[Maralady]

Hello, I am interested in plotting the mass flow for my study. I found several posts here and I am wondering what is the best way to plot the mass flow (the simplest), I would like to know if there is any way to use the probe utility to plot it, also I was thinking to use the foamcalc to get the Uy at an specific point and then export the data to excel and then calculate the mass flow (This is very doable because I have only 8 time folders). I also found an application to find the mass at the boundaries, but I don't necessarily need the values at the boundaries. Please let me know what you think and your experiences with the utilities or applications that worked for you.

[achyutan]

Hi,
If you are modelling incompressible flow, flux field phi gives the mass flow rate. To be dimensionally correct, you can multiply by the constant rho at all cell values. 'phi' field files would be printed in the time data folders or the solver can be compiled suitably by modifying createFields file.
In compressible flow, flux filed phi is the product rho*A*U.

kind regards

[adarsh tiwari]

hi all

I am relatively new in openFoam, i also tried to calculate the mass flow using

patchIntegrate phi <patch name e.g., inlet>

but the results i got is integrated value (obviously ).

Well, i am interested in knowing the average mass flow rate, because the values from patchIntegrate seems to be irrelevant. One more point i can add here is that, i also tried to check the same for density (rho).

The results i got was shocking, at 298K temperature and 1.2 bar pressure i got air density as 72 kg/m^3 (while in actual it must be in between 1.3 to 1.5). Hence I am doubtful about the results from phi / patchIntegrate.
Even you cant calculate the average phi using

patchAverage phi <patch name>

Please let me know how to get the average and/or accurate values..

Thanks and Regards,
Adarsh Tiwari

[achyutan]

Hi,

I think you did not read my post. I had said phi values are available in 'phi' files in all the time directories. If you don't find them, you can tell me. I will help in recompiling your solver so that it prints phi values.
If you find problems in patchAverage, paste the log of your terminal in your post so I can look into it.

kind regards

[adarsh tiwari]

hi achyutan,
I had already read you post. here is one of the "phi" file is copy-pasted. the entries for this file is ranging from 0 to 741532 for different patches.

For your convinence I am pasting here only few entries out of them. Now, please let me know how to draw a conclusion out of this entries.

dimensions      [1 0 -1 0 0 0 0];

internalField   nonuniform List<scalar> 
741532
(
7.34866e-11
5.35848e-11
7.35022e-11
1.43496e-10
-0.000628996
-0.000829854
4.49086e-05
8.85001e-05
1.07866e-08
-2.62494e-07
-1.02133e-08
6.64273e-09
-5.9366e-11
9.33742e-12
4.77928e-12
6.72974e-11
-6.96929e-11
7.7953e-11
-2.45877e-11
1.51488e-11
0.127367
-1.5513
-1.33506
0.14028
-3.1508e-11
-4.02542e-11
-1.28661e-11
6.42612e-11
-1.95611e-10
5.24948e-11
-2.64997e-11
-1.48069e-09
-3.7489
-7.64645
0.405032
2.11413
-0.268137
-0.443756
-2.17979
0.0423932
0.000540912
-0.000816816
-1.67284e-05
0.000243987
0.394458
3.8371
4.87662
-17.1476
3.42231e-11
1.8289e-10
1.19115e-10
3.91706e-11
-0.132403
-2.16361
-0.231845
0.596828
-0.12943
0.0420255
-0.693266
0.12811
-4.60303e-06
-9.72786e-07
4.70375e-06
-1.58909e-05
2.17719e-11
2.63638e-11
-1.84239e-11
1.13861e-11
1.77671e-10
-2.90974e-10
-5.06872e-11
9.36851e-11
-1.71434
0.980508
-0.610228
-0.670914
1.62759e-10
1.66046e-10
-1.54781e-10
3.37144e-11
0.308399
11.0725
-0.341861
-12.7285
0.823162
-5.22353
3.21603
-0.04277
0.00457318
0.0184298
-0.111014
4.43391
-12.44
-9.84443
4.34969
0.94575
-0.298902
-0.216718
0.424008
0.0412798
0.0411952
-0.0941513
3.61275e-06
4.07332e-07
-0.000217116
8.87881e-07
0.000189206
-0.00120571
-0.000422116
-0.000390645
0.000573036
-0.00126828
-0.000335175
-0.00016298
1.07907e-05
3.40722e-06
2.96705e-06
-1.87287
0.04564
0.0321497
-0.0420498
6.5993
-16.8056
24.1253
-0.611202
0.0119244
-0.0523001
0.0181049
0.00010904
8.37369e-05
-0.000617414
3.48738e-06
-3.84514e-12
3.40813e-11
1.48863e-11
2.17085e-11

   EGR_INLET
    {
        type            calculated;
        value           nonuniform List<scalar> 
195
(
-33.1895
-20.1205
-9.20753
-15.591
-8.31813
-17.028
-31.5845
-16.1646
-18.2068
-16.6869
-5.75538
-27.6886
-6.09544
-37.1799
-15.9967
-6.06365
-6.76409
-29.7813
-13.7578
-10.2902
-15.7617
-12.0426
-32.6587
-15.252
-25.8224
-17.0014
-19.0241
-23.5425
-22.4014
-22.1567
-24.4315
-27.224
-24.4773
-19.4257
-14.097
-17.7076
-14.5912
-13.1132
-29.2521
-34.6977
-15.9831
-25.4074
-15.178
-19.7679
-17.7304
-8.47228
-18.1841