Hello I am tying to apply an input displacement in freq domain in a model.
I am able to apply a real part of a displacement but i am not able to apply the imaginary part.
below how I set the analysis
the previous script work fine if i try to add the IMAG part of the the displacement using for example does not work
*Boundary,AMPLITUDE=A1
Internal_Selection, 1, 1, 1
*Boundary,AMPLITUDE=A1,LOAD CASE=2
Internal_Selection, 1, 1, 1
any idea? or work around?
Is there an error message or just no results ? Can you share the whole file ?
It may not work properly. In Abaqus, you can’t use prescribed displacement BCs in mode-based SSD analyses at all, you have to use *BASE MOTION instead.
Thanks for the replay,
attached by mail the model that I used for make a test.
if you try to add LOAD CASE=2 to boundary i did not get results for step 2.
Instead in calculix it is possible use the *BASE MOTION for providing in freq domain a real and imag excitation?
if yes can you provide to me an example?
if in the model you try to add for example you did not get consistent results:
*BOUNDARY,AMPLITUDE=A1,LOAD CASE=1
Internal_Selection-1_Incasro, 1, 1, 1
*BOUNDARY,AMPLITUDE=A1,LOAD CASE=2
Internal_Selection-1_Incasro, 1, 1, 1
I submitted this in Abaqus (using direct integration type of SSD analysis because only this one allows non-zero BCs). Here are the results you requested:
Apparently, limitations of CalculiX prevent you from getting the results in this case. I’m not sure if it can be even called a bug but maybe yes - after all, there is a LOAD CASE parameter for BCs. Perhaps it just doesn’t work well in combination with other features.
Thanks for your double check, so if i got correctly using Calculix I can’t assign non-zero BCs ( in FREQUENCY DOMAIN ANALYSIS) considering IMAG part but just the real one, Am I correct?
It’s not mentioned in the documentation so would require additional testing with as simple models as possible. It may just not work in certain configurations. There were serious issues with SSD analyses in previous versions of CalculiX. They got fixed but there may still be other problems that we don’t know about.