[NX 8.5] Coupled thermo mechanical analysis 1

[Emiliano87]

Hi, I'm working in NX 8.5 and going crazy trying to make a coupled thermo-mechanical analysis. In the documentation (I believe it is in the advanced nonlinear modeling guide) It says the solver has the option to use TMC that is thermal coupling, and has several options. But I dont seem to find documentation or example on how to implement it. Any of you know how to do it or even if it is possible with NX 8.5? Please help me.

 

[BlasMolero]

Dear Emiliano,
Thermal Stress with NX AdvSim is very easy, the workflow is the following:

A thermal stress analysis can optionally use thermal results as pre-load input for a structural analysis.
To use the pre-load attributes for NX Nastran:
1.- First solve the NX NASTRAN Heat Transfer Analysis (SOL153) and plot temperature results in your model.
2.- Create the new study of Linear Static analysis (SOL101).
3.- In the Simulation Navigator, right-click the subcase in the structural solution and choose Edit.
4.- For Pre-Load Type, choose NASTRAN Temperatures.
5.- Browse and select the NX Nastran *.op2 file solved previously, which contains the temperature results.
(For results from NX TMG/Thermal, set the Pre-Load Type to NX THERMAL Temperatures).

UNDERSTANDING A PRELOAD
When you specify a pre-load, the solver:

• Reads the nodal temperature data from the selected output file (*.op2).
• Applies the temperatures to the nodes of the structure. The meshes must be identical for NX Nastran, but are not required for NX TMG/Thermal that makes an interpolation.
• Uses the strain free temperature from the material data or the solution attributes for the "Δt" calculation.
• Uses the structural material properties, together with any existing structural loads.

Good luck and ... best regards,
Blas.


~~~~~~~~~~~~~~~~~~~~~~
Blas Molero Hidalgo
Ingeniero Industrial
Director

IBERISA
48011 BILBAO (SPAIN)
WEB:

http://www.iberisa.com

Blog de FEMAP & NX Nastran:

http://iberisa.wordpress.com/

 

[Emiliano87]

Hi Blas thank you for your quick answer. I already did the thing you told me here without a problem but my question was if it was possible to do a coupled iterative coupling as its described in NX Nastran 8 Advanced Nonlinear Theory and Modeling guide (page 355 to 360)

"! In iterative coupling, the thermal solution can affect the
structural solution and the structural solution can affect the thermal
solution.
! The coupling from structural to thermal models includes the
following effects:
< Internal heat generation due to plastic deformations of the
material
< Heat transfer between contacting bodies
< Surface
"

Is it possible or I have to learn to modify the .dat to set it manually???

 

[BlasMolero]

Dear Emiliano,
Then I don't understand very well the question: real multiphysic coupled thermo-mechanical analysis is supported only by Advanced Nonlinear Module (SOL601), if you have license for this module then you can run this double-way. If not, if only have license of NX NASTRAN BASIC, then you must use the one-way thermal-to-structural pre-load effect importing temperatures results from heat transfer analysis as thermal loads in the structural model.

For you to know, a new NX Nastran solution sequence, SOL 401 - NLSTEP, has been created. SOL 401 is a multistep, structural solution which supports a combination of static (linear or nonlinear) subcases and modal (real eigenvalue) subcases.

SOL 401 is the structural solution used by the NX multi-physics environment. This environment is a new capability with the NX 9 Advanced Simulation product release. NX 9 supports the one way coupling in which you can apply the resulting temperatures from an NX TMG/Thermal solution to a consecutive SOL 401 structural solution. In future NX releases, all combinations of structural-to-thermal and thermal-to-structural coupling are planned.

This release of SOL 401 lays the groundwork for future nonlinear solution capabilities. Over several releases, it will become a full purpose nonlinear solution supported with the NX multiphysics environment, and also as a stand alone NX Nastran solution.

Best regards,
Blas.

~~~~~~~~~~~~~~~~~~~~~~
Blas Molero Hidalgo
Ingeniero Industrial
Director

IBERISA
48011 BILBAO (SPAIN)
WEB:

http://www.iberisa.com

Blog de FEMAP & NX Nastran:

http://iberisa.wordpress.com/

 

[Emiliano87]

I have advanced nonlinear solution 601 in the solver options but Im going crazy trying to find out what to do to do the real multi-physics coupling. I'm able to do nonlinear plasticity problems but dont see anywhere how can I include thermal solution or restrictions or anything. Is it done in NX advanced solution or does it have to be done manually? Do you know some bibliography that have some example so I can ask the siemens people for it??? Sorry for my bad english

 

[BlasMolero]

Dear Emiliano,
I suggest to contact your VAR or local NX RESELLER to ask for help, ask them to take a look in detail to your NX AdvSim model. Advanced Nonlinear Analysis is a complex task, any problem related with Advanced nonlinear analysis requires to invest such an important time, then I am not your man, sorry ...
Best regards,
Blas.

~~~~~~~~~~~~~~~~~~~~~~
Blas Molero Hidalgo
Ingeniero Industrial
Director

IBERISA
48011 BILBAO (SPAIN)
WEB:

http://www.iberisa.com

Blog de FEMAP & NX Nastran:

http://iberisa.wordpress.com/