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Helicopter external noise prediction and correlation with flight test
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Gupta, B. P. |
| Copyright Year | 1978 |
| Description | Mathematical analysis procedures for predicting the main and tail rotor rotational and broadband noise are presented. The aerodynamic and acoustical data from Operational Loads Survey (OLS) flight program are used for validating the analysis and noise prediction methodology. For the long method of rotational noise prediction, the spanwise, chordwise, and azimuthwise airloading is used. In the short method, the airloads are assumed to be concentrated at a single spanwise station and for higher harmonics an airloading harmonic exponent of 2.0 is assumed. For the same flight condition, the predictions from long and short methods of rotational noise prediction are compared with the flight test results. The short method correlates as well or better than the long method. |
| File Size | 711836 |
| Page Count | 13 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19780024886 |
| Archival Resource Key | ark:/13960/t1mh2dr0d |
| Language | English |
| Publisher Date | 1978-08-01 |
| Access Restriction | Open |
| Subject Keyword | Acoustics Flight Tests Noise Reduction Aircraft Noise Helicopters Pollution Control Performance Prediction Noise Pollution Prediction Analysis Techniques Rotary Wings Aerodynamic Loads Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
