A standard atmosphere function based on the 1976 Standard Atmosphere returns density, speed of sound, temperature, pressure, and viscosity for a given altitude input up to 86 km.
This function is designed to be useful for those designing and analyzing aircraft and has the following features that hitherto have not been combined in a single standard atmosphere function:
•Input may be a scalar, vector, matrix, or n-dimensional array of altitudes. The function is vectorized and fast for computing atmospheric conditions at a large number of points simultaneously. Especially for n-dimensional problems, it is faster than the built-in atmosisa that comes with the aerospace toolbox.
•Temperature offset option for non-standard atmospheres, e.g analyzing hot day aircraft performance.
•Either SI or imperial units (and easy to set your preferred default).
•Units consistency can be enforced by using the DimensionedVariable class, reducing errors and making code clearer.
•Returns everything needed to easily determine important parameters such as dynamic pressure, Mach number, Reynolds number, stagnation temperature, etc.
•Option for geometric instead of geopotential altitude input.
Examples included in help:
•Create tables of atmospheric properties for a cold, standard, and hot day leveraging 3-dimensional array inputs.
•Find atmospheric properties for an off-standard atmosphere with temperature offset varying degrees sinusoidally with altitude.
•Use the capabilities of the DimensionedVariable class to find some key parameters for an aircraft in flight.
References: ESDU 77022; www.pdas.com/atmos.html