Learning Forum

[CW62]

I wish to conduct an analysis that consists of a static analysis with multiple load steps that result in deformation of the structure, followed by a transient analysis step of the deformed structure. I am attempting to conduct the analysis in ANSYS Mechanical APDL; however, I am unclear on how to conduct the transient analysis following on from the final load step of the static analysis. When I specify ANTYPE,TRANSIENT in the step after the final static analysis load step an error appears saying that the analysis type cannot be changed.

Any help and guidance as to how to carry out such an analysis in ANSYS Mechanical APDL would be very much appreciated. Thank you for your time.

[Erik Kostson]

HI

You should use transient for all analysis (as you saw one can not switch), and in the first say one or two steps do not have a time integration (TIMINT command), which basically results in a static solution. AFter that in the last step you can turn them on and add dynamic loads as needed.

Below is an example of what I meant:
/SOLU
ANTYPE,TRANS
TRNOPT,FULL
TIMINT,OFF,ALL ! static solution no mass matrix and dynamic effects
TIME,1
DELTIM,0.1,0.1,0.1
SOLVE
ANTYPE,TRANS ! second step with integration and dynamic effects on so transient dynamic solution
TRNOPT,FULL
TIMINT,ON,ALL ! dynamic solution on
...
....
TIME,2
DELTIM,0.1,0.1,0.1
OUTRES,ALL,ALL
SOLVE
ANTYPE,TRANS
TRNOPT,FULL
TIMINT,ON,ALL ! dynamic solution on / transient effects
D,1,ALL,0
....
....
DELTIM,0.002,0.002,0.002
OUTRES,ALL,ALL
SOLVE

[CW62]

Thank you for your response, I am very grateful for you help. Deactivating transient effects for the load steps that need to be static works effectively for the simulations I am currently running; however, in the near future I will be developing and running simulations that again require multiple static analysis load steps followed by a transient analysis step, but with piezoelectric and CIRCU94 elements defined within the model. I understand that CIRCU94 elements are only applicable to full harmonic and transient analyses and cannot be used in a static analysis or in a transient analysis with time integration effects turned off.
Bearing in mind the restrictions for CIRCU94 elements, do you have any suggestions as to how I can perform the static analysis on the structure first and then perform a transient analysis on the deformed structure without using the TIMINT command? I will also be using ANSYS Mechanical APDL for the coupled structural-piezoelectric-circuit simulations. Thank you.