Far-field noise and internal modes from a ducted propeller at simulated aircraft takeoff conditions

  title={Far-field noise and internal modes from a ducted propeller at simulated aircraft takeoff conditions},
  author={Richard P. Woodward and Lawrence A. Bock and Laurence J. Heidelberg and David G. Hall},
The ducted propeller offers structural and acoustic benefits typical of conventional turbofan engines while retaining much of the aeroacoustic benefits of the unducted propeller. A model Advanced Ducted Propeller (ADP) was tested in the NASA Lewis Low-Speed Anechoic Wind Tunnel at a simulated takeoff velocity of Mach 0.2. The ADP model was designed and manufactured by the Pratt and Whitney Division of United Technologies. The 16-blade rotor ADP was tested with 22- and 40-vane stators to achieve… 

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