Learning Forum

[azhao]

For example, if I want to get the total mass of injected DPM spray droplet particles which are ended up suspended in the fluid domain, to compare the total mass of accumulated DPM wall particles that form the liquid film. Although I checked section 20.8. Postprocessing for the Discrete Phase of the Fluent user guide, I did not find a similar function of doing this...

[DrAmine]

I think that should be feasible with dpm surrmary or by using dpm report definitions and sum report of film mass.

[azhao]

Hi, DrAmine Thank you for the reply. I checked the DPM summary as follows:
----------------------------------------------------------------------
(*)- Summary for Injection:
(*)- injection-0
(*)
Total number of parcels : 11764016
Total number of particles : 6.731433e+09
Total mass : 4.184355e-03 (kg)
Overall RR Spread Parameter : 2.826338e+00
Maximum Error in RR fit : 9.837324e-02
Overall RR diameter (D_RR): 7.304116e-05 (m)
Maximum RMS distance from injector : 1.809767e-01 (m)
Maximum particle diameter : 1.000000e-04 (m)
Minimum particle diameter : 1.000000e-06 (m)
Overall mean diameter (D_10): 1.606538e-06 (m)
Overall mean surface area (D_20): 4.982076e-06 (m)
Overall mean volume (D_30): 1.076710e-05 (m)
Overall surface diameter (D_21): 1.545005e-05 (m)
Overall volume diameter (D_31): 2.787421e-05 (m)
Overall Sauter diameter (D_32): 5.028929e-05 (m)
Overall De Brouckere diameter (D_43): 6.353207e-05 (m)
---------------------------------------------------------
Also the DPM report function, there is no option to do the sum for only the particles without on-wall flags. And there is no wall film... option for the field variable.

[DrAmine]

DPM Summary from Particle Tracks or DPM Extended Summary and not the report Summary of particles.

[DrAmine]

So verified in the manual (assuming all users will do the same). You can create built-in DPM Report Definitions for DPM Film Mass and Any DPM Particle suspended in the domain: I guess that is actually what you want to achieve.

[azhao]

Thank you for the answer, DPM extended summary gives the information I want, the problem is solved.

FateNumberElapsed Time (s)Injection, Index
MinMaxAvgStd DevMinMax
-------------------- ---------- ---------- ---------- -------------------- --------------------
in Fluid53562312.000e-051.260e+005.335e-013.661e-01injection-2 94556617injection-2370
in Film157051811.420e-031.260e+006.756e-013.814e-01injection-1 94452125injection-1810
Trapped - Zone 11419234291.676e-031.259e+005.582e-020.000e+00injection-20injection-20
Trapped - Zone 1244861.622e-021.052e+005.842e-020.000e+00injection-00injection-00
Trapped - Zone 13214295.165e-031.256e+005.463e-020.000e+00injection-00injection-00
----------
Net63010756

Injected+Inserted63010756
Injected62952640
Inserted58116

(*)- Mass Transfer Summary -(*)

FateMass (kg)
InitialFinalChange
-------------- ---------- ----------
in Fluid1.218e-031.218e-030.000e+00
in Film6.248e-036.248e-030.000e+00
Trapped - Zone 113.164e-023.164e-020.000e+00
Trapped - Zone 125.374e-075.374e-070.000e+00
Trapped - Zone 131.770e-061.770e-060.000e+00
-------------- ---------- ----------
Net3.911e-023.911e-020.000e+00
Injected3.911e-02

(*)- Energy Transfer Summary -(*)

FateEnergy (J)
InitialFinalChange
-------------- ---------- ----------
in Fluid4.383e+015.761e+011.378e+01
in Film2.248e+023.147e+028.993e+01
Trapped - Zone 111.138e+031.152e+031.383e+01
Trapped - Zone 121.933e-021.933e-02 -1.398e-06
Trapped - Zone 136.367e-026.385e-021.842e-04
-------------- ---------- ----------
Net1.407e+031.524e+031.175e+02
Injected1.407e+03

But I also encountered a strange problem as described below.
I used the following settings to get the statistics information of all on wall particles, then I used a Python script with Pandas to sum the particle mass, which gives me the result 0.001231 kg, which is different from the value given by the DPM extended summary, 0.00625kg, why is that?