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[98546948]

Hello everyone, some statements described the density of fluids in Fluent help are displayed like this.

So,If I set the density as a function of the temperature, is that the fluid is not compressible by default?

Thanks

sincerely.

[seeta gunti]

Hello,

If you want to model the compressible flows, you need to specify the density as Ideal gas.

If you specify density is a function of temperature, density varies wrt to temperature only but not with pressure. In this case, pressure remains constant almost.

Regards,

Seeta

 

[DrAmine]

Just in addition to Seeta: If you want to model compressible flow the density has to be a function of pressure. So either you follow what Seeta suggested: Ideal Gas or Real Gas or providing a function for density user defined real gas model.Compressible flow are flows with significant change in density. Generally one rely on the Mach number to judge whether compressibility effects are relevant or not. But even at low Mach numbers for some applications compressibility or at least temperature dependency of the density is very important!