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Time-averaged velocity plot for a transient simulation

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Old   January 5, 2012, 07:53
Unhappy Time-averaged velocity plot for a transient simulation
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Hi,

I want to plot a time-averaged cross-sectional velocity profile plot.

I can plot the velocity profile for a specific time, but how do can I plot time-averaged velocity profile for a specific range of time interval.

Can any one help me?

Thank you.
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Old   January 5, 2012, 09:36
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Quote:
Originally Posted by mali28 View Post
Hi,

I want to plot a time-averaged cross-sectional velocity profile plot.

I can plot the velocity profile for a specific time, but how do can I plot time-averaged velocity profile for a specific range of time interval.

Can any one help me?

Thank you.
Hi,
I've done it but it's not very easy at least in ver. 6.3.
you can export your data and find the average flow in another software like MATLAB and then prepare it for fluent interpolation or showing in Tecplot.

Bests,
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Old   January 5, 2012, 10:49
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Quote:
Originally Posted by Amir View Post
Hi,
I've done it but it's not very easy at least in ver. 6.3.
you can export your data and find the average flow in another software like MATLAB and then prepare it for fluent interpolation or showing in Tecplot.

Bests,

I have version 12.1
So, I have to export the data for each time step and get an average value in other software like excel? That will be an extremely painstaking when the averaging interval is very large and time step size is very small as in my case.



There must be some easy way of doing it in Fluent 12.1

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Old   January 5, 2012, 11:05
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Old   January 5, 2012, 11:13
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It is available in fluent
How can I do it? I could not find this feature in ver. 12
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Old   January 5, 2012, 11:25
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Quote:
Originally Posted by mali28 View Post
I have version 12.1
So, I have to export the data for each time step and get an average value in other software like excel? That will be an extremely painstaking when the averaging interval is very large and time step size is very small as in my case.



There must be some easy way of doing it in Fluent 12.1

I've done it by automation in both FLUENT and post processor. so it's not very complicated or time consuming.

Bests,
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Old   January 5, 2012, 11:45
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I want to add another way if you haven't run your case yet.
you can also store your desired variables in temporary memory e.g. UDM and then find your average flow without using extra softwares (but I didn't use this procedure before). My previous suggestion is more proper for the cases with saved data in previous simulations.

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Old   April 25, 2012, 07:13
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Quote:
Originally Posted by Amir View Post
I want to add another way if you haven't run your case yet.
you can also store your desired variables in temporary memory e.g. UDM and then find your average flow without using extra softwares (but I didn't use this procedure before). My previous suggestion is more proper for the cases with saved data in previous simulations.

Bests,
Thanks Amir, I found a UDF for computing the time average velocity profiles.

http://cape-forum.com/index.php/topic,1074.0.html
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Old   September 4, 2013, 11:35
Default Average velocity at all point along the pipe/ Calculate mass flow rate along pipe
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Hi,

Is it possible in fluent 14.0 to calculate average velocity after certain time step ( say after every 50 time step) at all point along the pipe, so that I can calculate mass flow rate along the pipe after certain time ?

If anyone has done this type of work or has any idea, please let me know. That will be great help.

Thanks in advance.

Tanjina
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Old   September 4, 2013, 11:51
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First of all, I would like to mention that there is a "data sampling for time statistics" in fluent.
Find the checkbox in the "run calculation" tab.

I actually dont know if the start of the sampling process can be delayed automatically. But what you can do is run your simulation to the point where you want to start the data sampling and activate the data sampling manually at this point.
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Old   September 4, 2013, 12:42
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Originally Posted by flotus1 View Post
First of all, I would like to mention that there is a "data sampling for time statistics" in fluent.
Find the checkbox in the "run calculation" tab.

I actually dont know if the start of the sampling process can be delayed automatically. But what you can do is run your simulation to the point where you want to start the data sampling and activate the data sampling manually at this point.

Thank you Flotus. I am sorry, I couldn't get your message. By data sampling, is it possible to calculate average velocity at every node along the 2D pipe? I need it badly. Would you please explain a bit more ?
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Old   September 4, 2013, 12:52
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When data sampling is enabled, you get the time-averaged variables for the whole flow field (and some more quantities, refer to the manual for details) as a result of the simulation.
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Old   September 4, 2013, 21:16
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Originally Posted by flotus1 View Post
When data sampling is enabled, you get the time-averaged variables for the whole flow field (and some more quantities, refer to the manual for details) as a result of the simulation.

Thank you Flotus. I have read the article on user manual. I have one question. How can I custom field function ?

And another question is, in fact I need area averaged velocity after certain time step.( i.e. every 50 step). Is it possible by Data sampling for time statistics option ? Sorry, I tried to understand from manual, but I couldn't. And it is not possible by Data sampling for time statistics , have you any idea how can I do that ?

Thanks in advance.

Regards,
Tanjina.
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Old   September 5, 2013, 03:20
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The area-averaged velocity (and much more, the GUI is quite self-explanatory here) can be created in the "monitors" tab in fluent.

I bet that you can also access custom field functions here.
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Old   September 5, 2013, 09:40
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Quote:
Originally Posted by flotus1 View Post
The area-averaged velocity (and much more, the GUI is quite self-explanatory here) can be created in the "monitors" tab in fluent.

I bet that you can also access custom field functions here.
Hello Flotus,

Thank you very much for your reply.

I tried to plot velocity in every iteration from "Monitors", but is it the area averaged velocity ? It's only showing that "velocity magnitude", that's why I got confused.

I have pipe with 0.2 width and 6 m long. I want to calculate average velocity along 6 m at every node point. Is it possible by "monitors" tab? if not, then is there any other way ? By using that average value I will calculate the mass flow rate along the pipe.

I am sorry, may be it's a silly question..... but I couldn't find out it by myself. Hope you can help.

Thanks in advance.


Regards,

Tanjina
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Old   September 6, 2013, 12:56
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Quote:
I tried to plot velocity in every iteration from "Monitors", but is it the area averaged velocity ? It's only showing that "velocity magnitude", that's why I got confused.
The monitor shows whatever you insert.
Please have a close look at the GUI and the possible settings when adding a new surface monitor. It really is self-explanatory.
There is even a "Mass Flow Rate" report type among the surface monitors...
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Old   September 12, 2013, 09:57
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Originally Posted by flotus1 View Post
The monitor shows whatever you insert.
Please have a close look at the GUI and the possible settings when adding a new surface monitor. It really is self-explanatory.
There is even a "Mass Flow Rate" report type among the surface monitors...

Thank you Flotus for your suggestion. Finally I found my way. Thanks a lot.
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Old   November 16, 2013, 21:56
Default Find area averaged velocity along 3D pipe
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Dear Flotus and All,

Right now I am modelling a 3D pipe surrounded by aggregate. I need to find area averaged velocity along pipe length ( X-axis). According to my understanding I have to find out the area averaged velocity of y axis at every x point.

Is there anyone who can kindly suggest me any idea? I would be really grateful. Thanks in advance.

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Tanjina
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Old   July 26, 2014, 04:25
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hi FAR,please explain about it?
thanks
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