volScalarField (rho) to something that is a surfaceScalarField (rhoIntoPhi). You can make rho into a surfaceScalarField for example by:

surfaceScalarField muEff ("muEff", (alpha1*mu1 + (scalar(1)-alpha1)*mu2));
volScalarField rho ("rho", (alpha1*rho1 + (scalar(1)-alpha1)*rho2));
surfaceScalarField rhof = fvc::interpolate(rho);
surfaceScalarField rhoIntoPhi ("rhoIntoPhi", rhof*phi);

Hope that is of any help

EDIT: Whoops, missed Alberto's post. Well, hope it is helpful anyway

[okroud]

Originally Posted by Tanay

Here's the fvSchemes file if anyone wishes to view it-
ddtSchemes
{
default Euler;
}

gradSchemes
{
default Gauss linear;
grad(U) Gauss linear;
grad(muEff) Gauss linear;
grad(p_rgh) Gauss linear;
}

snGradSchemes
{
default corrected;
}

divSchemes
{
default none;
div(phi,U) Gauss limitedLinearV 1;
div(phi,k) Gauss limitedLinear 1;
div(phi,epsilon) Gauss limitedLinear 1;
div(phi,R) Gauss limitedLinear 1;
div(R) Gauss linear;
div(phi,nuTilda) Gauss limitedLinear 1;
div((nuEff*dev(grad(U).T()))) Gauss linear;
div(phi,alpha1) Gauss limitedLinear 1;
div(phi) Gauss limitedLinear 1;
div(rhoPhi,U) Gauss limitedLinear 1;
div(rho*phi,U) Gauss limitedLinear 1;
}

It's long ago, but do you still know why you have set
div((nuEff*dev(grad(U).T()))) Gauss linear;
And not limitedLinear 1 like all the other divSchemes. I know Gauss limitedLinear 1 exactly doesn't work (which is actually my problem), but isn't there a similar Scheme like limitedLinearV1 oder limitedLinear phi that works for div((nuEff*dev(grad(U).T())))?

[balkrishna]

According to the documentation , OpenFOAM doc

A limitedLinear scheme based on a flux phi with  is specified as default by phi = 1.

In ur definition, "div((nuEff*dev(grad(U).T()))) " there is no phi involved.

Probably , thats why Gauss limited linear doesnt work.

[carlosfloar]

Hi, I'm a master student who works about the mixing of two liquids in batching transport in a long pipes. I need to use a moving mesh because the high computational cost involved in the solutión of the entire domain. I want to use openFOAM for the solution of that problem specificaly employing the solver twoliquidmixingFoam. ¿It is possible to do?

thanks in advance for your help.

[ziemowitzima]

What kind of flow, are u planning to model ? Turbulent one, what is your Re ?
Do you mean ADAPTIVE MESH or MOVING mesh (changing geometry of the domain).
Both are possible. Did you look in this forum ?

Best

[carlosfloar]

I try to model a turbulent flow with Reynolds about 40000, I need to use moving mesh because the extension of the pipe, too many km and my interest is centered in the mixed fluid. At the moment I use a libraries written in c++ to attempt to solve this problem but I want to use OpenFOAM to solve it. ¿Anybody can help me with this? please, documentation, examples, tutorials...

[m.Chrsitiano]

Hi everyone,

How do I know what equations that twoLiquidMixingFoam uses?
For exemple, if I set no turbulence model (laminar), where is the laplacian term in the UEqn? And where the solver uses the kinematic viscosity (nu)?

Any replay would be very helpful, since I've just started using OpenFOAM.

Best regards!

[ziemowitzima]

Hi,
In the folder "system" in the file:
turbulenceProperties
you can set desired turbulence model. If you choose: laminar,
then standard N-S equations will be solved without any turbulence model, namely in the U eqn:
fvVectorMatrix UEqn
(
fvm::ddt(U)
+ fvm::div(phi, U)
+ turbulence->divDevReff(U)
);
the diffusion term
turbulence->divDevReff(U)
will be "replaced" by :
laplacian(nu,U)
where nu is your viscosity

if you choose e.g.:
simulationType RASModel;
then you have to have one more file in "system":
RASproperties
then in
turbulence->divDevReff(U)
corresponding turbulence model will be solved

see some of the examples in the tutorial/run/.../cases

[m.Chrsitiano]

Thank you very much! It was very enlightening!

Now make sense to me.
One more thing, about transport equation, where am I able to find it? Where is the file that it is writing?

Thank you very much again for your attention!

[ziemowitzima]

every solver is located at:
/opt/openfoam210/applications/solvers

or sth similar depending what version of OF and what OS you have.

see
http://openfoamwiki.net/index.php/Main_Page
and
http://openfoamwiki.net/index.php/IcoFoam

best

[m.Chrsitiano]

Thanks for the answer, that will be a nice help for me to work on.

[carlosfloar]

hi
I want to ask about the alphaDiffusionEqn.H file, in that file what's the meaning of the second line in:

fvm::ddt(alpha1)
- fvc::ddt(alpha1)
- fvm::laplacian
(
volScalarField("Dab", Dab + alphatab*turbulence->nut()),
alpha1
)
I think the meaning of the first line, fvm::ddt(alpha1) is (((rho_P*alpha1_P)^n)-((rho_P*alpha1_P)^o))/(Delta t)
it's this right? and, the second line?
please help me!!

[carlosfloar]

hi, I'm working in the implementation of Dynamic mesh in twoLiquidMixingFoam solver, I'm stuck at the moment, I try to use InterDyMFoam for a guide but don't obtain any results....any suggestions?

[carlosfloar]

I want to simulate a parcel composed of two fluids moving with the mean flow velocity, I try to implement DyM twoLiquidMixingFoam, but when I try to simulate a case the delta of time begins to decrease until it finally stops the solution ... I use a Courant=0.1 ,I initially tested on lockForExchange with boundary conditions fixedValue=0 on the walls ..... any suggestions?

[m.Chrsitiano]

Hello everyone,

How can i implement the LES model in the solver twoLiquidMixingFoam?

Thank you very much!

[m.Chrsitiano]

Hey guys,

Nobody know how to setup the solver to LES?

Another thing is, how do i change the numerical schemes in the fvSchems file? For exemple, the InterpolationSchemes?

Please, i would be very greatful for any replay.

Thank you in advance,

Christiano.

[carlosfloar]

Hi, I implemented the funcionality of dynamic mesh in the solver twoLiquidMixingFoam to solve the mixing of two fluids in a pipeline tracking a control volume of the domain large enough so that the interface between the two liquids is always contained therein. I ran tests with both sovers, twoLiquidMixingFoam and "twoLiquidMixingDyMFoam" but when comparing the amount of liquid that is mixed, it is rather more with the solver twoLiquidMixingDyMFoam. I use the same configuration in both solvers, the same fvSchemes, fvSolution, etc. anyone can help me with the Dynamic Mesh error?

[m.Chrsitiano]

Hello again people,

I was wondering...

How do you guys do to calculate the front velocity from a gravity current simulation?

[himanshu28]

Hi ziemowitzima,

your reply was useful but since there are two fluids and in the transport property file we specify kinematic viscosity of both the fluid,hence my question is which fluid kinematic viscosity will be used to solve the UEqn.

will be weighted same as density ----> rho = rho_1*alpha1 +rho_2*(1-alpha_1)
as there are nothing being mentioned on this part.

Thank you

Originally Posted by ziemowitzima

Hi,
In the folder "system" in the file:
turbulenceProperties
you can set desired turbulence model. If you choose: laminar,
then standard N-S equations will be solved without any turbulence model, namely in the U eqn:
fvVectorMatrix UEqn
(
fvm::ddt(U)
+ fvm::div(phi, U)
+ turbulence->divDevReff(U)
);
the diffusion term
turbulence->divDevReff(U)
will be "replaced" by :
laplacian(nu,U)
where nu is your viscosity

if you choose e.g.:
simulationType RASModel;
then you have to have one more file in "system":
RASproperties
then in
turbulence->divDevReff(U)
corresponding turbulence model will be solved

see some of the examples in the tutorial/run/.../cases