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Cooling Rate at equilibrium condition
Posted 2014年12月10日 GMT+1 11:34Heat Transfer & Phase ChangeVersion 4.42 Replies
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Hi everyone,
I'm calculating the solidification of the melting of a plastic when passing through a cooling die with a certain velocity. The prozess is transient and at a certain point it came in an equilibrium condition. The problem is, when I calculate the cooling rate "Tt", it has positive and negative values (must to be only negative), although the temperature profile is descendent (T2
How can I solve this problem?
Thank you in advance!
I'm calculating the solidification of the melting of a plastic when passing through a cooling die with a certain velocity. The prozess is transient and at a certain point it came in an equilibrium condition. The problem is, when I calculate the cooling rate "Tt", it has positive and negative values (must to be only negative), although the temperature profile is descendent (T2
How can I solve this problem?
Thank you in advance!
2 Replies
Last Post 2015年1月13日 GMT+1 11:37
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Posted:
1 decade ago
Dear Nicolas,
I saw that your question remained unanswered for a couple of days.
Your negative time derivatives may occur from
- inconsistent initial and boundary conditions or
- from inappropriate discretization in space (mesh) or time (time dependent solver settings)
Finally, too high absolute tolerance in the time-dependent solver settings could be the reason.
In any case it should be possible to resolve this. If you need help with your model, feel free to
send it through our support center.
Best regards,
Sven
I saw that your question remained unanswered for a couple of days.
Your negative time derivatives may occur from
- inconsistent initial and boundary conditions or
- from inappropriate discretization in space (mesh) or time (time dependent solver settings)
Finally, too high absolute tolerance in the time-dependent solver settings could be the reason.
In any case it should be possible to resolve this. If you need help with your model, feel free to
send it through our support center.
Best regards,
Sven
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Posted:
1 decade ago
Thanks for your answer Sven.