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How to apply temperature (both)?

In my structural anlysis problem I have to apply different temperature load at each subcase and material properties are temperature dependant. While analysisng each subcase meterial temperature and temperature load should be same. I saw temperature(both) option in help file for this purpose. But I can't find that in NX. How I can use temperature (both) option?.

I am using NX 9.1.

5 REPLIES

Re: How to apply temperature (both)?

NX does not support the TEMP(BOTH) definition.

 

You have a couple of options:

  1. Specify a temperature LOAD in NX. Use the Write, Edit & Solve solution to hand edit the deck and change the exported TEMP(LOAD) to TEMP(BOTH) prior to solving.
  2. Note in the NX Nastran QRG, Remark 8 for TEMPERATURE case control, that the combination of TEMP(LOAD) and TEMP(MATERIAL) results in the same thermal strain equation as TEMP(BOTH), i.e. alpha (calculated at he material temperature) * (Tload - Tref). You can define the same temperature for TEMP(LOAD) and TEMP(MATERIAL) in NX and solve without editing.

Re: How to apply temperature (both)?

 

Hi JimB,

Thanks for your reply.

 

I edited the deck as shown below. I changed TEMP(LOAD) to TEMP(BOTH) for all subcases.

************************************************************

SUBCASE 1
LABEL = Time  0.000
TEMP(BOTH) = 201
$*  NX Step: Time  30.00
SUBCASE 2
LABEL = Time  30.00
LOAD = 5
TEMP(BOTH) = 202
*************************************************************

I am not getting a solution by doing this and the fatal message from the F06 file is given below

*************************************************************

 *** USER FATAL MESSAGE 633 (IFP1D)
     INCONSISTENT USE OF TEMPERATURE CASE CONTROL CARD.
     EITHER A TEMPERATURE(INIT), TEMPERATURE(MATERIAL) OR A TEMPERATURE(BOTH) CASE CONTROL CARD IS ALLOWED PER RUN.

****************************************************************

In each subcase temperature load is different and the software should take the material property curresponding to that load temperature. How I can do that?

Solution
Solution
Accepted by topic author Syamjith
‎08-26-2015 04:32 AM

Re: How to apply temperature (both)?

You are trying to change the material temperature in a linear analysis. This is not allowed. QRG Remark 1:

 

In a linear, non-superelement analysis, only one temperature-dependent material request can be made, and should be specified above the subcase level. A fatal error will occur if multiple temperature-dependent material requests are made. See also Remarks 6 and 7.

In a superelement analysis, each superelement subcase can have a different TEMPERATURE(MATERIAL), but consecutive load cases must have consistent TEMPERATURE(MATERIAL).

 

In a linear analysis, the stiffness is formed only once. In trying to change the material temperature in the second subcase, you are asking for the stiffness to be reformed, which is a nonlinear analysis, not a linear analysis.

 

You need to run non-linear to do what you want to do.

Re: How to apply temperature (both)?

I tried sol 106 and sol 601, but I cant apply different material temperature in each subcase. I tried NX multiphysics also. I dont know whether multiphysics support 2D geometry. Please suggest Solver and Solution type to be used for this purpose. 

Solution
Solution
Accepted by topic author Syamjith
‎08-26-2015 04:32 AM

Re: How to apply temperature (both)?

TEMPERATURE(MATERIAL) is only supported for linear solution sequences and must be specified in the global case. In these solutions, material properties are evaluated at the start of the solution and remain constant throughout.

 

For nonlinear solution sequences, TEMPERATURE(MATERIAL) is not supported and will result in a FATAL error. Temperature dependent material properties are updated based on the TEMPERATURE(LOAD).

 

See Remark 9 under Case Control TEMPERATURE card in the QRG.