Peng-Robinson EoS

[Xavi de Bonis]

Hello there,

I have been using cantera for a while now and as of late I have starting simulating conditions in rocket engines. However, due to the high pressure inside the combustion chambers, supercritical conditions of the fluid are very common, therefore real-gas EoS must be used. Initially I though about adding the Peng-Robinson EoS to the source code, but after some research I have found it is already implemented in the code and can be found in https://github.com/Cantera/cantera/blob/main/src/thermo/PengRobinson.cpp. Therefore, my question is: how can I use it? I have searched in the internet but found nearly no information besides the class reference. I want it to calculate H2O2 1D counterdiffusion flames at around 100 bar, so if any extra commands besides setting the EoS should be applied (like changing the mixing model for example) i would really appreciate the help.

Thank you,

Xavi

[Ray Speth]

Hi,

I’d suggest starting by taking a look at the example that uses the Redlich-Kwong EoS, NonIdealShockTube.py as the requirements are similar. This example uses the input file nDodecane_Reitz.yaml, which has species definitions that include both the ideal gas thermodynamic data as well as the extra Redlich-Kwong coefficients. The method for specifying Peng-Robinson coefficients is similar, and is described in the YAML Input Documentation. As mentioned in the NonIdealShockTube.py example, one of the challenges here is the need to get critical state information for radicals, but the reference provided there should help.

Regards,
Ray

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