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Explicit CEL variables

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Old   November 16, 2022, 08:25
Question Explicit CEL variables
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Juan Luis
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Hi everybody,

Anyone knows how can you use explicit variables in CEL? Or, is it possible to access variables or properties of previous time steps?

Thank you.
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Old   November 16, 2022, 16:28
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Glenn Horrocks
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What do you mean by explicit variables? Example = 10[m/s]+2*Velocity is an explicit variable.

Can you access variables from previous time steps? This is not supported, but there is a unsupported method of doing it: see
Update Loop = TRANS_LOOP
Why the Trans_Loop trick does not work? No old time value obtained!

Note it is pretty unreliable and does not work in every case (that is why it is unsupported)

Alternately you can write some user fortran to do it.
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Old   November 16, 2022, 16:38
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adding to Glenn's question:

what are you trying to achieve that needs variables at previous timesteps?
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Old   November 17, 2022, 09:17
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I have a CEL expression that have to be evaluated with variables at the previous step. An example of this could be a temperature ON/OFF control.
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Old   November 17, 2022, 17:15
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Glenn Horrocks
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It would be good if you described what you are actually trying to do because there usually is a better way of doing it.

But to answer your question: You cannot do temperature on/off control in a steady state simulation as it will never converge. If you want to do it in a transient simulation you can try the TRANS_LOOP approach or a user fortran routine, as previously suggested.
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