Altair RISE

A program to recognize and reward our most engaged community members

Nominate Yourself Now!

Direct Transient Fatigue Analysis

Rodrigo Padilla_21991

Hello, I´m experimenting with optistruct and I am trying to do a direct transient analysis combined with a fatigue analysis but I am struggling with the setup, since the loading comes from a .csv file I made with a sinusoidal shape and magnitude and just place a force of magnitude 1 acting on a component. the direct transient analysis setup is correct and runs, but there's an error with my fatigue setup, does someone know how to set up a fatigue analysis from a direct transient analysis? or have some documentation?

Thanks!

Find more posts tagged with

English

OptiStruct

Accepted answers

All comments

Rahul Rajan_21763

Please look at attached model.Note that FATLOAD for transient won’t reference TABFAT because the time history is directly available from the analysis.

Unable to find an attachment - read this blog

Rodrigo Padilla_21991

Many thanks for your help Rahul!

truongak97

Many thanks for your help Rahul!

Hi RodrigoPadilla
I'm having the same problem.
Did your fatigue analysis work? Could you please share you fem file?

Jaseguras

Hello Rahul,

I have a question regarding to Simulation of Direct Transient Fatigue Analysis. I already ran a Simulation using NLSTA (quasi-static) and used that loadcase to predict damage in Fatigue.

Now I am trying to do the same but using a Non-linear transient instead of quasi-static. However, I got the next error:

GateRel in FATPARM is too large

It doesn't matter how much I decrease the value of GateRel in FATPARM, I always got the same error.

It's important to highlight that the Non-linear transient response run without any problem.