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February 16, 2010, 20:30 
How to monitor a property at a certain set of coordinates??

#1 
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Behrang Asgharian
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Guys!
During an unsteady iteration, how can I get the property (T,P,...) at certain x,y and draw a plot of it versus time? I have used MonitorsSurface in Solve menu but that gives me the integral of a property over an area. Thanks 

February 17, 2010, 01:00 

#2 
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Maxime Perelli
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create points (surface/points), and then solve/monitor (choose vertex average)
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February 17, 2010, 02:10 

#3 
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Behrang Asgharian
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Thanks
I'll give it a try. 

February 17, 2010, 23:28 

#4 
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Behrang Asgharian
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Thanks a million. It worked!!
Can I ask you another question? How can I have a variable initial condition like a sinusoidal pressure throughout the domain I mean for example p=p(x)? How can we have variable body force throughout the domain? Last edited by behrang2009; February 17, 2010 at 23:44. 

February 18, 2010, 01:06 

#5 
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Maxime Perelli
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if you mean a BC with a sinusoidal signal, you can use a profile or UDF
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February 18, 2010, 01:52 

#6 
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Behrang Asgharian
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I mean how I can put the pressure sinusoidally on the cells throughout the domain. Take a narrow tube for example that pressure changes along x axis but constant at every cross section. I want to use this as an initial condition and let the flow oscillate.
I have used UDF in a different way (DEFINE_PROFILE) and kind of got what I wanted. I wonder if we can impose such an initial condition on the cells or not. DEFINE_PROFILE is used for faces. Is there any Macro that we can use for the domain? Thanks 

February 18, 2010, 02:01 

#7 
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Maxime Perelli
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no idea, sorry.
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In memory of my friend Hervé: CFD engineer & freerider 

March 2, 2010, 21:48 

#8 
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Behrang Asgharian
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Hi Again!
Since you helped last time, I think you know the answer to the following question of mine: I am modeling oscillating flow which is naturally unsteady. I need to integrate some field functions over one period T. In what menu can I such an option? Thanks Good luck Behrang 

March 3, 2010, 00:59 

#9 
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Maxime Perelli
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I never did that, but if you check the help, something may help you.
******** 25.17.4 Postprocessing for TimeDependent Problems: The postprocessing of timedependent data is similar to that for steadystate data, with all graphical and alphanumeric commands available. You can read a data file that was saved at any point in the calculation (by you or with the autosave option) to restore the data at any of the time levels that were saved. FLUENT will label any subsequent graphical or alphanumeric output with the time value of the current data set. If you save data from the force or surface monitors to files (see step 5 in Section 25.17.1), you can read these files back in and plot them to see a time history of the monitored quantity ... If you enabled the Data Sampling for Time Statistics option in the Iterate panel, FLUENT will compute the time average (mean) of the instantaneous values and rootmeansquares of the fluctuating values sampled during the calculation. The mean and rootmeansquare (RMS) values for all solution variables will be available in the Unsteady Statistics... category of the variable selection dropdown list that appears in postprocessing panels. You can set the Sampling Interval such that Data Sampling for Time Statistics can be performed at the specified frequency
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In memory of my friend Hervé: CFD engineer & freerider 

March 3, 2010, 18:04 

#10 
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Behrang Asgharian
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Thanks
You mean FFT in the plot menu? 

March 4, 2010, 01:29 

#11 
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Maxime Perelli
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I don't believe it is FFT (I don't have Fluent anymore, so I can't check)
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In memory of my friend Hervé: CFD engineer & freerider 

March 4, 2010, 01:49 

#12 
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Behrang Asgharian
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thanks anyway


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