# Ducted Fan Optimization

Blade element momentum theory (BEMT) is used to optimize the rotor blade geometry to maximize thrust for a given power available. Solutions are interated until power required equals power available.

- Rotor is assumed to be contained in duct - no tip losses calculated
- Natural exit area presumed - no thrust increase from expanded exit
- Constant induced velocity field along blade if possible
- Simple momentum theory equations are iterated to solve for thrust and induced velocity and shown for comparison

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## References

Stepniewski, W. Z. (1950). Introduction To Helicopter Aerodynamics, V1. Morton, Pa.

Leishman, J. G. (2008). Principles of Helicopter Aerodynamics. New York, NY.

Stepniewski, W. Z., Keys, C. N. (1984). Rotory-Wing Aerodynamics. Mineola, NY.

Johnson, W. (1980). Helicopter Theory. Princeton, NJ.

Weick, F. E. (1930). Aircraft Propeller Design. York, PA.

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