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Old   September 13, 2010, 11:42
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Hi,
I need to get the weighted average value of a variable in two different zones. How can i split the mesh like zone1 (upper part) and zone2 (lower part) to get these results?

The actual code that im using is:
scalar averageT = T.weightedAverage(mesh.V()).value();

but as you can see it gets the whole mesh values.

Is it possible to specify like mesh.V(zone1) and mesh.V(zone2) ?
If its possible how can i divide the mesh? im using blockMesh with several blocks.

Any other suggestion on how to collect these results?

Thanks,
Guilherme
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Old   September 13, 2010, 13:31
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Laurence R. McGlashan
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You could look at using cellSet and something like boxToCell. I had to do something similar recently to calculate the weighted average of a variable within a certain area of the mesh.

I've attached the files if you're interested.
Attached Files
File Type: gz holdupCalculator.tar.gz (2.3 KB, 6 views)
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Old   September 14, 2010, 05:58
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Hi Laurence!
Thank you for the fast answer and the calculator!
I compiled it and it seems to be working, but my output is like this:

Code:
Create time

Create mesh for time = 0

Time = 0
Reading holdupCalculationDict
Time = 500
Reading holdupCalculationDict
Time = 1000
Reading holdupCalculationDict

ExecutionTime = 9.08 s  ClockTime = 10 s

End
Nothing is generated or changed. Should I do some preparation on my mesh before or just the holdupCalculation file in the /system is enough?

Thanks,
Guilherme
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Old   September 14, 2010, 06:18
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Laurence R. McGlashan
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I've quickly made it more general to average any variable (see attached).

You'll have to change the name of the variable in holdupCalculation and the dimensions of the box you're averaging the variable in. The variable must be in the time folders for anything to be output.

If you want a shape other than a box you'll have to alter the code slightly.
Attached Files
File Type: gz holdupCalculator.tar.gz (2.3 KB, 12 views)
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Old   September 14, 2010, 07:40
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Now it worked perfectly! You did a great job with this code.
Thank you a lot Laurence.

Guilherme
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Old   September 14, 2010, 08:01
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No problem, be careful with it. It's a good idea to work out a rough estimate for the average to make sure it's calculating it correctly.
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