Assigning loads to surfaces / automated boundary conditions

Dear all,

I am building a hex mesh with cgx and I want to automate the meshing process for mesh refinement studies. I already wrote a parametrized fbd script for mesh generation, but I still have to assign the boundary conditions manually using qadd in the cgx gui after meshing. I am looking for a zero-click-approach, so-to-say.

  1. Is there a way to assign loads to surfaces rather than element faces? (gmsh-style)

or, alternitavely,

  1. Can I automatically assign boundary conditions, maybe by mapping them from a file with the same geometry but a different mesh?

I already found that the enq command makes it possitble to select specific elements after meshing, but this only seems to work well for simple geometries.
I also see the option of creating different sets using seta after meshing…
Just before I do that, I just want to make sure there is no easier way that I overlooked.

I appreciate any hints.

The number 2 could be done by means of *SUBMODEL card, check in the CCX documentation.

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Thanks, I will look into that!

CGX has a lot of options to perform the task. Im my example collection at github these are used in nearly all cases.

Topology-based selection: If you have a surface A00F in CGX, then the following code writes aa ccx surface definition (set of element faces) to a file

seta load s A00F  
comp load do
comp load do
send load abq sur

Then include the file load.sur in your ccx input deck and use it for contact or pressure application

Location-based selection: As you already mentionded, another way is to create location-based sets of nodes with command “enq” and expand (“complete”) them to element face sets using “comp” as above.

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Thanks a lot, the topology-based selection is exactly what I was looking for!