## Blocklibrary WINDLIB

The FDC blocklibrary WINDLIB contains sublibraries with Simulink models of wind and atmospheric turbulence. The models determine external atmospheric disturbances, which can be connected to a non-linear aircraft model (e.g. Beaver), because the results are determined in terms velocity components within the body-fixed reference frame of the aircraft. For more details about the underlying theory, see the references at the end of this help-text.

The Wind models sublibrary contains the following blocks:

- BLwind
  Wind profile in Earth's Boundary Layer
- Cwind
  Constant horizontal wind

The Atmospheric turbulence models sublibrary contains the following blocks:

- turb1
  Example system which combines UDRYD1, VDRYD1, and WDRYD1 in one subsystem
- turb2
  Example system which combines UDRYD2, VDRYD2, and WDRYD2 in one subsystem
- UDRYD1
  Longitudinal Dryden filter with constant coefficients
- UDRYD2
  Longitudinal Dryden filter with velocity-dependent coefficients
- VDRYD1
  Lateral Dryden filter with constant coefficients
- VDRYD2
  Lateral Dryden filter with velocity-dependent coefficients
- WDRYD1
  Vertical Dryden filter with constant coefficients
- WDRYD2
  Vertical Dryden filter with velocity-dependent coefficients

### References

Apart from the FDC user-manual, the following references contain more information about the wind and turbulence models:

1. M.O. Rauw: A Simulink environment for Flight Dynamics and Control analysis - Application to the DHC-2 'Beaver', part I: Implementation of a model library in Simulink. Delft University of Technology, September 1993 (also contained in the STAR database of NASA, report number NONP-NASA-SUPPL-DK-94-28027)
2. Approach and Landing Simulation, AGARD report 632, Ames, 1975.