Comparison of Semi-Empirical Noise Models with Flyover Measurements of Operating Aircraft

Comparison of Semi-Empirical Noise Models with Flyover Measurements of Operating Aircraft

Vieira, A.E. (TU Delft Aircraft Noise and Climate Effects)
von den Hoff, B. (TU Delft Aircraft Noise and Climate Effects)
Snellen, M. (TU Delft Aircraft Noise and Climate Effects)
Simons, D.G. (TU Delft Aircraft Noise and Climate Effects)

2022

The contribution of the engine and the airframe to the total noise generated by an aircraft varies with the operating conditions. Semi-empirical models are able to account for such variations but require detailed engine and airframe data as input that is not readily available for most aircraft types and operations. This hinders the validation of these models through comparison between predictions and experimental data. This work investigates the sensitivity of semi-empirical models of engine and airframe noise to slight variations of the input data, representative of uncertainties in geometrical parameters and variability of the aircraft operating conditions during flyovers. In addition, the predictions are compared to measurements of A320, A330, and B777 landings and departures. This, together with the sensitivity analysis, indicates frequency regions where a mismatch between measurements and predictions exists. The deviation between predictions and measurements for landings can be partially explained by the underestimation of the sound pressure level of the higher harmonics of the fan. For takeoff, the models predict lower levels than measured. This is hypothesized to be associated with jet-installation noise, which is not accounted for in the semi-empirical models. The predicted spectra of the Airbus A320 and A330 were adjusted to account for jet installation noise, using levels available in the literature. This resulted in a better agreement between modeled and measured spectra at low frequencies.

Microphone array
Aircraft noise
Prediction model
Operational aircraft
Noise measurement

http://resolver.tudelft.nl/uuid:5fdb1b39-6a23-4a85-95e5-698cfe31abdd

https://doi.org/10.2514/1.C036387

2023-07-01

0021-8669

Journal of Aircraft: devoted to aeronautical science and technology, 59 (6), 1574-1587

Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.

Institutional Repository

journal article

© 2022 A.E. Vieira, B. von den Hoff, M. Snellen, D.G. Simons