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Cooling Rate at equilibrium condition
Posted 10 dic 2014, 05:34 GMT-5 Heat Transfer & Phase Change Version 4.4 2 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<T1, so to say).
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<T1, so to say).
How can I solve this problem?
Thank you in advance!
2 Replies Last Post 13 gen 2015, 05:37 GMT-5
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Posted:
10 years 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:
10 years ago
Thanks for your answer Sven.