Generate discrete wind gust
Aerospace Blockset / Environment / Wind
The Discrete Wind Gust Model block implements a wind gust of the standard “1-cosine” shape. This block implements the mathematical representation in the Military Specification MIL-F-8785C [1]. The gust is applied to each axis individually, or to all three axes at once. You specify the gust amplitude (the increase in wind speed generated by the gust), the gust length (length, in meters, over which the gust builds up) and the gust start time. For more information on the gust shape, see Algorithms.
The Discrete Wind Gust Model block can represent the wind speed in units of feet per second, meters per second, or knots.
This figure shows the shape of the gust with a start time of zero. The parameters that govern the gust shape are indicated on the diagram.
To assess airplane response to large wind disturbances, you can use the discrete gust singly or in multiples.
The mathematical representation of the discrete gust is:
where Vm is the gust amplitude, dm is the gust length, x is the distance traveled, and Vwind is the resultant wind velocity in the body axis frame.
[1] U.S. Military Specification MIL-F-8785C, November 5, 1980.
Dryden Wind Turbulence Model (Continuous) | Dryden Wind Turbulence Model (Discrete) | Von Karman Wind Turbulence Model (Continuous)