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Uhb demonstrator interior noise control flight tests and analysis
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Cannon, M. R. Druez, P. M. Brock, M. P. Burge, P. L. Tran, B. N. Mathur, G. P. Kimbrough, A. J. Simpson, M. A. |
| Copyright Year | 1989 |
| Description | The measurement and analysis of MD-UHB (McDonnell Douglas Ultra High Bypass) Demonstrator noise and vibration flight test data are described as they relate to passenger cabin noise. The analyses were done to investigate the interior noise characteristics of advanced turboprop aircraft with aft-mounted engines, and to study the effectiveness of selected noise control treatments in reducing passenger cabin noise. The UHB Demonstrator is an MD-80 test aircraft with the left JT8D engine replaced with a prototype UHB engine. For these tests, the UHB engine was a General Electric Unducted Fan, with either 8x8 or 10x8 counter-rotating propeller configurations. Interior noise level characteristics were studied for several altitudes and speeds, with emphasis on high altitude (35,000 ft), high speed (0.75 Mach) cruise conditions. The effectiveness of several noise control treatments was evaluated based on cabin noise measurements. The important airborne and structureborne transmission paths were identified for both tonal and broadband sources using the results of a sound intensity survey, exterior and interior noise and vibration data, and partial coherence analysis techniques. Estimates of the turbulent boundary layer pressure wavenumber-frequency spectrum were made, based on measured fuselage noise levels. |
| File Size | 6690297 |
| Page Count | 194 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19900003882 |
| Archival Resource Key | ark:/13960/t2c876b80 |
| Language | English |
| Publisher Date | 1989-10-01 |
| Access Restriction | Open |
| Subject Keyword | Acoustics Flight Tests Md 80 Aircraft Turboprop Aircraft Sound Transmission Noise Reduction Aircraft Noise Turbulent Boundary Layer Aircraft Compartments Pressure Distribution Turboprop Engines Vibration Tests Noise Spectra Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
