David A. Topol and Douglas C. Mathews

Pratt & Whitney, East Hartford, Connecticut

Rotor Wake/Stator Interaction Noise

Prediction Code

Technical Documentation and User’s Manual

NASA/CR—2010-216818

December 2010
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David A. Topol and Douglas C. Mathews

Pratt & Whitney, East Hartford, Connecticut

Rotor Wake/Stator Interaction Noise

Prediction Code

Technical Documentation and User’s Manual

NASA/CR—2010-216818

December 2010

National Aeronautics and

Space Administration

Glenn Research Center

Cleveland, Ohio 44135

Prepared under Contract NAS3–25952, Task 10
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This work was sponsored by the Fundamental Aeronautics Program 

at the NASA Glenn Research Center.

Level of Review: This material has been technically reviewed by NASA expert reviewer(s).
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4. TITLE AND SUBTITLE

Rotor Wake/Stator Interaction Noise Prediction Code 

Technical Documentation and User's Manual

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NAS3-25952 

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6. AUTHOR(S)

Topol, David, A.; Mathews, Douglas, C. 

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10 

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Pratt & Whitney 

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13. SUPPLEMENTARY NOTES

14. ABSTRACT

This report documents the improvements and enhancements made by Pratt & Whitney to two NASA programs which together will calculate 

noise from a rotor wake/stator interaction. The code is a combination of subroutines from two NASA programs with many new features 

added by Pratt & Whitney. To do a calculation V072 first uses a semi-empirical wake prediction to calculate the rotor wake characteristics at 

the stator leading edge. Results from the wake model are then automatically input into a rotor wake/stator interaction analytical noise 

prediction routine which calculates inlet aft sound power levels for the blade-passage-frequency tones and their harmonics, along with the 

complex radial mode amplitudes. The code allows for a noise calculation to be performed for a compressor rotor wake/stator interaction, a 

fan wake/FEGV interaction, or a fan wake/core stator interaction. This report is split into two parts, the first part discusses the technical 

documentation of the program as improved by Pratt & Whitney. The second part is a user's manual which describes how input files are 

created and how the code is run. 

15. SUBJECT TERMS

Ducted fans; Noise 

16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF

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51 

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