[arsadCFD]

Hi


I wanna simulate argon ion transport with stationary neutral argon atoms in the background? Is it possible to simulate this in SU2? Could you please give me some guidance on this? The geometry will be simple rectangular duct/step

[bigfootedrockmidget]

for hypersonic flows? Then use the NEMO framework.

[arsadCFD]

Thanks. It would be weakly compressible flows. Yeah I m trying to figure out NEMO but couldn't understand yet how to simulate argon ions dynamics with stationary neutral argon background. Any suggestions in this regard will be much appreciated!

[arsadCFD]

Originally Posted by arsadCFD

Thanks. It would be weakly compressible flows. Yeah I m trying to figure out NEMO but couldn't understand yet how to simulate argon ions dynamics with stationary neutral argon background. Any suggestions in this regard will be much appreciated!

Hi Any suggestion on this please?

[CatarinaGarbacz]

Hello,


by "stationary neutral argon background" you mean neutral argon freestream that ionizes?

Yes you can do this with NEMO. What exactly do you need to know?

To use NEMO with mixtures different than air-5,air-7,N2 and neutral Argon, you need to use mutation++ which is coupled to SU2-NEMO.

In the SU2/TestCases/nonequilibrium/viscwedge_mpp/ you have an example of a case using mutation++


In SU2/TestCases/nonequilibrium/visc_cylinder/ you have an example of ionization for air-7 without mutation++

Combining these two examples, you can set a case for ionization with mutation++.

To have argon allowing for ionization, you need to create your own mixture and mechanism of reaction files, as per the examples given in mutationpp/data/mixtures and mutationpp/data/mechanisms

These are initial guidelines but perhaps something to start with and feel free to ask more specific questions if you need help

[arsadCFD]

Hi Catarina

Thank you so much for your guidance so far. It did help. Much appreciated!

I ran the following cases suggested by you:

SU2/TestCases/nonequilibrium/visc_cylinder/ using SU2_NEQ
SU2/TestCases/nonequilibrium/viscwedge_mpp/ using MUTATIONPP

Both the cases ran quite well.

CASE-1

Then I took the viscous cylinder case (SU2/TestCases/nonequilibrium/visc_cylinder/) with flow conditions remaing the same and changed the gas mixture to N2,N2+,N,N+ and e- using mutationpp https://github.com/mutationpp/Mutati...input-files.md

the mixture (N2_mix.xml) and mechanisms (N2_mix.xml) file are attached for reference.

The only change to cfg file was:

GAS_MODEL= N2_mix
GAS_COMPOSITION= (0.99, 0.001, 0.001, 5e-13, 5e-13)
TRANSPORT_COEFF_MODEL= WILKE
CFL_NUMBER= 0.1 (tried 0.001)

I get the following error:


xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
------------------------------ Begin Solver -----------------------------

Simulation Run using the Single-zone Driver
Warning, didn't converge temperatures: f = 4.8595e+09
Warning, didn't converge temperatures: f = 4.8595e+09
Warning, didn't converge temperatures: f = 4.8595e+09
Warning, didn't converge temperatures: f = 4.8595e+09
Warning, didn't converge temperatures: f = 4.8595e+09
Warning, didn't converge temperatures: f = 4.8595e+09
Warning. The initial solution contains 33344 points that are not physical.
Warning!! Instances of NaN in the following source terms:
Axisymmetry: 4962
Chemical: 4962
Vib. Relax: 4962
Warning!! Instances of NaN in the following source terms:
Axisymmetry: 5419
Chemical: 5419
Vib. Relax: 5419
Warning!! Instances of NaN in the following source terms:
Axisymmetry: 5431
Chemical: 5431
Vib. Relax: 5431
Warning!! Instances of NaN in the following source terms:
Axisymmetry: 5422
Chemical: 5422
Vib. Relax: 5422
Warning!! Instances of NaN in the following source terms:
Axisymmetry: 5420
Chemical: 5420
Vib. Relax: 5420
Warning!! Instances of NaN in the following source terms:
Axisymmetry: 5422
Chemical: 5422
Vib. Relax: 5422


Error in "void CSolver::SetResidual_RMS(const CGeometry*, const CConfig*)":
-------------------------------------------------------------------------
SU2 has diverged (NaN detected).
------------------------------ Error Exit -------------------------------

xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx



CASE-2

e-, Ar+, Ar mixture for above vscous cylinder case. For now, I m running this for viscous cylinder case, but need to run for CD nozzle and eventually rectangular/step geometry. This is my target simulation actually. The simultions are runing for viscolus cylinder case,but the values printed on screen aren't changing much. Here is the snapshot after 10k iterations:

| 9516| -16.835949| -5.173191| -4.650124| 2.702567| -2.336905| -0.008635| 0.000000| 7.0367e+04|
| 9517| -16.846160| -5.183402| -4.660334| 2.691006| -2.333945| -0.008635| 0.000000| 7.0362e+04|
| 9518| -16.843025| -5.180267| -4.657200| 2.694214| -2.330853| -0.008635| 0.000000| 7.0356e+04|
| 9519| -16.842097| -5.179339| -4.656272| 2.695318| -2.320753| -0.008635| 0.000000| 7.0351e+04|
| 9520| -16.839410| -5.176652| -4.653585| 2.698406| -2.323075| -0.008635| 0.000000| 7.0346e+04|
| 9521| -16.843255| -5.180497| -4.657429| 2.694412| -2.340916| -0.008635| 0.000000| 7.0340e+04|
| 9522| -16.845681| -5.182924| -4.659856| 2.691368| -2.342332| -0.008634| 0.000000| 7.0335e+04|
| 9523| -16.850042| -5.187285| -4.664217| 2.686412| -2.332234| -0.008634| 0.000000| 7.0329e+04|
| 9524| -16.837505| -5.174747| -4.651679| 2.700745| -2.317436| -0.008634| 0.000000| 7.0324e+04|
| 9525| -16.837906| -5.175148| -4.652080| 2.700601| -2.303656| -0.008634| 0.000000| 7.0319e+04|
| 9526| -16.833535| -5.170777| -4.647710| 2.705273| -2.300092| -0.008634| 0.000000| 7.0313e+04|
| 9527| -16.831439| -5.168681| -4.645614| 2.707864| -2.288069| -0.008634| 0.000000| 7.0308e+04|
| 9528| -16.831931| -5.169173| -4.646106| 2.707455| -2.286073| -0.008634| 0.000000| 7.0302e+04|
| 9529| -16.827159| -5.164401| -4.641333| 2.712853| -2.288946| -0.008634| 0.000000| 7.0297e+04|
| 9530| -16.823469| -5.160712| -4.637644| 2.716871| -2.266998| -0.008634| 0.000000| 7.0292e+04|
| 9531| -16.833619| -5.170861| -4.647793| 2.704761| -2.287797| -0.008634| 0.000000| 7.0286e+04|
| 9532| -16.837472| -5.174714| -4.651647| 2.700340| -2.310097| -0.008634| 0.000000| 7.0281e+04|
| 9533| -16.840277| -5.177520| -4.654452| 2.697283| -2.317660| -0.008634| 0.000000| 7.0275e+04|

FLUID_MODEL= MUTATIONPP
GAS_MODEL= argon_ion
GAS_COMPOSITION= (5E-13, 0.23, 0.767)
TRANSPORT_COEFF_MODEL= WILKE
CFL_NUMBER= 0.05 (it runs with 0.5 as well, but diverges aftre few thousands of iterations)

I checked the intermediate files pritnted, the mass fraction of e-, Ar+ and Ar, seems to be constant throughout and not changing. Considering ionization, the mass fraction should change right? Do i need to switch on any other parameters ionization? I see some options in master cfg file

[%
% Specify if there is ionization
IONIZATION= NO]

Is there any mistake in mechanism/mixture file format,units etc?I still need to double check arhenius coeeficients as the order of magnitude looks slightly different I'm attaching both mixture/mechanism files here for CASE-1&2

Could you please help me on CASE-1 &2

[CatarinaGarbacz]

Can you attach the 4 input files please:

.cfg
.su2
mix file
mechanism file

[arsadCFD]

Originally Posted by catarinagarbacz

can you attach the 4 input files please:

.cfg
.su2
mix file
mechanism file

N2_MIX_cyl_ion_gy.txt

N2_mix.png

N2_Mechanism.png

[arsadCFD]

Originally Posted by catarinagarbacz

can you attach the 4 input files please:

.cfg
.su2
mix file
mechanism file

ARGON_MIX_cyl_ion_gy.txt

ArgonMix.png

ArgonMechanism.png

[arsadCFD]

Originally Posted by CatarinaGarbacz

Can you attach the 4 input files please:

.cfg
.su2
mix file
mechanism file

.su2 mesh file is same as that on non-equlibrium viscous cylinder located here;
https://github.com/su2code/TestCases.../visc_cylinder