In hypermesh, while creating the flexible bodies
i wanted to use CMSMETH card CBN and CB Method
Now i wanted to know, will there be any difference in stiffness matrix in CBN and CB method?
Awaiting reply
Thank you
Hi,
the CB and CC methods are used for generating flexible bodies for use with some Multibody dynamics solvers, like MotionSolve. The CBN method can be used to generate CMS superelement information for some third-party solvers
ok sir, but i am using third party solver after converting into the flex body in which it used CB method
so some stiffness difference is coming..!
i want to know the difference so that i can use the sacling factor in that third party solver and get accurate results
help me with this
thank you
@LOKESH KATARI
Here is some theory about CBN from OptiStruct. You can search for generalized Craig Bampton method for CB
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Sir can u help in creating flexible body in hypermesh ??
what inputs and outputs cards should use
Thank You
Is it for MBD?
If yes, Please check this tutorial OS-T: 1930 Generating Flexible Body for use in MotionSolve
Sir i didnt get you where to check that OS-T:1930
i can see only MV-
Which version of HyperWorks are you using?
13 sir
Sir after using these model reduction methods
how do we know this model is DOF decreased or not?
I think CB comes with free free and constrained but CBN is not.
13.0 is very old. You can search for the tutorial with same title
while creating flexible bodies in optistruct for simpack
i activated CBN and gave UB_FREQ 20 but i am getting 127modes and fbi file around 12GB
i need only 40 modes. how to decrease those modes?
Please provide NMODES and try again.
yes sir i tried still its showing more number
i am doing it for chassis sir
When i gave 12 NMODES after analysing its showing 114 modes created
When i gave 12 NMODES after analysing its showing 114 modes created
please help me with this
Can you share the model file, please?
sir actually i am working in a company i cant share anyway it is 80Mb file commercial vehicle chassis
if you remove the ASET you should get the same number of modes as specified in NMODES.
The extra modes are the number of FEM DOF that are in the interface.
Sir with the help of ASET only i can generate markers in simpack!
OK, If you are using other than CBN and GYUAN, the number of modes without ASET is equal to what you get.
I think the same applies to CBN also.
ok sir
Hello,
I need help!
I am working in optistruct and have used CBN method to make flexbody. I need to use the file in SIMPACK for MBS. Can anyone tell me, how to generate fbi format in hypermesh.
Thanks in advance
