US Standard Atmosphere Equation 1

[bstjs]

I am looking for an equation (using the US standard atmosphere) that will allow me to calculate pressure at any altitude in the troposphere (< 11km) when I know the temperature and pressure at another altitude. Standard temperature lapse rate (-6.5K/km) can be assumed or different value to be input.

 

[airmail]

Hi bstjs.
I know the expression that gives you the relation between pressure at an altitude "z" for ISA (International standard atmosphere). I suppose that it be the same as US standard atmosphere. Here it goes:

Pz=Po*[(Tz/To)^(-g/R*k)]

Being:
Pz: pressure at a determined height (m)
Po: pressure at sea level (101325 N/m^2)
Tz: temperature at "z" height. In troposphere: Tz=To+k*z
To: temperature at sea level (288 K is used)
g: gravity (9.8 m/s^2)
R: gas constant (In air medium, take 287 m^2/(s^2)K
k: constant value ; take -6.5*(10^(-3)) K/m

I hope it be useful.

 

[bstjs]

In my case,I don't want to assume stamdard temperature and pressure at sea level (since this is usually not the case). I wish to use the information I have to improve my estimate of pressure at any other height (including sea level).

 

[vorwald]

This link has a set of equations for standard atmosphere in the lower altitude, see page 4.

http://web.usna.navy.mil/~dfr/flttst0.pdf

Here is another link

http://wahiduddin.net/calc/density_altitude.htm