[lourencosm]

How can I access to the gravity vector "g" from swak4foam?

Tried this but "g" is not recognised by the swakExpression

getG
{
    type executeIfObjectExists;
    readDuringConstruction true;

    objectName g;
    checkType true;
    objectType uniformDimensionedVectorField;
    objectShouldExist false;

    functions
    {
        loadG
        {
            type readGravitation;
        }
    }
   outputControlMode	timeStep; //timeStep
   outputInterval  1;
   verbose			true;
}

gz
{
	type 			swakExpression;
	valueType		patch;
	patchName		inlet;

	expression	"mag(g)*pos().z";
	accumulations	( average )

	outputControlMode	timeStep; //timeStep
	outputInterval  1;
	verbose			true;
}

I get this error:

[0] --> FOAM FATAL ERROR: 
[0]  Parser Error for driver PatchValueExpressionDriver at "1.5" :"field g not existing or of wrong type"
"mag(g)*pos().z"
      ^
------|

Context of the error:


- From dictionary: /home/lourenco/currentRuns/ihFoam_aw/2_codeTest/v01_shiFly/10x1f_mB3L_s02_functionsTest/system/controlDict.functions.gz
  Evaluating expression "mag(g)*pos().z"
[0] 
[0] 
[0]     From function parsingValue
[0]     in file lnInclude/CommonValueExpressionDriverI.H at line 1204.
[0] 
FOAM parallel run exiting
[0] 
[1] 
[1] 
[1] --> FOAM FATAL ERROR: 
[1]  Parser Error for driver PatchValueExpressionDriver at "1.5" :"field g not existing or of wrong type"
"mag(g)*pos().z"
      ^
------|

Context of the error:


- From dictionary: IOstream.functions.gz
  Evaluating expression "mag(g)*pos().z"
[1] 
[1] 
[1]     From function parsingValue
[1]     in file lnInclude/CommonValueExpressionDriverI.H at line 1204.
[1] 
FOAM parallel run exiting
[1] 
[2] 
[2] 
[2] --> FOAM FATAL ERROR: 
[2]  Parser Error for driver PatchValueExpressionDriver at "1.5" :"field g not existing or of wrong type"
"mag(g)*pos().z"
      ^
------|

Context of the error:


- From dictionary: IOstream.functions.gz
  Evaluating expression "mag(g)*pos().z"
[2] 
[2] 
[2]     From function parsingValue
[2]     in file lnInclude/CommonValueExpressionDriverI.H at line 1204.
[2] 
FOAM parallel run exiting
[2] 
[3] 
[3] 
[3] --> FOAM FATAL ERROR: 
[3]  Parser Error for driver PatchValueExpressionDriver at "1.5" :"field g not existing or of wrong type"
"mag(g)*pos().z"
      ^
------|

Context of the error:


- From dictionary: IOstream.functions.gz
  Evaluating expression "mag(g)*pos().z"
[3] 
[3] 
[3]     From function parsingValue
[3]     in file lnInclude/CommonValueExpressionDriverI.H at line 1204.
[3] 
FOAM parallel run exiting
[3] 
[4] 
[4] 
[4] --> FOAM FATAL ERROR: 
[4]  Parser Error for driver PatchValueExpressionDriver at "1.5" :"field g not existing or of wrong type"
"mag(g)*pos().z"
      ^
------|

Context of the error:


- From dictionary: IOstream.functions.gz
  Evaluating expression "mag(g)*pos().z"
[4] 
[4] 
[4]     From function parsingValue
[4]     in file lnInclude/CommonValueExpressionDriverI.H at line 1204.
[4] 
FOAM parallel run exiting
[4] 
Expression gz : --> FOAM Warning : 
    From function ConcretePluginFunction<DriverType>::exists
    in file lnInclude/ConcretePluginFunction.C at line 121
    Constructor table of plugin functions for PatchValueExpressionDriver is not initialized

What am I missing?

Thank you,
Lourenço

[Scram_1]

Hey Lourenco!
I'm facing a similar problem where OF is not recognizing gravity when I use groovyBC in parallel. Did you find a work around to this problem?

Thanks!!

Best,
Sriram

[lourencosm]

Hey Scram_1,

I didn't. I did a workaround...
I was using this in a postProcessing swakExpression of a case with gravitational acceleration not aligned with the z axis. In the end I introduced the orientation manually in the swakExpression.

Sorry! Please write here if you find the solution.

Good luck,
Lourenço