I'm using fluent meshing mode to create mesh. When I create surface mesh, I get the error message:
error: arg(3rd) out of range in substring
error object: 6
Can anyone help me to find the possible reason?
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watertight geometry workflow is used
I wonder if it's the Student version hitting the cell cap. Increase the smaller cell size by a fair bit and see if it'll work. Then try and refine. You're capped at 512k cells, so if you have that many vertices I suspect you're creating too big a mesh.
I increased the minimum cell size to 5, it still has this message. I'm using academic license.
I used these settings to generate mesh on my old computer using ANSYS 2019 R2, it worked.
But after I transfer the model to a new computer and use the same settings, the error message came up. The ansys version on the new computer is 2019R3.
Meshing didn't change that much. Were you using Student on the old computer? Given the number of surface facets I don't see how it could work on Student.
I'm using academic license on both computers. the problem may be caused by different versions of ansys. I have tried other fluent mesh files. Sometimes when I just open the mesh file and click on create surface mesh, the error message shows up:
Error: arg(3rd) out of range in substring
Error Object: 6
Error: Illegal Variant cast from bool to class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >, data: False
Error Object: ()
Teaching or research? Also, what's the new computer & folder (full path) called?
computer name: Untaroiu-2
fluent : C:\Program Files\ANSYS Inc\v195\fluent\ntbin\win64
Not sure then: can you mesh a simple cube?
yes, it works with a simple cube.
So it's model dependent. Pick a big cell size (ie far larger than will resolve the flow features) and try again. I don't care about mesh quality, I want to see what the cell count is.
Hi, I tried different settings for a simple cube. It also has errors some time. It seems like when a local size is added, the error message comes up.
What's the local sizing set to? Also how big is the box?
The box is 21x21x30 mm, Local sizing: 5,
Weird. That should give you about 4-6 cells on each edge. I assume the guide "cubes" are a sensible size?
Hi, what are guide cubes ?
The green cube (they're red on my display). They show the expected cell size, you'll typically see two sizes for a min & max. Can you turn off proximity: I wonder if you've created an impossible set of conditions for the mesh. Ie the surface mesh can't be true for both the local & surface sizing.
The proximity is turned off, but still the same message. The error occurs when reading the temporary .sf file. When I remove the local sizing, it works with the same setting under 'create surface mesh'.
If I make the local sizing on all the surfaces same as the minimum size under 'create surface mesh', What possible changes can local sizing add to the mesh? Is the local sizing information stored in .sf file ? Is it possible to view the details in .sf file ?
The sizing on the surface will be a function of the size functions and local sizing. Given it's a cube curvature is unlikely to do much, so sizing will be set by proximity. You can probably get the size function out from the tree (not the workflow) but I'll leave that for you to find: I rarely use that feature.
thank you for the explanation. The errors occurs when I transfer files to a different computer (same settings), so I doubt it might be caused by software installation.
But do you have suggestions on how to set element size on a specific surface in fluent meshing mode ?
I'm new to fluent meshing, Do you recommend to use workflow in fluent for mesh generation ?
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