Learning Forum

[Ilaria]

Dear all,

I am performing a nonlinear buckling analysis in Ansys Workbench (2023 R1).

I did the linear buckling analysis and I need to simultaneously add the 10 mode shapes obtained from the Eigenvalue Buckling System as geometric imperfections into a new Static Structural System.

I could not find a solution for the current version of Ansys. Is there a way?

Thanks in advance

[Lydia Lymperopoulou]

Hi Ilaria,

Your workflow should be as follows:

You basically need to export the results with apdl script and use upgeom to enforce the new displacements. Export the cdb file and import the cdb file back to mechanical using External model.

A command snippet should be added in B6 and use these commands:

https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v232/en/ans_cmd/Hlp_C_UPGEOM.html?q=upgeom

https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v232/en/ans_cmd/Hlp_C_CDWRITE.html?q=cdwrite

https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v232/en/ans_cmd/Hlp_C_COPY.html?q=%2Fcopy

 

 

[Erik Kostson]

To add, the below post should be of help.

/forum/forums/topic/multiple-mode-geometric-imperfection/

All the best

Erik

[Ilaria]

Thank you for your replies.

 

I followed your suggestions and wrote the following apdl script:

 

/prep7

UPGEOM,5e-6,1,1, file, rst, 

UPGEOM,5e-6,1,2, file, rst,

UPGEOM,5e-6,1,3, file, rst,

UPGEOM,5e-6,1,4, file, rst,

UPGEOM,5e-6,1,5, file, rst,

UPGEOM,5e-6,1,6, file, rst,

UPGEOM,5e-6,1,7, file, rst,

UPGEOM,5e-6,1,8, file, rst,

UPGEOM,5e-6,1,9, file, rst,

UPGEOM,5e-6,1,10, file, rst,

cdwrite,db,file,cdb

/copy,file,cdb,,..\..\bucklingmodes,cdb

 

It seems to work to me but, if it is possible, I would appreciate your feedback.

 

Thank you again