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initial velocity field with a pressure difference

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Old   July 23, 2009, 04:20
Default initial velocity field with a pressure difference
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Sven Degner
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hi,

Im not really sure about my initial fields, and i hope everyone help me with this problem.
first of all I create a simple geometries.
For the next step I will initial my p and U fields
.
The problem now my velocity field is define by a pressure difference .

The question is that the correct definition, for this problem?

/************************************** p *************/
outlet
{
type fixedValue;
value uniform -50000;
}
inlet
{
type zeroGradient;
}
.
.
.
/************************************************** ***/

/************************************** U *************/
outlet
{
type zeroGradient;
}
inlet
{
type zeroGradient;
}
.
.
.
/************************************************** ***/
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Old   July 23, 2009, 04:59
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Julien Schaguene
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Hi,

I think there is something missing here.
If you want your flow to be defined by a pressure difference, you have to put fixedValue to outlet AND inlet, otherwise your domain is going to have a uniform relative pressure equal to -50000, and in theory no velocity...

For further precision, we'll need explanations on geometry, solver used...
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Old   July 23, 2009, 05:05
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Also, this seems to be the boundary condition - not actually the initial field? The initial condition can be set in the internalField, located above you boundaryField. For example internalField uniform <your-number>; .
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