The problem in outputting reaction rates

MFiX
#1

Hi, everyone. I have chose to output reaction rates in VTK file in MFIX 21.2. However, no results about reaction rates are found. Is there something I ignore?
test-press-v1-8MPa.zip (26.4 MB)

#2

I am not able to open your zip file. Please verify and send again.

#3

The file uploaded was actually a rar file, I was able to extract it with unrar. Here’s the contents re-packaged as a zip.

test-press-v1-8MPa.zip (31.2 MB)

1 Like
#4

While running this job I saw a message get printed to the controlling terminal:

mfix - WARNING - Could not find BC

this message is not in any of the logs, and is not printed in the internal GUI console - this is a potential issue (separate from the rrate issue that Yajing reported).

#5

I can confirm the reported behavior. VTK output #2 is configured as Particle data and RX1 rate is checked - this sets the keyword vtk_part_rrate(2,1) = .True.

shot-2021-09-08_17-34-46
shot-2021-09-08_17-34-46474×912 64.6 KB

But looking at the output file BACKGROUND_IC_1_0000.vtp

strings BACKGROUND_IC_1_0000.vtp |grep Name
         <DataArray type="Float32" Name="coordinates" NumberOfComponents="3" format="appended" offset="           0 " />
        <DataArray type="Float32" Name="Diameter" format="appended" offset="        3172" />
        <DataArray type="Float32" Name="Velocity"  NumberOfComponents="3" format="appended" offset="        4232" />
        <DataArray type="Float32" Name="Temperature" format="appended" offset="        7404" />
        <DataArray type="Float32" Name="X_s(1)" format="appended" offset="        8464" />

the reaction rate is not there.

As an experiment I increased nrr - this shouldn’t matter, and it didn’t.

I also tried saving the reaction rate as cell data, as part of VTK output region #1 - this worked. This sets vtk_des_rrate(1,1) = .True. and RRates_RX appears in the VTU file:

shot-2021-09-08_17-34-46
shot-2021-09-08_17-34-46474×912 64.6 KB 

strings BACKGROUND_IC_0000.vtu |grep Name
        <DataArray type="Float32" Name="coordinates" NumberOfComponents="3" format="appended" offset="           0" />
        <DataArray type="Int32" Name="connectivity" format="appended" offset="         976" />
        <DataArray type="Int32" Name="offsets" format="appended" offset="        2004" />
        <DataArray type="Int32" Name="types" format="appended" offset="        2136" />
        <DataArray type="Float32" Name="EP_G" format="appended" offset="        2268" />
        <DataArray type="Float32" Name="P_G" format="appended" offset="        2400" />
        <DataArray type="Float32" Name="Gas_Velocity"  NumberOfComponents="3" format="appended" offset="        2532" />
        <DataArray type="Float32" Name="Gas_temperature" format="appended" offset="        2920" />
        <DataArray type="Float32" Name="H2O_Gas_mass_fractions_1" format="appended" offset="        3052" />
        <DataArray type="Float32" Name="CH4_Gas_mass_fractions_2" format="appended" offset="        3184" />
        <DataArray type="Float32" Name="RRates_RX1" format="appended" offset="        3316" />

So it looks like VTK rrates works for cell data but not particle data.

– Charles

#6

Thanks Charles for converting the zip file.

It is a bug and will be fixed in the next release. In the meantime, if you feel comfortable editing the source code, go to line 469 of model/check_data/check_output_control.f and replace SAVE_DES_RRATES by SAVE_PART_RRATES. The screenshot below shows line 469 (with bug, commented out) and the correct version on line 470

image
image986×590 123 KB

1 Like
#7

Thanks very much for your help!

#8

Thanks very much for your valuable instruction!

#9

Thanks very much! It really helps me.