Air density calculation

This function calculates the density of the air

Description

This function calculates the air-density based on the papers:

1)'Equation for the Determination of the Density of Moist Air'
P.Giacomo, Metrologia 18, 33-40 (1982)

2)'Equation for the Determination of the Density of Moist Air'
R.S. Davis Metrologia 29, 67-70 (1992)

Parameters:
   t = ambient temperature (ºC)
  hr = relative humidity [%]
   p = ambient pressure [Pa]

ver 1.0
06/10/2006 Jose Luis Prego Borges
Sensor & System Group, Universitat Politecnica de Catalunya, Spain

• MATLAB release: MATLAB 6.5 (R13)
• Other requirements: matlab 6.5

[Jos x]

Why not vectorize it so you can put in a list of numbers? (simply use .* instead of * etc.)
Why is f0 in the argument list?
The help should mention what "ro" is and in what units it is expressed.
End the calculations with a semi-colon to suppress the display.
For some (most) values ro is negative? Can that be true?
You should check for unphysical inputs (e.g., hr>100%).

[Nanthakarn Udomputtisit]

 

[Niclas -]

Good work! Although the difference is minor, the correct conversion between degrees Celsius and Kelvin is:

t90 / °C = T90/K - 273.15

Check the ITS-90 page on:
http://www.its-90.com/its-90.html

Best regards,
niclas

[paramust juntarakod]

thank you for your work

[riva wahyudi]

good

[riva wahyudi]

good for reference tehnical specification

[Olfert]

missing the temperature and pressure limitations for this function?

I tried to use it to get air density in a simulation of a combustion engine with 1>=hr>=0, but it seems that after 3.5e6Pa and 1500K the function doesn't work. It returns negatives densities. I guess thats the limitations, just so it is here.

other wise great function :D

[Kim DiGiovanni]

 

[Kim DiGiovanni]

Excellent! Easy to use and well developed and cited!