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-   -   simpleFoam for WATER (http://www.cfd-online.com/Forums/openfoam-solving/130885-simplefoam-water.html)

vut March 5, 2014 11:49

simpleFoam for WATER
 
Hi,

I want to simulate a water flow inside an injector by simpleFoam.

I change nu => 1e-6 in constant/transportProperties.

But the run failed!

Do you have any explaination?

Thanks

T

alexeym March 6, 2014 05:54

Hi,

http://www.cfd-online.com/Forums/ope...-get-help.html

Can you provide more details?

vut March 6, 2014 12:54

simpleFoam - pressure driven water flow inside injector
 
Hi,

Here are the details I changed: BC and transportProperties in constant/

1/ The first thing is the BC:

for p
==================================

internalField uniform 0;

boundaryField
{
Inlet
{
type fixedValue;
value uniform 100;
// = P_inlet/rho_water = 100 000 Pa / 1000 kg/m3, is it right?
// or should I give 100 000 Pa instead?
}

Outlet
{
type fixedValue;
value uniform 0;
}

Symmetry
{
type symmetryPlane;
}

Wall
{
type zeroGradient;
}
}



for U
==================================

internalField uniform (0 0 0);

boundaryField
{
Inlet
{
type pressureInletVelocity;
value uniform (0 0 0);
}

Outlet
{
type zeroGradient;
}

Symmetry
{
type symmetryPlane;
}

Wall
{
type fixedValue;
value uniform (0 0 0);
}
}

2/ The second one is transportProperties

transportModel Newtonian;

nu nu [ 0 2 -1 0 0 0 0 ] 1e-06;

// for the kinematic viscosity of water, right?



I really appreaciate your advices.

T




Quote:

Originally Posted by alexeym (Post 478474)


alexeym March 6, 2014 13:07

If you take a look at the units of pressure, they are m^2*s^-2, i.e. pressure/density, so you are right about value.

Several things you forgot to mention:
0. Can you show the output of "But the run failed!"?
1. Are you sure that your mesh is OK?
2. What's in your fvSolution?
3. What's in your fvSchemes?
4. What's in your controlDict?

In general "But the run failed!" can mean anything.

vut March 7, 2014 04:46

Alexey,

The error I made was stupid: The value of epsilon in the initial conditions is wrong. That's why the simulation ran for several iterations and then stopped due to big discrepancies between time steps.

I really appreciate your attention and your time on my question.

Hope this very "stupid experience" useful for new OpenFoamer like me!

Have a nice day!

T


Quote:

Originally Posted by alexeym (Post 478585)
If you take a look at the units of pressure, they are m^2*s^-2, i.e. pressure/density, so you are right about value.

Several things you forgot to mention:
0. Can you show the output of "But the run failed!"?
1. Are you sure that your mesh is OK?
2. What's in your fvSolution?
3. What's in your fvSchemes?
4. What's in your controlDict?

In general "But the run failed!" can mean anything.



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