Force FEMAP to write a single SPC1 card using "THRU" instead of one for each node?
Force FEMAP to write a single SPC1 card using "THRU" instead of one for each node?
(OP)
This is me being hyper picky, but assume I have a group of nodes that are sequential: "1001,2000,1"
It is evident that FEMAP is able to detect that they are sequential because when I select them, it shows exactly what I have above in the selection dialogue (i.e. 1001,2000,1) when I go to create a single point constraint (SPC).
But when I go to my .BDF file, it is written as one thousand individual SPC1 cards. Is there anyway to force FEMAP to write it as:
instead of:
???
It is evident that FEMAP is able to detect that they are sequential because when I select them, it shows exactly what I have above in the selection dialogue (i.e. 1001,2000,1) when I go to create a single point constraint (SPC).
But when I go to my .BDF file, it is written as one thousand individual SPC1 cards. Is there anyway to force FEMAP to write it as:
CODE -->
SPC1 1 456 1001 THRU 2000
instead of:
CODE -->
SPC1 1 456 1001 SPC1 1 456 1002 SPC1 1 456 1003 . . . SPC1 1 456 2000
________________________
FEMAP v11.1.0
MSC Nastran v2013





RE: Force FEMAP to write a single SPC1 card using "THRU" instead of one for each node?
or maybe to how FeMap writes a .bdf IF Nastran allows that format, which would surprise me.
another day in paradise, or is paradise one day closer ?
RE: Force FEMAP to write a single SPC1 card using "THRU" instead of one for each node?
________________________
FEMAP v11.1.0
MSC Nastran v2013
RE: Force FEMAP to write a single SPC1 card using "THRU" instead of one for each node?
another day in paradise, or is paradise one day closer ?
RE: Force FEMAP to write a single SPC1 card using "THRU" instead of one for each node?
You may wonder why I would have thousands and thousands of SPCs in my bdf. Here is what I have been doing. If I have solid elements in my model, which do not generally support DOF 456, as well has other elements (or MPC) in my model, which do support rotational DOF, I manually SPC out ALL of the nodes that belong to solid elements. Why the heck do I do this? Because I like to do it manually and keep AUTOSPC = YES so that I can use the grid point singularity table as a "bucket" to catch anything that I may have missed. This is me being hyper-aware of my constraints so that I can track down improper model grounding.
Now to be honest, I am relatively new to FEM/FEA (maybe 2 years of industry experience) and even newer to FEMAP/NASTRAN (about 3 months .. prior experience with ANSYS) ... so this could just be me being obsessive compulsive without any good reasoning. I welcome any feedback or thoughts people have on this. This is how I learn.
________________________
FEMAP v11.1.0
MSC Nastran v2013
RE: Force FEMAP to write a single SPC1 card using "THRU" instead of one for each node?
I like your non-use of auto-SPC ! of course you can use auto-SPC then check that all the created restraints don't generate large reactions.
another day in paradise, or is paradise one day closer ?
RE: Force FEMAP to write a single SPC1 card using "THRU" instead of one for each node?
Hi,
You can include this line in your analysis setting / Nastran BUlk Data Options / Start Text (Off):
SPC1 1 456 1001 THRU 2000
Give it a try without defining the constraints in Femap.
Hope this helps !
Seif Eddine Naffoussi, Stress Engineer
www.Innovamech.com
33650 Martillac û France
RE: Force FEMAP to write a single SPC1 card using "THRU" instead of one for each node?
You can remove rotational DOF from solid elements automatically in FEMAP without writing any SPC1 card, neither using PARAM,AUTOMPC,YES: the key is to use commnd "MODIFY > UPDATE OTHER > PERMANENT CONSTRAINTS" > select all nodes from solid elements and next select the DOF you want to remove:
If you PREVIEW your analysis you will see that not any SPC/CPC1 card exist, the DOF removed are part of the GRID card !!.
Best regards,
Blas.
~~~~~~~~~~~~~~~~~~~~~~
Blas Molero Hidalgo
Ingeniero Industrial
Director
IBERISA
48004 BILBAO (SPAIN)
WEB: http://www.iberisa.com
Blog de FEMAP & NX Nastran: http://iberisa.wordpress.com/
RE: Force FEMAP to write a single SPC1 card using "THRU" instead of one for each node?
@compositecurves - That's actually what I have been doing and what spawned my question. I know that sooner or later, we all have to manually edit our input decks. But for now, my line of thinking was that if I have to re-run a model with some adjustments, than I have to remember to update the model in FEMAP AND in the input deck. Giving myself 2 opportunities to make errors gives me great consternation ... but I guess I just have to get used to the idea and start being extra, EXTRA careful. Thanks for your input!
@Blas - Wow! I'll have to give this a try; it looks like it's exactly what I am looking for. I like the idea of doing the extra research to figure out to get FEMAP to generate a deck exactly the way I want to; this helps to eliminate extra opportunities for errors as I mentioned above.
________________________
FEMAP v11.1.0
MSC Nastran v2013
RE: Force FEMAP to write a single SPC1 card using "THRU" instead of one for each node?
another day in paradise, or is paradise one day closer ?