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Who to define both TEMP(INIT) an TEMP(MATERIAL) in SOL101

Gears Phenom Gears Phenom
Gears Phenom

Hello experts,

 

short question about NX10 SOL101 (STATIC):

 

If I try to define temperature strain effects with specific

- initial temperature (TEMP(INIT)  = -10 °C)

- real temperature distribution at nearly 30 °C (TEMP(LOAD))

 

What's the way to get temperature dependent material behavior for final temperature distribution?

Is the automatic way that NX NASTRAN uses the real temperature values of load case for material behavior?

 

I could define a temperature set for material TEMP(MATERIAL) but I can only use either TEMP(INIT) or TEMP(MATERIAL) so I'm confused about the functionality of TEMP(MATERIAL) and TEMP(INIT).

 

What's the definition temperature for selecting the temperature dependent Young's modulus? - I'm not sure if it's TEMP(LOAD) or TEMP(MATERIAL)?

 

Who can explain it? - Every suggestion is welcome. Best wishes, Michael

 

| Production: NX10; Development: VB, TCL/TK, FORTRAN; Testing: NX11 | engelke engineering art GmbH, Germany
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4 REPLIES

Re: Who to define both TEMP(INIT) an TEMP(MATERIAL) in SOL101

Siemens Phenom Siemens Phenom
Siemens Phenom

TEMP(MATERIAL) is a concept inherited from MSC Nsatran v2001 that really does not make much sense. We have not supported it in new solution sequences (601/701/401/402) for this reason, but it must be maintained in the legacy solution sequences for backward compatibility.

 

Several releases ago, we tried to document how thermal strains are computed for all of the possible input combinations in great detail in the remarks (8 and 9) for the TEMPERATURE case control card:

 

https://docs.plm.automation.siemens.com/tdoc/scnastran/2019_1/help/#uid:index_QRG:id512096:xid110814...

Re: Who to define both TEMP(INIT) an TEMP(MATERIAL) in SOL101

Gears Phenom Gears Phenom
Gears Phenom

Dear Jim, thank you for answering.

I'd found that article  in documentation too, but I didn't realize that there are additional remarks beyond Remark 7. Smiley Wink2019-02-06_151951.png

 

Next remarks explain a lot. 

 

 

2019-02-06_160111.png

 

But what shall I do to get the thermal behavior of material at T.load?

 

If I want to have ALPHA(T.load) and Young's Modulus E(T.Load) in a case with T.Init and T.Load , that's not possible with "native"  definitions because ALPHA (and Young's Modulus E) is calculated at T.Init ==>

 

EPS.THERMAL = ALPHA(T.Init)*(T.Load - T.Init)

 

So to get ALPHA(T.Load) I have to declare a new

T.Init* = T.Load = T.Init + DELTA.T

with DELTA.T = T.Load - T.Init

 

To have the same (Delta.T* = Delta.T ) I have to declare a new T.Load*

T.Load* = T.Init* + Delta.T = T.Load + (T.Load - T.Init) = 2*T.Load - T.Init

 

Then

Delta.T* = T.Load* - T.Init* = (2*T.Load - T.Init) - (T.Init + T.Load - T.Init) = T.Load - T.Init = Delta.T

 

EPS.THERMAL(T.Load*, T.Init*) = ALPHA(T.Init*) * (T.Load* - T.Init*)

EPS.THERMAL(T.Load*, T.Init*) = ALPHA(T.Init + (T-Load - T.Init)) * ((2*T.Load - T.Init) - (T.Init + T.Load - T.Init))

EPS.THERMAL(T.Load*, T.Init*) = ALPHA(T.Load ) * ((T.Load - T.Init) - (T.Init - T.Init))

EPS.THERMAL(T.Load*, T.Init*) = ALPHA(T.Load ) * (T.Load - T.Init)

 

Is it possible to rearrange temperature distributions by adding two spacial (or nodal) distributions, derived in two solver processes (in two OP2)?

 

Or is it easier to manipulate the thermal material behavior for ALPHA and Young's Modulus by means of "Value Shifting": I guess, shifting is only possible if Delta.T is constant for complete structure.

 

Is this the correct way? - With regards, Michael

| Production: NX10; Development: VB, TCL/TK, FORTRAN; Testing: NX11 | engelke engineering art GmbH, Germany
| Kudos for good posts! And if my post answers your question, please mark it as an "Accepted Solution".

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Re: Who to define both TEMP(INIT) an TEMP(MATERIAL) in SOL101

Siemens Phenom Siemens Phenom
Siemens Phenom

Evaluating material properties at a LOAD temperature is beyond the scope of the linear solution sequences.

 

You would have to use one of the nonlinear solution sequences (106, 401, 402, 601 and 701) to do this. See Remark 9

 

Note that if PARAM, LGDISP=-1 and if there are no material nonlinear properties defined (i.e. MATS1), then the solution will essentially be linear, with the material properties evaluated at the load temperature.

Re: Who to define both TEMP(INIT) an TEMP(MATERIAL) in SOL101

Gears Phenom Gears Phenom
Gears Phenom

Al right, then I know how to do. Thank you. Michael

| Production: NX10; Development: VB, TCL/TK, FORTRAN; Testing: NX11 | engelke engineering art GmbH, Germany
| Kudos for good posts! And if my post answers your question, please mark it as an "Accepted Solution".

To the Rescue Great Thinker Well Liked Front Line