Aerospace Blockset

ISA Atmosphere Model

Implement the International Standard Atmosphere (ISA)

Library

Environment/Atmosphere

Description

The ISA Atmosphere Model block implements the mathematical representation of the international standard atmosphere values for ambient temperature, pressure, density, and speed of sound for the input geopotential altitude.

The ISA Atmosphere Model block icon displays the input and output metric units.

Dialog Box

Change atmospheric parameters

Select to customize various atmospheric parameters to be different from the ISA values.

Inputs and Outputs

The input is geopotential height.

The four outputs are temperature, speed of sound, air pressure, and air density.

Assumptions and Limitations

Below the geopotential altitude of 0 km and above the geopotential altitude of 20 km, temperature and pressure values are held. Density and speed of sound are calculated using a perfect gas relationship.

References

[1] U.S. Standard Atmosphere, 1976, U.S. Government Printing Office, Washington, D.C.

See Also

COESA Atmosphere Model, Lapse Rate Model

Invert 3x3 Matrix

Lapse Rate Model