Learning Forum

[WolfgangNeil]

I'm facing errors (image below) while updating certain design points using both Parameters Correlation and RSO within the Design Exploration toolbox.

DesignXplorer error.JPG

[Rob]

We're not permitted to open attachments, so please have another try.
If it's only certain design points, try and do the update manually. Typically errors occur when geometry gets twisted/changes topology (ie bits get chopped off) or the mesher can't cope with the new shape based on the previous settings.

[WolfgangNeil]

The screenshot for the error messages:-
I've tried to insert the failing iterations of the DOE as design points in Parameter Set and tried to update locally but the same issue persists.
Can you please help me out?

[Rob]

What's different about the geometry?

[WolfgangNeil]

I've modelled a cuboidal geometry in DM. For the DOE, the length, width and height are the input parameters.

[Rob]

What dimensions are in the failed case, and what mesh settings did you use?

[WolfgangNeil]

I've created a new WB file with the same geometry. Right now I'm not getting any errors with geometry file attachment as per the screenshot I had shared earlier.
However, my observations are while performing the DOEs: -
1) For allowed value as "Any" for input parameters, the DOE is completed unhindered.
2) For allowed value as "Manufacturable" for input parameters, upon defining the distinct values, I'm getting an error for one DP for CCD type due to an un-converged solution.
Dimensions for failed DP: 793.5 x 345 x 1449 mm
Further, I've tried to solve the DP separately by importing this DP into the parameter set. However, it failed to solve.
# Mesh setting: Linear element order with sizing (hard behaviour) and multi-zone method.

[Rob]

Hard sizing and geometry parameters can be a problem if the geometry change breaks the sizing or forces a poor mesh. I'm not sure what a "linear element order" is, unless it's a Mechanical term? will know if it is - I drive Fluent CFD.

[WolfgangNeil]

I'll try with some changes to the meshing.
In Mechanical, mesh elements can be created without mid-side nodes (linear element, Hex8) or with mid-side nodes (quadratic element, Hex20).

[Rob]

Thanks for explaining. I knew about the mid-side nodes but not what the "normal" cells were called. In CFD we use more maths and just the Hex8, Tet4 and Poly"n" cells.