Setting specific values to a vector field component

manalis · September 30, 2015, 11:07

Hello to everyone,

As a beginner in OpenFOAM, I have a problem in compiling a modified version of a standard solver. Specifically, I have created a "volVectorField" in the respective "CreateFields.H" file, which is actually a velocity field. My problem is that I can't set the "Uy" component of this vector to a value that comes from a scalar variable Vcalc, which is calculated before. In other words I would like to set

Code:

Uy = Vcalc

.

I tried to find similar topics in the forum but I couldn't (or at least I didn't realize it!). Any help would be very appreciated.

Best regards.

Montague · October 1, 2015, 15:40

When constructing your vector field you can construct a temporary volVectorField and multiply it by your scalar or scalarField. This would be done in the solver file E.G. icoFoam.c Vcalc must have the same dimensions as myU since your temp variable will be dimensionless.

In createFields.H you will have to initialize myU following the same convention as the other variables. You will also have to supply myU to the '0' folder with appropriate boundary conditions.

Code:

volVectorField temp
    (
    	IOobject
		(
			"temp",
			runTime.timeName(),
			mesh,
			IOobject::NO_READ,
			IOobject::NO_WRITE
		),
	        mesh,
		vector(0,1,0)
    );
myU = temp*Vcalc;

Hope this helps

,
Jim

manalis · October 9, 2015, 13:03

Thank you James. It helped a lot!

Best regards

September 30, 2015, 11:07	Setting specific values to a vector field component	#1
manalis New Member ... Join Date: Jun 2013 Posts: 19 Rep Power: 12	Hello to everyone, As a beginner in OpenFOAM, I have a problem in compiling a modified version of a standard solver. Specifically, I have created a "volVectorField" in the respective "CreateFields.H" file, which is actually a velocity field. My problem is that I can't set the "Uy" component of this vector to a value that comes from a scalar variable Vcalc, which is calculated before. In other words I would like to set Code: Uy = Vcalc . I tried to find similar topics in the forum but I couldn't (or at least I didn't realize it!). Any help would be very appreciated. Best regards.

October 1, 2015, 15:40		#2
Montague New Member James Montague Join Date: Jan 2014 Location: Vermont, United States Posts: 7 Rep Power: 12	When constructing your vector field you can construct a temporary volVectorField and multiply it by your scalar or scalarField. This would be done in the solver file E.G. icoFoam.c Vcalc must have the same dimensions as myU since your temp variable will be dimensionless. In createFields.H you will have to initialize myU following the same convention as the other variables. You will also have to supply myU to the '0' folder with appropriate boundary conditions. Code: volVectorField temp ( IOobject ( "temp", runTime.timeName(), mesh, IOobject::NO_READ, IOobject::NO_WRITE ), mesh, vector(0,1,0) ); myU = temp*Vcalc; Hope this helps , Jim

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October 9, 2015, 13:03		#3
manalis New Member ... Join Date: Jun 2013 Posts: 19 Rep Power: 12	Thank you James. It helped a lot! Best regards