About Umean

kkpal · June 25, 2013, 05:52

dear all,
I put fieldaverage function into controlDict, and I run the simulation for, say 100s, then I stop here. Since at the beginning of the simulation non-physical phenomenon might occur, this would make the average filed, like UMean and pMean inaccurate.
To eliminate the effect from non physical phenomenon, I resume the simulation at t=100s. From then on, are UMean and pMean calculated from t=100? or are the values before t=100s still be counted into the average field?

cfdonline2mohsen · June 25, 2013, 14:52

Dear Kai,
Usually the averaging must be done after the full convergence i.e. in your case you must turn on averaging after t=100sec (Not from t=0sec) then continue your run for another 100sec i.e. you should sample your data at t=200sec.

June 25, 2013, 05:52	About Umean	#1
kkpal Senior Member Join Date: Jan 2013 Posts: 135 Rep Power: 13	dear all, I put fieldaverage function into controlDict, and I run the simulation for, say 100s, then I stop here. Since at the beginning of the simulation non-physical phenomenon might occur, this would make the average filed, like UMean and pMean inaccurate. To eliminate the effect from non physical phenomenon, I resume the simulation at t=100s. From then on, are UMean and pMean calculated from t=100? or are the values before t=100s still be counted into the average field? ScarFace likes this. Last edited by kkpal; June 25, 2013 at 09:10.

June 25, 2013, 14:52		#2
cfdonline2mohsen Senior Member Mohsen KiaMansouri Join Date: Jan 2010 Location: CFD Lab Posts: 118 Rep Power: 16	Dear Kai, Usually the averaging must be done after the full convergence i.e. in your case you must turn on averaging after t=100sec (Not from t=0sec) then continue your run for another 100sec i.e. you should sample your data at t=200sec. kkpal, openfoammaofnepo and ScarFace like this. __________________ “If you have an apple and I have an apple and we exchange these apples then you and I will still each have one apple. But if you have an idea and I have an idea and we exchange these ideas, then each of us will have two ideas.”

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