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 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
{
}
}

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

internalField uniform (0 0 0);

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

Outlet
{
}

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?

T

Quote:
 Originally Posted by alexeym (Post 478474) Hi, http://www.cfd-online.com/Forums/ope...-get-help.html Can you provide more details?

 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?

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.