Nastran Thermo-Structural Analisys with iLogic

[Slakaz]

Hello,
I have to make thermo-structural analisys of an object which is heating. I've made transient thermal analisys and got temperature field (with like few thousands steps- yeah, it's a long process) and now have to make structural analisys. As far as I know there is no possibility to define transient static analisys (pressure dependant on time with imported temperature field from consecutive steps) in Nastran (or maybe I couldn't find it so please enlighten me), so I thought I might use iLogic and multiple subcases.
I'm using as help:
http://help.autodesk.com/view/NINCAD/2021/ENU/?guid=GUID-8DAC709F-E247-464F-A625-37E685949F1F
I've encountered some problems though (both of them apply to iLogic):
1. Can you duplicate and edit loads or only define new?
2. How you define load "from output"? I cannot find a way/parameters to input "results file" with temperature field and to choose "output set"(step) and "nodal load"(temp).

Would be very grateful for any help.

[Slakaz]

And one more. Is it possible to use with "ForLoad" numbers to define subcase/load id?
Let's say I'd like to make a loop where consecutive subcases/loads will be defined with iteration number. Atm it doesn't let me type other arguments than strings typed within "ForLoad" (even conversion to strings/outside strings doesn't work).

[Vilas.kumar.jawalkar]

@Slakaz 

Thank you for posting your query in forum.

Can you briefly explain about your analysis - Transient static analysis(pressure dependent on time with imported temperature from consecutive).

For iLogic queries:
1. No, you cannot duplicate or edit loads this is not supported yet. Should define new loads.

2. From output load type is not supported for now, I will get back to you on this after confirming with development team and also will make sure to update the help page on From Output load type.

3. I would request you to post this query in Inventor forum, this seems more related to coding than Nastran.

Thanks
Vilas Jawalkar

[Slakaz]

Thanks for Your response.
As for my analisys. I have to analyze a heating process of a steam valve in power plant. The heating process may take up to few hours, where ,after some period of time, steam parameters and mass flow are changed. So first of I have to make transient thermal analysis to get body temperature during heating period. Then I have to make structural analisys, where loads would be imported body temperature and pressure (which changes over time aswell). And perfect solution, for me, would be to define (somehow) pressure time dependent (like I did with convection in transient thermal). But as far as I know it's not possible (right?). So I have to make xxx subcases where I import single step of a body temperature and define pressure for each subcase. That's why I wanted to automatize it.

[Vilas.kumar.jawalkar]

@Slakaz 

Thank you for your clear explanation,

Yes this is not possible in Nastran right now - the temperatures from a transient heat transfer analysis cannot
be used to perform a transient stress analysis. This looks like an good option to have in Autodesk Inventor Nastran, I would request you to raise the case in Idea Station to add this feature and vote for it. And also there is an suggestion in the Idea station for -"Transfer n conduct the analysis for all substeps in thermal stress analysis" please vote for it.  

Thanks

Vilas Jawalkar