Hood91
Aerospace
- Sep 3, 2015
- 5
Hi everyone,
I'm currently working on a project that involves creating a very large DFEM to the level where we intent to model rivets as CBUSH elements. Due to the size of the model, the amount of rivets will be in the 1000's. We have created a macro in excel that can take two lists of corresponding nodes we can then input the bdf in to the macro and it creates suitable properties for the CBUSH using the Huth formula whilst also writing the lines for CBUSH's to put back into the final bdf.
So here's the problem. Currently, the only way I can think to get the two list of nodes is to manually create the node ID's at each of the fastener positions, e.g. 1,2,3, mesh the geometry and then equivalence keeping the ID's I've created. This should work fine, but obviously for 1000's of locations is a lot of tedious work! There are fixed points at the locations of the rivets on the geometry so nodes will automatically be created there using automesh, but that's the only other way to know where the rivet locations are after meshing. I'm using Hypermesh to create geometry and mesh, but also have use of PATRAN.
Does anyone have any ideas if it's possible to somehow automate the process to somehow get a macro or something to identify which nodes should have the CBUSH connections? I should note that I'm using midsurface geometry, meshing with quads. Obviously it'd be a lot easier if the nodes where coincident, but alas they're not!
Thanks in advance for any thoughts you may have on the matter.
Matt
I'm currently working on a project that involves creating a very large DFEM to the level where we intent to model rivets as CBUSH elements. Due to the size of the model, the amount of rivets will be in the 1000's. We have created a macro in excel that can take two lists of corresponding nodes we can then input the bdf in to the macro and it creates suitable properties for the CBUSH using the Huth formula whilst also writing the lines for CBUSH's to put back into the final bdf.
So here's the problem. Currently, the only way I can think to get the two list of nodes is to manually create the node ID's at each of the fastener positions, e.g. 1,2,3, mesh the geometry and then equivalence keeping the ID's I've created. This should work fine, but obviously for 1000's of locations is a lot of tedious work! There are fixed points at the locations of the rivets on the geometry so nodes will automatically be created there using automesh, but that's the only other way to know where the rivet locations are after meshing. I'm using Hypermesh to create geometry and mesh, but also have use of PATRAN.
Does anyone have any ideas if it's possible to somehow automate the process to somehow get a macro or something to identify which nodes should have the CBUSH connections? I should note that I'm using midsurface geometry, meshing with quads. Obviously it'd be a lot easier if the nodes where coincident, but alas they're not!
Thanks in advance for any thoughts you may have on the matter.
Matt
