[Dozer_94]

Hi everyone,

I have a tricky, maybe even impossible question.

The goal is to mesh a quarter (axisymmetric) cylinder with fixed length and radius L and R.
The cylinder wall is divided into N patches of equal length L/N (see the attached figure for N=5).

Right now I create vertices and blocks manually. You can imagine that if N becomes large, I can spend the entire day making a single mesh. Therefore, I'd like to parametrize N and let the script do it for me. The problem is that loops are not a thing in the BlockMeshDict (at least not to my knowing).

I know about m4 but the documentation is marginal. What is the best approach here?

Thanks in advance!

[dlahaye]

Does this help: https://github.com/damogranlabs/classyBlocks
https://damogranlabs.com/2020/02/cla...for-blockmesh/

[GerhardHolzinger]

If you only want to use variable parameters, and don't need the entire magic that Python-scripting has to offer, you can also use OpenFOAM's on-board tools, i.e., using variables in dictionaries, the code-stream magic.

A parametric blockMeshDict from the tutorials

[Dozer_94]

Does this help: https://github.com/damogranlabs/classyBlocks
https://damogranlabs.com/2020/02/cla...for-blockmesh/

I downloaded the git and tried to run the "from_points" example, but python throws me a "raise AttributeError(f"Unknown edge type: {self.type}") on line 132 of primitives.py.

I installed and prioritized python 3.8 so not really sure where the error is originating from.

If you only want to use variable parameters, and don't need the entire magic that Python-scripting has to offer, you can also use OpenFOAM's on-board tools, i.e., using variables in dictionaries, the code-stream magic.

A parametric blockMeshDict from the tutorials

I am considering this as well:

radius 			0.0005;
Len 			0.001;
nSegments 		5.0;

radHalfAngle    #calc "degToRad($halfAngle)";
y               #calc "$radius*sin($radHalfAngle)";
minY            #calc "-1.0*$y";
z               #calc "$radius*cos($radHalfAngle)";
segmentLength	#calc "$Len / $nSegments";

codeStream
#{
	std::array<float, $nSegments> lenarray;
	for (int i=1;i<$nSegments;i++)
	{
		lenarray[i] = $segmentLength*i;
	}
#};

Passing variables like "nSegments" into the codestream works fine, but how exactly can you return variables or other data like "lenarray" back to the regular code?