Numerical propagation of aircraft en route noise
Open Access
- Author:
- Poulain, Kieran
- Graduate Program:
- Acoustics
- Degree:
- Master of Science
- Document Type:
- Master Thesis
- Date of Defense:
- November 17, 2011
- Committee Members:
- Victor Ward Sparrow, Thesis Advisor/Co-Advisor
Victor Ward Sparrow, Thesis Advisor/Co-Advisor - Keywords:
- outdoor sound propagation
ray tracing
aircraft en route noise - Abstract:
- The impact of aircraft noise has traditionally been oriented towards airport community noise issues. However, the emerging concern of noise issues in quiet natural areas such as National Parks has lately shifted some of the research efforts towards the propagation of noise from high altitude aircraft (over 18,000 feet), technically defined as aircraft en route noise. Indeed, the future re-emerging of open-rotor propulsion systems which would reduce the fuel emissions by as much as 30%, could also potentially increase the emitted noise. Such a configuration calls for new methods in order to determine the transmission loss between source and receiver, compared with a traditional community noise issue. Additionally, any numerical prediction should include a realistic and altitude-dependent weather profile along such long propagation paths, which directly affects how wave fronts bend as well as the total atmospheric absorption. AERNOM, which stands for “Advanced En Route NOise Model”, is a ray tracing numerical prediction scheme that was designed to handle such a geometry in order to account for the atmospheric effects in predicting en route noise ground contours. The performance of AERNOM was further compared to FAA's Integrated Noise Model, Penn State's Hybrid Propagation Model, as well as Delta's NORD 2000 for simple test cases representing a stable en route overflight path. [Work supported by the John A. Volpe National Transportation Systems Center. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of Volpe or PARTNER sponsoring organizations.]