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How to redo last time step?

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Old   February 15, 2019, 09:46
Question How to redo last time step?
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Since we control the time step size ourselves, we need to
  1. get the former state, i.e. last time state,
  2. reset the time step size
before we continue in the time loop.

What is the current and most efficient way to do that? What is the difference between storeOldTime and storePrevIter?
What happens implicitly in Time class? What has to be enforced explicitly?
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Old   February 15, 2019, 10:50
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Quote:
Originally Posted by Pfiffikus View Post
Since we control the time step size ourselves, we need to
  1. get the former state, i.e. last time state,
  2. reset the time step size
before we continue in the time loop.

What is the current and most efficient way to do that? What is the difference between storeOldTime and storePrevIter?
What happens implicitly in Time class? What has to be enforced explicitly?
In theory you output files when you run and those states for each variable store whatever the last time step accomplished so basically my idea is to set the controlDict to the last time step and run it from there. Either that or I misunderstood your question completely.
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Old   February 20, 2019, 07:46
Exclamation for clarification
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Quote:
Originally Posted by massive_turbulence View Post
... to set the controlDict to the last time step and run it from there.
Since my question is located in the sub-forum Programming & Development we don't want to interrupt the simulation, but modify the time-stepping on the fly.

We are somehow confused by the referenced, but contradicting(?) posts ...
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Old   February 20, 2019, 08:36
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Quote:
Originally Posted by Pfiffikus View Post
Since my question is located in the sub-forum Programming & Development we don't want to interrupt the simulation, but modify the time-stepping on the fly.

We are somehow confused by the referenced, but contradicting(?) posts ...
The controlDict file is referenced initially and the variable for the time-step must be stored somewhere. Is that the variable you're asking about?

Nevermind, haven't had my coffee yet, went to the links you provided. Seems like someone already tried that method.

Last edited by massive_turbulence; February 20, 2019 at 09:45.
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Old   February 21, 2019, 03:43
Question more explanation/documentation necessary
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Quote:
Originally Posted by massive_turbulence View Post
Is that the variable you're asking about?
Yes, on the one hand, but on the other hand we like to understand the mechanism of storing old states.
Our main focus is to undo last time step, i.e. set all values to recent state.
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