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 burgerma61399 January 16, 2019 09:35

Simulating convection depending on density model

Hey everybody,
currently i´m working on my Bachelor-these which is a CFD Simulation of an oven with a constant flow in and out.
One step is to look at the influence of the natural convection of the flow field. The reynolds number inside is pretty low without the convection (Re= 60)
The temperature between the flow at the Inlet and the heated wall is very high. (1000 K)
Now for the natural convection i need to set a density model.
I read a lot about the ideal gas, the incompressible ideal gas and the boussinesq model but nothing specific to my case and which one fits the best.
I guess the boussinesq is wrong because of the high difference in temperature. And because the of that i guess that the pressure difference inside the oven will be to significant to just use the incompressible model...
Can anybody correct me or got a solution for this problem?!

 LuckyTran January 16, 2019 11:59

Nobody can tell you because these are different ways of modeling. You choose what you want.

If you want the results to look like reality, then choose ideal gas since that most closely mimics reality. There are reasons people use the incompressible ideal gas law and Boussinesq and that's why those models exist.

Which one fits best is entirely subjective and depends on the goal. If your goal is to model this case using the Boussinesq model, then you fail that goal by using ideal gas. What is the objective?

 burgerma61399 January 17, 2019 05:02