Hello,
I am trying hard to find some information about the "missing modes" phenomena resulting from the use of specific preconditionning on stiffness matrices (FEM method).
Basically, I am simplifying my stiffness matrix and this leads to missing modes in the new spectrum.
Would you know any...
Hello,
I tried RSYS,1 and DSYS,1 none of them seems to give waht I am looking for ... I know this is possible to do with Ansys because I did it already with another structure that was imported from Nastran.
In order to knoe where could the problem be from I edited the .db files of the...
Hello,
I am using Ansys to study a cyclic symmetric structure. But I just use it to obtain the mass and stiffness matrices of an elementary sector.
In order to make the analyze of the matrices easier, I need to obtain them in global cylindrical coordinates. It is why I have a problem.
After...
Hello,
I would like to use DMAP language to invert very large sparse matrices.
Would anyone have any recommandation regarding this subject ?
Thank you.
Alain
Hello,
I am working with big finite element matrices (64000 x 64000) using sparse function with Matlab.
However, in order to inverse one of these matrices, Matlab and sparse are not efficient anymore.
I heard that Nastran can be used to do it ...
Would anyone know something about it ...
Hello,
I have the answer to your problem ... I had the same one and here is the solution:
'Error in start up script'
'can't find package Itcl while executing
"package require Itcl"
(file "c:\documents and settings\user\program files\ansys inc\v##\commonfiles\launcher\launchermain.itcl"...
Hello,
I am working on contact analysis with large structures. I would like to know if anyone knows something about the algorithms linking Component Mode Synthesis methods and contact algorithms ...
Thank you.
Alain
Hello,
I am looking for documents or any help linked with the study of contact algorithms for reduced structures with component mode synthesis (Craig-Bampton or Craig-Chang-Martinez).
Could you please tell me if you know anything about it ?
Thank you.
Alain
Hello,
I am working on component mode synthesis for the study of plane engines.
I am looking for the mathematical theory behind methods such as the Craig-Bampton method or the Craig-Martinez method. I know the way these methods are working but I am more interested in the studies of new modes...
The problem is that I am working with a structure with these two kind of elements. I know how to extract mass and stiffness matrices from an .inp file with Abaqus but if it doesn't work with these elements so I think these elements are incompatible with the Abaqus keywords "Element Matrix...
Hi all,
I am just wondering if someone is working with element C3D15 or C3D20R, could these elements create some problem for extracting stiffness and mass matrices ?
Thank you.
Alain
Hello,
i am working with Abaqus and I am trying to obtain the mass and stiffness matrices of my structure. I know the command to use in the .inp file but I have problems using the "ELSET" keyword ... Could someone help me ?
Thanks a lot ;)
Alain
