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Ramping Courant Number

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Old   April 22, 2011, 12:49
Default Ramping Courant Number
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Martin
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A quick query about the 'ramping' of values in StarCCM+.
As I am running a highly hypersonic case the starting Courant number had to be small, but I have put a rampping function in to gradually increase the value over a number of iterations.
The set up in Star is straight forwards with a start and end iteration, and a initial Courant number defined. But what I could not gather from the UG was a what value does the Courant number reach or plateau out at, or is this just dependednt on the solution and applies the maximum value it can?

Cheers,
Martin
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Old   April 22, 2011, 13:59
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See attached image ...
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File Type: jpg final_CFL.jpg (77.6 KB, 96 views)
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Old   April 23, 2011, 08:06
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Cheers! I did wonder about that.
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Old   April 25, 2011, 11:06
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Ryne Whitehill
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Originally Posted by screech1987 View Post
Cheers! I did wonder about that.
It is a bit cryptic, the way they have the final number seperated from the initial number.
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Old   April 28, 2011, 17:38
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Not necessarily cryptic. The ramp just has its own definition.
Imagine, you want to change the CFL number much after the end of the ramp. Why should you search for the CFL number by looking in the ramp? There's no reason and some guy might complain about a cryptic way they have hidden the CFL number in the ramp node.

So to keep it seperate from the ramp (and its initial value) is just as much cryptic as it might be in another case when you have put it together.
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Old   April 29, 2011, 09:54
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Originally Posted by abdul099 View Post
Not necessarily cryptic. The ramp just has its own definition.
Imagine, you want to change the CFL number much after the end of the ramp. Why should you search for the CFL number by looking in the ramp? There's no reason and some guy might complain about a cryptic way they have hidden the CFL number in the ramp node.

So to keep it seperate from the ramp (and its initial value) is just as much cryptic as it might be in another case when you have put it together.
I understand why they have it how they do, but still think it is a bit cryptic not to have the start value and end value next to eachother. Maybe the placement of the variable should be moved when ramp is turned on?
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Old   May 1, 2011, 06:22
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That would be an option, but that would affect the Java API as well, so most likely that will not be changed.
An to be honest, it's no big issue as long as you know where you can find it, isn't it?
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Old   May 2, 2011, 08:18
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Originally Posted by abdul099 View Post
That would be an option, but that would affect the Java API as well, so most likely that will not be changed.
An to be honest, it's no big issue as long as you know where you can find it, isn't it?

It is not an issue to me, but I think it does confuse people new to the software (which is why we have a thread here)
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