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Change the YOUNG’s modulus

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I'm running this coupled heat transfer-structural model .The analysis is time dependent. In my model ,as the temperature rising, the metal has deformed (such as swelled).But in reality,the metal could be melting , so the elements could not taked into account(death elements) .So when the temperature is reaching the melting point, I want to apply a very low YOUNG’s modulus E as a subdomain setting.For the exemplary process flow a YOUNG’s modulus of 10exp(12) Pa was used.This low YOUNG’s modulus ensures that death elements do not influence the bending stiffness of the underneath .But I don't know how to change the YOUNG’s modulus.

Could someone can help me solve this problem?In short,when temperature reaching the melting point, apply a very low YOUNG’s modulus E as a subdomain setting.

3 Replies Last Post 2015年9月10日 GMT-4 11:09

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Posted: 1 decade ago 2013年8月27日 GMT-4 11:13
Hello,

you should define your Young's modulus as a function of temperature. To do this you have two alternatives:

1. If you have available a series of point Em-T: go in Definition>Function>Interpolation, then you import your values (t is your x, in your case temperatures; f(t) of course the values of Young's mod). You can then correct the values in order to take into account the "softening" due to melting. Take into account you can also insert parameters in the table (if you want to carry out parametric studies e.g.)

2. Define an analytic function: if you know the function of your material i.e. Em=Em(T), you can insert it in the Material node, or you can define Definition>Function>Analytic. Just as example, if the Young's modulus of the material you are using is linear Em = 10e7*T [GPa], and supposing a melting temperature Tmelt and a value of (reduced) Young's modulus of 10e5 [GPa], you may define: (T<Tmelt)*(10e7*T)+(T>=Tmelt)*(10e5).

Kind regards
Hello, you should define your Young's modulus as a function of temperature. To do this you have two alternatives: 1. If you have available a series of point Em-T: go in Definition>Function>Interpolation, then you import your values (t is your x, in your case temperatures; f(t) of course the values of Young's mod). You can then correct the values in order to take into account the "softening" due to melting. Take into account you can also insert parameters in the table (if you want to carry out parametric studies e.g.) 2. Define an analytic function: if you know the function of your material i.e. Em=Em(T), you can insert it in the Material node, or you can define Definition>Function>Analytic. Just as example, if the Young's modulus of the material you are using is linear Em = 10e7*T [GPa], and supposing a melting temperature Tmelt and a value of (reduced) Young's modulus of 10e5 [GPa], you may define: (T=Tmelt)*(10e5). Kind regards

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Posted: 1 decade ago 2013年8月27日 GMT-4 22:29
Thanks for you reply . But I want to know , in my case , temperatures are unknown which must be got from the solutions .So ,how can I define the function of temperature?
Thanks for you reply . But I want to know , in my case , temperatures are unknown which must be got from the solutions .So ,how can I define the function of temperature?

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Posted: 9 years ago 2015年9月10日 GMT-4 11:09
Using T directly is OK!
Using T directly is OK!

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