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Imposed Temperature on a thermobimetal plate

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Hello,

I am trying to impose a temperature load on a thermobimetal disc which should result in a dynamic snapping Motion because of the different thermal Expansion coefficients. I have previously imported a state file that includes the Change in curvature and stress caused by deep drawing. However, after running the Simulation no Change is visible at all. I am assuming that I did something wrong with the control Cards.

Thank you in advance for your help.

Schnappen_HC_0000.rad Schnappen_HC_0001.rad Schnappen_HC.h3d

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Hi,

 

in the model you shared there are no thermal expansion coefficients defined. Activate /THERM_STRESS/MAT (under HEAT_Input) to add thermal expansion property for Radioss material with curves relating thermal linear expansion coefficient as a function of temperature. I have edited the model by inputing some random CTE on one of the components, just to get some results. 

 

The model you shared has no initialized stress state. Otherwise, there should also be Tables entry in the model browser. 

 

Please do not post the same questions in multiple threads so as not to clutter the forum.

_THERM_STRESS_MAT.pdf Schnappen_edit_0000.rad

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Hello,

Thank you for your reply. You are right, the thermal Expansion coefficients and the initialized stress states somehow got lost when i imported the solver deck into HyperCrash. I have now remodeled everything according to your edited file in HyperMesh. It should work, but doesn't.

And sorry for posting multiple times. Impatience is my strongest vice.

Thank you in advance for your help.Schnappen_0000.rad Schnappen.h3dSchnappen_0001.rad Schnappen.hm

 

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Hi,

the shared HM model has some issues:
-the Passive contact had an empty slave group
-the Disc constraint did not block Y DOF resulting in rigid body motion. Solid elements have only translational DOF so no need to block rotational DOF
-check unit consistency: begin card declares unit system kg, m, s- this means units for stress and modulus should be Pa. The disc with 50 m diameter weighing 14g does not make physical sense. 

Image result for consistent units
-the thermal linear expansion coefficient used 0.01 is too high. The usual range for α is from 10E−7 K−1 for hard solids to 10E−3 K−1 for organic liquids.

Schnappen_edit1_0000.rad

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