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Thermal Expansion 2D don't agree with analitical value of 3D

Posted 12.01.2018, 20:59 GMT-5 Structural & Acoustics, Results & Visualization, Structural Mechanics Version 5.3a 2 Replies

Gabriel Gama
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Hi,

I've been using the 2D Thermal Expansion Module to verify some results. I've built a copper bar with 300 x 10x3.5 (The 3.5was put on thikness of solid mechanic module). It shows that the displacement was 5.2 when subjected to an enhance of 800K. The theoric value gives . This is a diference abaut 30%, even thoug it is a very simply simulation. But if I simulate the same values for a 3D sistem, the result agree with theory. Why is there this difference? Is it possible that I've been using the of displacement measurement wrongly?

Thanks and best regards

Gabriel Gama

https://drive.google.com/open?id=1fpRo2YUGzLP_6pEzkgatqxFobOLdtT3- https://drive.google.com/open?id=1eAWI9lId5ZE1Am88VwszdIX9NqewXKYH

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2 Replies Last Post 15.01.2018, 19:28 GMT-5
Edgar J. Kaiser Certified Consultant
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Posted: 7 years ago 13.01.2018, 06:18 GMT-5
Updated: 7 years ago 13.01.2018, 06:23 GMT-5

Gabriel,

this is a thin plate, so you should use the plane stress approximation instead of plain strain in the solid node. The predescribed displacement is not required and imposes a deviation from the analytic solution.

Cheers Edgar

-------------------
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
Gabriel, this is a thin plate, so you should use the plane stress approximation instead of plain strain in the solid node. The predescribed displacement is not required and imposes a deviation from the analytic solution. Cheers Edgar
Gabriel Gama
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Posted: 7 years ago 15.01.2018, 19:28 GMT-5

Dear, E. J. Kaiser.

I'd like to thank you. I made like you said and worked.

Best regards,

Dear, E. J. Kaiser. I'd like to thank you. I made like you said and worked. Best regards,

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