Merging Ansys Geometry

[Stringmaker]

I have a number of parts (about 10) created in Ansys which are all part of an assembly. Initially I analyzed everything on a part by part basis. Now I would like to take the individual parts, import them all into the same database, and assemble them so to speak within Ansys so that I can analyze the system as one. Some parts are volumes and others are areas. Does anyone know what commands would be used for this or where in the documentation I can find some guidance? I've had minimal luck in my search thus far. Ultimately the assembled model will be comprised of solids and shells. Any help or input would be appreciated.

Thanks in advance!
-Brian

 

[Drej]

I think you need to look at ANSYS boolean operations if I understand you correctly (see help file: Modeling and Meshing> Chapter 5. Solid Modeling> 5.4. Sculpting Your Model with Boolean Operations). These operations deal with the glueing, overlapping, intersecting, adding, subtracting etc. etc. of lines, areas and volumes. If you have two solid entitites that need to be attached (or "assembled" as you've put it) then these are the operations to look at. Here is a snippet of the commands that you can use:

These PREP7 commands are used to perform Boolean operations on solid model entities.
AADD Adds separate areas to create a single area.
AGLUE Generates new areas by "gluing" areas.
AINA Finds the intersection of areas.
AINP Finds the pairwise intersection of areas.
AINV Finds the intersection of an area with a volume.
AOVLAP Overlaps areas.
APTN Partitions areas.
ASBA Subtracts areas from areas.
ASBL Subtracts lines from areas.
ASBV Subtracts volumes from areas.
ASBW Subtracts the intersection of the working plane from areas (divides areas).
BOPTN Specifies Boolean operation options.
BTOL Specifies the Boolean operation tolerances.
LCSL Divides intersecting lines at their point(s) of intersection.
LGLUE Generates new lines by "gluing" lines.
LINA Finds the intersection of a line with an area.
LINL Finds the common intersection of lines.
LINP Finds the pairwise intersection of lines.
LINV Finds the intersection of a line with a volume.
LOVLAP Overlaps lines.
LPTN Partitions lines.
LSBA Subtracts areas from lines.
LSBL Subtracts lines from lines.
LSBV Subtracts volumes from lines.
LSBW Subtracts the intersection of the working plane from lines (divides lines).
VADD Adds separate volumes to create a single volume.
VGLUE Generates new volumes by "gluing" volumes.
VINP Finds the pairwise intersection of volumes.
VINV Finds the intersection of volumes.
VOVLAP Overlaps volumes.
VPTN Partitions volumes.
VSBA Subtracts areas from volumes.
VSBV Subtracts volumes from volumes.
VSBW Subtracts intersection of the working plane from volumes (divides volumes).

Make sure you read the help file to ensure you know the difference between commands (say, between "adding" and "overlapping") before you start to assemble your model.

Alternatively of course, you can always "assemble" your model using contact. In most instances simple (linear) tied contact works very well.


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[Stringmaker]

Drej,
Thanks for the reply. I think my initial question was not asked properly and you're a step ahead of me. I'm wondering how do I take geometry from multiple databases and import the different geometries into one? For instance I have analyzed a circuit board and in another instance I did analysis of a component it mates onto in real life. How would I take these two separate geometries and import them both into one new database? Once I have the import done I feel very comfortable that I can move and mate them as necessary using booleans.

Thanks again for your help!

Best,
-Brian

 

[Drej]

Ok, that's easy. Just import each model one at a time using "file > Import > (choose your geometry type)". Remember for some types of geometry each model as you import it into ANSYS will be imported in the orientation it was exported from your CAD package, so you may need to play around with each geometry to get it into the correct orientation. Some types of geometry don't re-orientate the model, and it just comes in and placed at the 0,0,0 datum. Have a look for yourself and see when you import.


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[Stringmaker]

Drej,
I'm trying to import Ansys geometry (areas and lines) that I created within Ansys from existing databases into a new one. Nothing was generated using a CAD program and when I access the File->Import I don't see any options that allow me to import any sort of Ansys file such as a .db file extension. I'm hoping that I can prevent myself from having to reconstruct each part by hand again inside a new database now that I want to analyze these as an assembly instead of on an individual basis which I did before.

Thank you,
-Brian

 

[meshparts]

Hi,

just use the cdwrite and cdread commands. The cdwrite command is for saving solid geometry data. The cdread for reading it. The file format must be *.cdb for solid model geometry data. I don't think that it would work with *.db.

Regards,
Alex

 

[Stringmaker]

Thanks Alex! I will give this a shot.