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How to extract Instantaneous Velocity and RMS velocity from a LES solution?

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Old   May 5, 2017, 03:37
Default How to extract Instantaneous Velocity and RMS velocity from a LES solution?
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I have already run a LES simulation (Fluent) of 2D flow over a Dune and now I want to get urms and vrms. How I can calculate this?
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Old   May 6, 2017, 17:35
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Check the box to enable data sampling for time statistics. Unfortunately you have to run it again.
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Old   May 7, 2017, 02:33
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Thank you for your advice. I have switched on time statistics and run the simulation again. Now many new data for export have appeared but still I am not getting any option for RMS velocity. I am attaching the new Quantities that appeared for exporting after I switched on time statistics.
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Old   May 7, 2017, 15:32
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RMSE X velocity and so on are your RMS's of the velocity fluctuations.

It's a common mistake because when people say RMS velocities then actually mean rms of the fluctuations.

Unless you actually want the RMS... then you just add the mean to the RMSE. Btw old versions of Fluent had the RMSE variables incorrectly labeled as RMS. I think newer versions will give you both RMS and RMSE.
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