PDF Mixture thermal conductivity

HorstvanGrass · November 10, 2019, 04:07

Hi there,
I would like to know how physical accurate can be a constant thermal conductivity in a PDF mixture for a combustion. It should depend on temperature pressure and mass fraction. So is it a start value for an interpolation or is it a hard constant. In case if it's the latter, the simulation can't be accurate...
thx in advance!

LuckyTran · November 10, 2019, 12:17

Accuracy is not binary. It depends how much accuracy you want.
Furthermore, the goal of models is not always to produce accurate results but to test theories. Accuracy is not even a concern for these simulations.

Consider that the Ideal gas model is not accurate, but A LOT of people use it anyway.

If you need the enhanced accuracy, and you the modeler should know this need, then use better models.

November 10, 2019, 04:07	PDF Mixture thermal conductivity	#1
HorstvanGrass Member Horst van Gras Join Date: Oct 2018 Posts: 45 Rep Power: 7	Hi there, I would like to know how physical accurate can be a constant thermal conductivity in a PDF mixture for a combustion. It should depend on temperature pressure and mass fraction. So is it a start value for an interpolation or is it a hard constant. In case if it's the latter, the simulation can't be accurate... thx in advance!

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November 10, 2019, 12:17		#2
LuckyTran Senior Member Lucky Join Date: Apr 2011 Location: Orlando, FL USA Posts: 5,672 Rep Power: 65	Accuracy is not binary. It depends how much accuracy you want. Furthermore, the goal of models is not always to produce accurate results but to test theories. Accuracy is not even a concern for these simulations. Consider that the Ideal gas model is not accurate, but A LOT of people use it anyway. If you need the enhanced accuracy, and you the modeler should know this need, then use better models.