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

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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



2 Replies Last Post 2018年1月15日 GMT-0500下午7:28
Edgar J. Kaiser Certified Consultant

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Posted: 3 months ago 2018年1月13日 GMT-0500上午6:18
Updated: 3 months ago 2018年1月13日 GMT-0500上午6:23

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

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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

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Posted: 3 months ago 2018年1月15日 GMT-0500下午7:28

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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