Air density temperature (in kelvin) polynomial function

[EslamHafez]

Hello
I want the polynomial function of air density temperature in kelvin to use it in ansys fluent to model displacement ventilation that is based on natural convection

 

[rb1957]

curve fit to the data. BTW, what is "air density temperature" ? "air density" I understand (but not in degrees Kelvin) "air temperature" in degrees kelvin makes sense. And of course degrees kelvin is the same as degrees celsius with a constant term added.

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

 

[Latexman]

What's wrong with the ideal gas equation?

PV = nRT

and

[ρ] = P(MW)/RT.

IMHO, flow calculations are not so exact to justify the complexity of a polynomial fit to air density.

Good Luck,
Latexman

 

[rb1957]

doesn't work well with the atmosphere, as density changes with altitude.

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

 

[IRstuff]

Just a nitnoid here; the SI unit for absolute temperature is the kelvin, no degrees. Degrees Celsius is the relative temperature unit.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

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[3DDave]

Kelvin - earned the capital K.

 

[IRstuff]

the unit is the kelvin (K)

https://www.nist.gov/pml/owm/si-units-temperature

even NIST's page is ambiguous. see page 4 of

https://physics.nist.gov/cuu/pdf/sp811.pdf

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

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[SWComposites]

OP - just Google “air density vs temperature”

 

[rb1957]

yeah, I read the question from my perspective. But I don't think he means that. But rather changes at sealevel.

So Latexman, or SWC

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.