AMReX-Combustion / PeleC

An AMR code for compressible reacting flow simulations
https://amrex-combustion.github.io/PeleC
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Specification of air as the ONLY working fluid - massfrac #867

Closed SRkumar97 closed 3 weeks ago

SRkumar97 commented 3 weeks ago

Hi, I am trying to run a supersonic boundary layer case over a flat plate, with standard air as the gas. Now the issue I am facing is wrt the mass fractions and gas_IDs of N2 and O2. I want specify clearly that there is only and only air as the gas. Now, I found a case which has got N2 and O2 with mass fractions as that of standard air - the Spray-Multijet testcase. Here, the prob_parm.H has the mass fractions stored in the variables Y_N2 and Y_O2 respectively. And the prob.cpp and prob.H files call for these two variables in massfrac[N2_ID] and massfrac[O2_ID] (e.g. - Spray-Multijet and Spray-Conv)

My doubt is, whether these two IDs are pre-defined in PeleC? In certain cases I'm seeing that an additional mass fraction is also specified with a value of absolute 0.0, (e.g. amrex::Real massfrac[NUM_SPECIES] = {0.0}; in Spray-TG) . But I don't understand this additional statement. I am unable to find any value for NUM_SPECIES in the prob_parm.H.

Would be glad if someone could explain all this and inform what is the correct way to specify air as the only working fluid.

I also came across this case involving air -

https://amrex-combustion.github.io/PeleC/validation/validation.html#counter-flow-diffusion-flame

But I am unable to find a case with a matching name in the RegTests folder.

Thanks for reading!