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pips
May10-07, 05:43 AM
How can you calculate density from : altitude temperature and absolute humidity

FredGarvin
May10-07, 06:37 AM
The easiest way is to use a standard atmospheric table like the one here:
http://modelweb.gsfc.nasa.gov/atmos/us_standard.html

http://hypertextbook.com/facts/2000/RachelChu.shtml


If you want to get down and dirty with density calculations, look around for NIST's publication NBSIR 77-1278 The Air Density Equation and the Transfer of the Mass Unit.

Mech. Engineer
May12-07, 10:24 AM
from humidity u can find due point

due point and temp u can find pressure

if the fluid is ideal u can find volume by PV=nRT

if u know pressure and temp u can find spc. volume

from spc.volume and volume u can find mass

from mass and volume u can find density...

FredGarvin
May12-07, 01:58 PM
If you know specific volume, you know the density.