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NODAL FORCES - ENFO 2
- Thread starter Doodler3D
- Start date
Hard to tell what could cause this. What kind of values do you expect? It's hard for us to give any real advice without knowing loading conditions, boundary conditions and coordinate systems used. A plot of nodal forces along a line without further information is not sufficient information.
- Thread starter
- #3
@petb, ENFOZ should sum up to 3000 lbf. This is based on WA Weaver's paper on weld throat estimation.
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jkupka84
Mechanical
- Apr 15, 2014
- 40
@Doodler3D so possible reason is bad connection via shared topology? I observe this behaviour from time to time but it usually ends by rigid body motion not wrong results.
What is your final solution? Do you create a model from scratch or you do a glued connection?
Best regards
JK
What is your final solution? Do you create a model from scratch or you do a glued connection?
Best regards
JK
- Thread starter
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1
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jkupka84
Mechanical
- Apr 15, 2014
- 40
@Doodler3D
Hello there, sorry for such late response. Maybe I found where do you do a mistake. Please verify my assumption. Did you make Component with Share Topology in SpaceClaim?
[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1629195899/tips/2021-08-17_121809_qum7bx.tiff[/url]
The result look fine by me.
[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1629195910/tips/2021-08-17_122036_snlyba.tiff[/url]
Best regards
JK
Hello there, sorry for such late response. Maybe I found where do you do a mistake. Please verify my assumption. Did you make Component with Share Topology in SpaceClaim?
[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1629195899/tips/2021-08-17_121809_qum7bx.tiff[/url]
The result look fine by me.
[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1629195910/tips/2021-08-17_122036_snlyba.tiff[/url]
Best regards
JK
rickfischer51
Mechanical
Try selecting only the elements on the part with the hole with the forces. If all the elements are selected, the reactions sum to zero, as your plot shows. Thats why it works for bonded contact and not shared topography. And dont forget SPOINT at the centroid of the weld group so your moments are accurate.
Rick Fischer
Principal Engineer
Argonne National Laboratory
Rick Fischer
Principal Engineer
Argonne National Laboratory
- Thread starter
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rickfischer51
Mechanical
You can have shared topology, but you have to select the elements on the edge of one of the parts to be joined by the weld, and then select the nodes on that edge. Put a local CSYS at the origin of the weld group, and set the SPOINT as the global coordinates of the local CSYS. Set the RSYS to the local CSYS, then do FSUM,RSYS. The resulting reaction forces will be in the correct csys and the reaction moments will be around the centroid of the weld group.
Rick Fischer
Principal Engineer
Argonne National Laboratory
Rick Fischer
Principal Engineer
Argonne National Laboratory
- Thread starter
- #16
@jkupka84 the default is to use shared topology/continuous mesh, and avoid the use of MPCs and contact, especially large models.
Rick, now its clear, define a local co-ordinate system while extracting unaveraged nodal forces for sizing welds.
Rick, now its clear, define a local co-ordinate system while extracting unaveraged nodal forces for sizing welds.
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