about fatigue analysis

Beta

 i am doing a fatigue analysis using transient (direct). I read in help that the TID should be BLANK if the LCID references transient loadcases. so I left the TID as <Unspecified>, didn't choose or create any TABFAT. When I ran the OptiStruct, there was a error #1000: incorrect data field #3 with the FATLOAD. Could  anyone help me find out what is wrong here. thanks

Altair Forum User

Hi Toan,

 

Can you check if FATLOAD has the transient subcase or any other?

Beta

yes. i created a loadstep name TRANSIENT for transient and all data for the this loadstep. I ran the transient analysis. it worked and gave a true result. Then In  FATLOAD, i choosed the created TRASIENT loadstep for LCID.

tinh

Altair Forum User said:

 i am doing a fatigue analysis using transient (direct). I read in help that the TID should be BLANK if the LCID references transient loadcases. so I left the TID as <Unspecified>, didn't choose or create any TABFAT. When I ran the OptiStruct, there was a error #1000: incorrect data field #3 with the FATLOAD. Could  anyone help me find out what is wrong here. thanks

 

 

Hi,

maybe  <Unspecified>  does not mean 'BLANK', so try opening your *.fem file and replace '0' in field#3 of FATLOAD  by ' '   (space)

Beta

i tried but it didn't work. /emoticons/default_sad.png' srcset='/emoticons/sad@2x.png 2x' title=':(' width='20' />

tinh

Hey Toan

I tell you that change number '0' in field#3 of FATLOAD in your file *.fem,  how did you do that???

I mean you have to open it by a text editor (like nodepad, nodepad++) and replace '0' by a space ' '

because in hypermesh you cannot set it to 'BLANK'

Maybe Altairians will fix optistruct template soon. while waiting them, you can use this template if you have to repeat your work,

I modified them so you can right-click on number '0' below 'TID' to make it 'BLANK'

    (unzip/copy these to hw13.0 folder)

 

and modified *.fem file:

 

Unable to find an attachment - read this blog

Beta

thank you so much.  i really did not know how to change it to Blank. thanks for your instruction.

Altair Forum User

Hi,

 

You can edit the solver file in any text editor.