Difference between revisions of "Main ContribExamples/OscillatingFixedValue"
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(New page: Searching the tutorials I couldn't find an example of how to use this type of boundary condition, so I've created a very small and simple tutorial. Basically, the setup requires the defini...) |
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refValue uniform (1 0 0); | refValue uniform (1 0 0); | ||
} | } | ||
| − | The above setup enables to specify a boundary condition for an entire patch that varies in time as: | + | The above setup enables to specify a velocity boundary condition for an entire patch that varies in time as: |
<math>1+amplitude\cdot\sin\left(2\pi\cdot frequency\cdot t\right)</math> | <math>1+amplitude\cdot\sin\left(2\pi\cdot frequency\cdot t\right)</math> | ||
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[[Media:bcOscilating.tar.gz|Sample OpenFOAM case]] - it applies to {{VersionInfo}}{{Version1.5}} | [[Media:bcOscilating.tar.gz|Sample OpenFOAM case]] - it applies to {{VersionInfo}}{{Version1.5}} | ||
| + | |||
| + | |||
| + | ---- | ||
| + | Update - it applies to {{VersionInfo}}{{Version2.1}} | ||
| + | |||
| + | As from OpenFOAM 2.1.x, the dictionary for this boundary condition should read as | ||
| + | myPatch | ||
| + | { | ||
| + | type oscillatingFixedValue; | ||
| + | value uniform 0; // Initialization value | ||
| + | refValue uniform ''refV''; // Reference value for oscillation | ||
| + | offset ''offset''; // Oscillation mean value offset | ||
| + | amplitude constant ''Amp''; // Amplitude of oscillation | ||
| + | frequency constant ''freq''; // frequency | ||
| + | } | ||
| + | for a given scalar field. If applied to vector field, value, offset and refValue should be modified accordingly. This dictionary specifies an oscillating boundary condition of a given scalar, for an entire patch, as: | ||
| + | |||
| + | <math> \textrm{\textit{refV}} \cdot \left( 1.0 + \textrm{\textit{Amp}} \cdot \sin \left(2\pi\cdot \textrm{\textit{freq}}\cdot t\right)\right) + \textrm{\textit{offset}}</math> | ||
| + | ---- | ||
Latest revision as of 23:57, 28 January 2013
Searching the tutorials I couldn't find an example of how to use this type of boundary condition, so I've created a very small and simple tutorial. Basically, the setup requires the definition of 4 parameters:
inlet
{
type oscillatingFixedValue;
amplitude 0.5;
frequency 0.2;
refValue uniform (1 0 0);
}
The above setup enables to specify a velocity boundary condition for an entire patch that varies in time as:
Sample OpenFOAM case - it applies to Valid versions: 
Update - it applies to Valid versions: 
As from OpenFOAM 2.1.x, the dictionary for this boundary condition should read as
myPatch
{
type oscillatingFixedValue;
value uniform 0; // Initialization value
refValue uniform refV; // Reference value for oscillation
offset offset; // Oscillation mean value offset
amplitude constant Amp; // Amplitude of oscillation
frequency constant freq; // frequency
}
for a given scalar field. If applied to vector field, value, offset and refValue should be modified accordingly. This dictionary specifies an oscillating boundary condition of a given scalar, for an entire patch, as:
