V/STOL ROTARY PROPULSOR NOISE PREDICTION MODEL UPDATE AND EVALUATION

The V/STOL Rotary Propulsor Noise Prediction Model developed under contract DOT-FA74WA-3477 was updated and evaluated. In the first phase, a literature review was conducted to identify and evaluate high quality noise measurements of propeller, variable pitch fan, fixed pitch fan, helicopter, lift fan, core engine, and jet noise for the preparation a of data base with emphasis on recent measurements of in-flight propulsors. In the second phase, the effects of forward flight on V/STOL propulsor noise were evaluated and the noise prediction model was improved to give better agreement with current measurements. Lastly, the performance of the noise prediction methodology was evaluated by comparison of calculations with measurements of propulsor noise from the data base. Although certain aspects of the measured propulsor noise, such as installation and ground reflection effects, caused discrepancies between measured and calculated levels (the calculations assume uninstalled propulsors under free-field conditions), the general correlation was good. Typical correlation between measured and calculated one-third octave band levels was + or - 5 dB and between measured and calculated dB(A), PNL, PNLT, and EPNL was + or - 3 dB.

• Supplemental Notes:
  • Update to Rept. nos. FAA-RD-76-49-1 through FAA-RD-76-49-3 dated May 76, AD-A027 389, AD-A027 390 and AD-A027 363.
• Corporate Authors:

  United Technologies Corporation

  United Technologies Building
  Hartford, CT  United States  06101

  Federal Aviation Administration

  William J. Hughes Technical Center, Airport Technology Research and Development Branch
  Atlantic City International Airport
  Atlantic City, NJ  United States  08405
• Authors:
  • Magliozzi, B
• Publication Date: 1979-12

Media Info

• Pagination: 233 p.

Subject/Index Terms

• TRT Terms: Accuracy; Acoustic measuring instruments; Acoustics; Aircraft noise; Cavitation noise; Computer programs; Databases; Engines; Helicopters; Jet engines; Jet propelled aircraft; Lift fans; Mathematical prediction; Noise; Rotors; STOL aircraft; Turbofan engines; Variable pitch propellers
• Old TRIS Terms: Acoustic measurement; Engine noise; Jet engine noise; Jet plane noise; Short takeoff aircraft; Tilt
• Subject Areas: Aviation; Data and Information Technology; Environment; Vehicles and Equipment;

Filing Info

• Accession Number: 00313947
• Record Type: Publication
• Source Agency: National Technical Information Service
• Report/Paper Numbers: FAA-RD-79-107
• Files: NTIS, USDOT
• Created Date: Jul 22 2002 12:00AM