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Sileno March 26, 2005 09:10

Flow rates
What is the best way of measuring the flow rate in a given point or plane? It is a turbulent flow inside a low rise building with no heat transfer.


Mark Russell April 1, 2005 16:16

Re: Flow rates
Your question is slightly vague. Are you talking about an experimental procedure or from the CFD predictions?

Sileno April 1, 2005 16:40

Re: Flow rates
I am talking about measuring it from the CFD analysis, after run the VRViewer.

Mark Russell April 4, 2005 03:47

Re: Flow rates
Your question seems un-clear. Is this for a cfd run or an exprimental (real world) situation?

Mark Russell April 4, 2005 03:53

Re: Flow rates
Long winded but ...

If you know the velocity 'normal' to each cell, then the product of the cells normal velocity and area will give the volumetric flow rate across that cell.

Sum these for a plane and you will have the volumetric flow rate accross that plane.

tj April 5, 2005 03:39

Re: Flow rates
Sileno, Heres the inform formula that I use to calculate flow rates where FLXS is a user defined object over which the desired flow rate calculation is made and MASS is a user defined object covering the whole domain. Probably better ways of storing, i.e one can print in result file. Check inform lecture for more information.

Regards inform1begin (STORED AREN is ANORTH with IF(ISWEEP.EQ.1) ) (MAKE MSUM is 0.0) (STORE1 MSUM is 0.0 with SWPFIN) (STORE1 MSUM at FLXS is SUM(AREN*V1*1.189) with SWPFIN) (STORED of MFXS AT MASS is MSUM) inform1end

Sileno July 29, 2005 21:02

Re: Flow rates
Dear TJ,

I appreciate your help concerning the use of Inform formula to calculate the flow rate through a determined area or surface. I have tried your expression, but I don't know how to activate the flow rate data produced by Inform formula. Also, I would like to view such information (flow rate) at the monitor display during solution iterations and to print this information to a HD file.

Thanks for any help.


renti October 12, 2005 04:44

Re: Flow rates *NM*

İLKE UYSAL December 17, 2005 07:46

Re: Flow rates
how can we sketch a plot of the volumetric flow rate Q and viscosity for flow through a circular pipe at constant P , density and R. please indicate regions of laminar and turbulent flow

İLKE UYSAL June 1, 2006 07:09

Re: Flow rates *NM*

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