An issue about average wind speed calculation

[xxh0523]

Merry Christmas and Have a Good Holiday!

First of all, thank you for sharing SOWFA. It helps us a lot and we really appreciate it.

Recently, we have been using SOWFA to calculate average wind speed within a wind farm.
We found a possible bug since the computed average wind speed is much smaller than the instant one, which drew our attention.

After checking the source code in /applications/solvers/incompressible/windEnergy/windPlantSolver.ALM/computeAverageFields.H, we made modification as follows and obtained a result that seems reasonable.

Line 15:
Change
UAvg = (UAvg * avgTimeSum) + (runTime.deltaT().value() * U);
to
UAvg = (UAvg * (avgTimeSum - runTime.startTime().value())) + (runTime.deltaT().value() * U);
Line 27:
Change
UAvg = UAvg / avgTimeSum;
to
UAvg = UAvg / (avgTimeSum - runTime.startTime().value());

We hope to make sure whether it is really a bug, or it is just that we are not using your software in the right way.
Looking forward to hearing from you.

Sincerely,
Tannan

[ZY2xlllz]

Hello, I also find that the average speed of my calculation is very small. Do you know the reason? Is it a bug? Looking forward to your reply. Thank you very much.

[xxh0523]

Hello, I also find that the average speed of my calculation is very small. Do you know the reason? Is it a bug? Looking forward to your reply. Thank you very much.

Hi. We think it might be a bug. So we modified the source code as we mentioned in the issue. You could try it and see if the results become reasonable.

[ZY2xlllz]

Thank you very much for your reply. I will try using your code. Wish you success in your research

[xxh0523]

Thank you very much for your reply. I will try using your code. Wish you success in your research

You too.