Design and acoustic characterization of a psycho-acoustic listening facility

The design, development, and acoustic characterization of the Psychoacoustic Listening Laboratory (PALILA) recently established at Delft University of Technology are presented in this manuscript. This laboratory comprises a soundproof room with a modular design and specialized audio equipment. Its primary objective is to conduct experimental...

Psychoacoustic model for predicting wind turbine noise annoyance

Noise annoyance caused by wind turbines is a critical issue for the societal acceptance of wind energy. Wind turbine noise exposure is typically assessed using conventional time–averaged metrics, however, the literature suggests that these metrics do not fully capture the sound properties responsible for the perceived noise annoyance. Therefore,...

Comparison of cavity geometries for a microphone array in an open-jet wind-tunnel experiment

This paper analyses the influence of microphone cavity geometry on beamforming measurements with a turbulent boundary layer present on the microphone array. A 16- microphone array was tested in the anechoic open-jet wind tunnel of the Delft University of Technology. The array was placed on a flat plate mounted flush with the exit nozzle of the...

Sound quality metrics applied to aircraft components under operational conditions using a microphone array

Aircraft noise is an increasingly important issue that causes annoyance and complaints for the communities living in the vicinity of airports. The conventional sound metrics (such as the A–weighted sound pressure level) typically used for assessing the impact of aircraft noise often fail to conveniently represent the actual annoyance...

Variability of sound quality metrics for different aircraft types during landing and takeoff

The capacity of airports is limited due to the negative community response to noise. Traditional metrics, such as the A-weighted maximum sound pressure level (Lp;A;max), indicate the overall noise generated by an aircraft flyover but do not provide any information on tonal components or frequency variations in time that are known to affect...

Assessment of the sound quality of wind turbine noise reduction measures

Noise emissions from wind turbines are one of the main issues that the wind energy industry must deal with nowadays. Strict noise regulations often prevent wind turbines to operate at maximum power conditions, causing large losses of power production and, hence, of revenue. Several noise reduction measures have been proposed so far, but the...

Analysis of nose landing gear noise comparing numerical computations, prediction models and flyover and wind-tunnel measurements

The noise emissions of a full-scale nose landing gear, measured in a wind tunnel and obtained from computational simulations, are compared with those of three regional aircraft types recorded in flyover measurements. The results from these three approaches are also compared with the predictions of two airframe noise models (Fink and Guo). The...

Comparison between analog and digital microphone phased arrays for aeroacoustic measurements

Microphone arrays are useful measurement devices for estimating the location and strength of sound sources. Numerous comparative studies have been conducted regarding the performance of acoustic imaging methods in the past, but literature lacks of a systematic investigation on the role of the hardware on the measurements. This research...

Comparing flyover noise measurements to full-scale nose landing gear wind tunnel experiments for regional aircraft

Noise breakdown of landing aircraft using a microphone array and an airframe noise model

Functional Beamforming applied to full scale landing aircraft

Aircraft noise is becoming an increasingly important problem for the aerospace industry and for the residents living in the vicinities of airports. For efforts aiming at reducing aircraft noise levels, it is important to know all the aircraft elements which generate noise and their relative contribution. Experimental measurements with aircraft...

Analysis of landing gear noise during approach

Airframe noise is becoming increasingly important during approach, even reaching higher noise levels than the engines in some cases. More people are a_ected due to low ight altitudes and _xed tra_c routing associated with typical approaches. For most air- craft types, the landing gear system is a dominant airframe noise source. However, this...

Determination of aircraft noise variability using an acoustic camera

Nowadays, aircraft noise is one of the major problems to be dealt with by the aerospace industry and especially suffered by the residents living in the vicinities of airports. The enforcement of noise control environmental laws around airports is hindered due to the large variability observed in the noise levels for flyovers of the same aircraft...

Assessment of aircraft noise sources variability using an acoustic camera

Noise assessment around airports is hampered due to the observed large variability in noise levels for fly-overs of the same aircraft type, which is not considered by the current models. This paper assumes that the noise variability is due to variations in the aircraft emitted noise, neglecting the effect of the variable atmosphere, as previous...