| Jamill1283 |
March 12, 2024 10:16 |
2D Axisymmetric Mesh Not Working for Custom STL Multiphase Geometry
3 Attachment(s)
Dear Foamers,
I'm facing an issue with a multiphase flow simulation that involves modeling a liquid ligament in air. The geometry of the ligament, which is custom-designed using CAD software, has been exported to an STL file for this purpose.
My objective is to simulate this specific geometry in a 2D axisymmetric manner. However, I'm encountering a problem when the simulation is set up with a 2D mesh (having a mesh count of 1 in the z-direction); the liquid phase, which has a volume fraction of 1, does not appear correctly in the simulation. Interestingly, when I increase the mesh count in the z-direction to a higher number, the liquid's shape is accurately represented.
My blockmesh is as below;
Code:
scale 0.001;
blockWidth #eval "3";
ligamentSize #eval "0.5";
theta #eval "45.0 / 8";
arcLocZ #eval "($blockWidth) * sin(degToRad($theta))";
arcLocY #eval "($blockWidth) * cos(degToRad($theta))";
nArcLocZ #eval "-1*$arcLocZ";
ligArcLocZ #eval "($ligamentSize) * sin(degToRad($theta))";
ligArcLocY #eval "($ligamentSize) * cos(degToRad($theta))";
smallArcLocZ #eval "($blockWidth) * sin(degToRad($theta/2))";
smallArcLocY #eval "($blockWidth) * cos(degToRad($theta/2))";
smallLigArcLocZ #eval "($ligamentSize) * sin(degToRad($theta/2))";
smallLigArcLocY #eval "($ligamentSize) * cos(degToRad($theta/2))";
vertices
(
(0 0 0)
(10 0 0)
(10 $blockWidth 0)
(0 $blockWidth 0)
(0 $arcLocY $arcLocZ)
(10 $arcLocY $arcLocZ)
);
blocks
(
hex (0 3 4 0 1 2 5 1) (100 100 1) simpleGrading (1 1 1) //the issue is here
);
edges
(
);
patches
(
patch outlet
(
(2 5 1 1)
)
);
boundary
(
front
{
type wedge;
faces
(
(0 1 5 4)
(0 1 2 3)
);
}
ligament
{
type symmetry;
faces
(
(3 4 0 0)
);
}
external
{
type wall;
faces
(
(3 4 5 2)
);
}
axis
{
type empty;
faces
(
(0 1 1 0)
);
}
);
mergePatchPairs
(
);
Setfields as below;
Code:
defaultFieldValues
(
volScalarFieldValue alpha.phase1 0
volVectorFieldValue U (0 0 0)
);
regions (
surfaceToCell {
file "./constant/fluidStruct/ligament108.stl";
outsidePoints ((0.008 0.00025 0));
includeInside true;
includeOutside false;
includeCut true;
nearDistance -1;
curvature -100;
fieldValues (
volScalarFieldValue alpha.phase1 1
);
}
);
I'm seeking advice or solutions to ensure that the liquid phase is properly visualized while maintaining the simulation in a strictly 2D axisymmetric setup. Any insights or suggestions would be greatly appreciated.
Attached are visuals for 3D, problem for 2D mesh and zipped STL files;
Attachment 98919
Attachment 98920
Attachment 98921
Thank you in advance for your assistance.
Jamil |
