[OpenFOAM] Paraview: "Plot selection over time" runs very slow (flow rate calculation)

noboady · March 19, 2015, 06:52

Hi,
I am calculating the flow-rate through an open channel by:
1) Clip alpha at 0,5
2) Slice the wanted location
3) Calculate the magnitude of velocity - mag(U)
4) Integrating the cell
and this runs fine and very fast.

I want to get the flow rate over time (integrated velocity) and so I am using the "plot selection over time" filter and this works as well, BUT very slow (~10 to 15 min for one calculation). My project has got 200 timesteps and 10 Variables so there are 2000 cells to calculate what i thougth would run very fast. Is there anything i am missing, any thoughts?

best regards
noboady

Jack001 · April 8, 2016, 17:32

I have the same problem. I have filtered my data down to a single extraction point and now I want to save the time series of that point to a file. I have about 450 time steps in a single file and this alone takes a few minutes. I have several of these result files and will also want to extract many points for each taking an annoyingly large amount of time.

Why is this the case? Is there any way to speed up the process!?

March 19, 2015, 06:52	Paraview: "Plot selection over time" runs very slow (flow rate calculation)	#1
noboady New Member Join Date: Mar 2015 Posts: 1 Rep Power: 0	Hi, I am calculating the flow-rate through an open channel by: 1) Clip alpha at 0,5 2) Slice the wanted location 3) Calculate the magnitude of velocity - mag(U) 4) Integrating the cell and this runs fine and very fast. I want to get the flow rate over time (integrated velocity) and so I am using the "plot selection over time" filter and this works as well, BUT very slow (~10 to 15 min for one calculation). My project has got 200 timesteps and 10 Variables so there are 2000 cells to calculate what i thougth would run very fast. Is there anything i am missing, any thoughts? best regards noboady Last edited by noboady; March 19, 2015 at 09:56.

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April 8, 2016, 17:32		#2
Jack001 Member Jack Join Date: May 2015 Posts: 98 Rep Power: 11	I have the same problem. I have filtered my data down to a single extraction point and now I want to save the time series of that point to a file. I have about 450 time steps in a single file and this alone takes a few minutes. I have several of these result files and will also want to extract many points for each taking an annoyingly large amount of time. Why is this the case? Is there any way to speed up the process!?