High-range Real Gas Liquid/Gas Mixing Problem

bicklevov · April 11, 2018, 18:32

I am trying to get a model to converge that uses oxygen with a wide range of pressures and temperatures without going to a 2-phase model. I am modeling liquid injection into a hot gaseous flow.

I have previously worked with the RGP table feature which works well by approximating the liquid and gas Cp and densities, and has been relatively accurate for the purposes I need, as long as I stay well away from the critical point (have kept pressures high).

I realize there is a FORTRAN RGP table generator that does not cluster points around the critical point, and a Python RGP table generator unique to 18.2 that does. Neither of them seem to work once I drop pressures in the model that bring me close to the fluid critical point.

Is there any way with a Peng-Robinson or Redlich-Kwong model to try and model this mixing? I have read the ANSYS model and have set the expert parameter realeos liquid prop to 2, but densities in the cold inlet (which I am approximating to be liquid) are still too high. I am making the overall equation of state a gas.

lyfflynice · July 22, 2018, 03:46

Dear Bicklevov,
How to use the RGP file define the liquid properities? can you give me a format or example file? I will appreciate it!
Best regrad!

April 11, 2018, 18:32	High-range Real Gas Liquid/Gas Mixing Problem	#1
bicklevov New Member artfoster Join Date: Apr 2018 Posts: 1 Rep Power: 0	I am trying to get a model to converge that uses oxygen with a wide range of pressures and temperatures without going to a 2-phase model. I am modeling liquid injection into a hot gaseous flow. I have previously worked with the RGP table feature which works well by approximating the liquid and gas Cp and densities, and has been relatively accurate for the purposes I need, as long as I stay well away from the critical point (have kept pressures high). I realize there is a FORTRAN RGP table generator that does not cluster points around the critical point, and a Python RGP table generator unique to 18.2 that does. Neither of them seem to work once I drop pressures in the model that bring me close to the fluid critical point. Is there any way with a Peng-Robinson or Redlich-Kwong model to try and model this mixing? I have read the ANSYS model and have set the expert parameter realeos liquid prop to 2, but densities in the cold inlet (which I am approximating to be liquid) are still too high. I am making the overall equation of state a gas.

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July 22, 2018, 03:46		#2
lyfflynice New Member Yafei Li Join Date: Jul 2018 Location: CHIAN Posts: 16 Rep Power: 7	Dear Bicklevov, How to use the RGP file define the liquid properities? can you give me a format or example file? I will appreciate it! Best regrad!