Papers by Nico van Oosten
INCAS Buletin, Dec 10, 2012
Studies of impact noise have traditionally focused on landing and takeoff procedures in the airpo... more Studies of impact noise have traditionally focused on landing and takeoff procedures in the airports vicinity. Beside these studies, en-route noise is considered an issue when we talk about noise in natural reservation or other populated sensitive areas and when it comes to designing a new aircraft engine. In these cases, the studies are focusing on the impact at ground level of the en route noise produced by aircraft at all the flights stages. This paper presents the results of the measurement performed for an A320 aircraft when flying en-route and the impact map for a flight from Bucharest-Sofia-Bucharest (OTP-SOF-OTP).
Zenodo (CERN European Organization for Nuclear Research), Feb 18, 2022
The main purpose of this research is to assess the impact of aircraft noise around an airport con... more The main purpose of this research is to assess the impact of aircraft noise around an airport considering spatial and temporal variations in the population. The concept of dynamic airport noise mapping has been demonstrated on Ljubljana airport case study. Detailed population mobility information for Slovenia were retrieved from a survey. The hourly noise contour levels generated by the airport's departure and arrival operations were calculated, and the annoyed population was thus estimated considering a reference scenario, where only the residential area was taken into account, and also a dynamic one, in which the population's mobility was included. The results show that for the dynamic scenario, the total number of people annoyed by noise increases by 2.9%, while the number of highly annoyed people decreases by 10% compared to the reference scenario. On the individual level, there are many cases of both overestimating and underestimating the noise impact. Since so far the standard in airport noise mapping has been to use census data, we have shown the importance of including explicit population mobility in noise impact calculations.
SAE technical paper series, Mar 30, 2008
Journal of Transport Geography, 2023
HAL (Le Centre pour la Communication Scientifique Directe), Feb 25, 2020
The potential introduction of aircraft fitted with advanced counter-rotating open rotor (CROR) en... more The potential introduction of aircraft fitted with advanced counter-rotating open rotor (CROR) engine power plants should contribute significantly to the reduction of fuel burn and gaseous emissions. In the 1980s, prototypes of the first generation of open rotor engines were developed and tested. One of the findings was that the noise generated by these engines, even in the en-route flight phase, could be considered significant, thus hazarding public acceptance. Since then significant effort has been dedicated to improving the CROR aero-acoustic design; the new generation of CROR engines currently envisaged will be much quieter than its predecessors. The project was organised around 3 main challenges: 1. Adapt existing models for long-range propagation and validate them 2. Predict noise levels on ground generated by CROR en-route 3. Assess ground noise impact of CROR re. conventional powerplant This paper presents the main results of NINHA and gives recommendations for future work on CROR en-route noise.
Journal of the Acoustical Society of America, Apr 1, 2021
In 2018, NASA was the first to assess noise annoyance by low-sonic booms among a population not u... more In 2018, NASA was the first to assess noise annoyance by low-sonic booms among a population not used to hearing any of the acoustical phenomena associated with an aircraft flying at supersonic speeds (QSF18 study). Meanwhile, within the EU-project RUMBLE, data are collected, and literature reviewed used for research on community responses to low sonic boom demonstrator overflights. We present recommendations for such a field study, comprising NASA and RUMBLE studies' findings and other European efforts emphasizing items discussed by NASA and European researchers in the aftermaths of the first QSF18 results. We propose a study design for the CRLSB study in different European climate zones. A low-fidelity simulation model has been developed to pre-select test sites, supplemented by a more detailed impact model (NENA) for final site selection and preparation of the survey. We identified an approach of mixed survey modes, including experience-sampling procedures, as the most desirable modus operandi for community response assessment. Further, we propose a method for calculating desired sample sizes when applying linear mixed-effects modeling to data collected from a continental field study. [This project has received funding from the European Union's Horizon 2020 research and innovation program under Grant Agreement No. 769896.]
One of the objectives of Clean Sky GRC5 is to implement a tool for the minimisation of noise impa... more One of the objectives of Clean Sky GRC5 is to implement a tool for the minimisation of noise impact on the ground, capable of being executed on-board “on-the-fly”, providing flight directives to the Flight Management System of the helicopter. The semi-empirical model to be used for this purpose requires information to be derived from experimental data. For this purpose noise measurements have to be made simultaneously on the exterior of the helicopter (i.e. close to the noise source) and on the ground. The main objective of the ANCORA project was to develop the measurement systems and methodologies required to derive the transfer functions between on-board and ground-based microphones and validate them with flight tests. .
Applied Acoustics, 2016
Abstract The noise metric recognized as universal to describe aircraft flight noise events and co... more Abstract The noise metric recognized as universal to describe aircraft flight noise events and community noise pollution as a whole has not been yielded yet. Among a set of factors that impacts aircraft noise perception is a number of flights – number of aircraft noise events. This article deals with the number of flights’ influence on applicability of the usually used environmental noise metrics: equivalent Leq and maximum Lmax sound level for the long-term interval of their observation. The correlation between Leq and Lmax levels is considered against duration of observation interval. As a result the definition of representative duration is obtained. Noise measurements provided within representative time interval allow to assess the annually averaged value of equivalent sound level adequately. The adequacy or representativeness of measurements results is based on accuracy criterion taking into account the ‘noisiest’ events only for long-term Leq evaluation procedure under consideration. The long term noise descriptors are considered as the parameters of averaged ‘virtual’ flight noise event, for which the both Leq,avg and Lmax,avg are interrelated through averaged sound exposure energy for all events in observation. The results show that for airports with low intensity of flights (around 5 events per hour during the day) the long term equivalent sound level is heavily changing in relation with the long term maximum sound level, but for high intensity flight traffic this interrelation is quite stable. In the vicinity of airports with low flight intensity the maximum sound level as a noise impact metric is more sensitive than the equivalent level. Inside the areas, where the value of mandatory descriptors Lden (Ldn) is in conformity with established limits for environmental noise, proposed statistical post-processing analysis provides to recognize some additional reasons of community annoyances. The proposed in article assessment scheme was applied for data sets collected at the points of noise control closely to airports with low (about 30 flight noise events per day – Vilnius airport) and high (200–250 flight noise events per day – Madrid-Barajas airport) flight intensity.
Journal of Transport Geography
Sociedad Española de Acústica, 2008
Resumen En este trabajo se pretende validar el posicionamiento y la localización de aeronaves dur... more Resumen En este trabajo se pretende validar el posicionamiento y la localización de aeronaves durante las maniobras de aterrizaje y despegue, para ello se tienen en cuenta la metodología empleada en un trabajo previo donde se determinaron los parámetros geométricos y cinemáticos de la trayectoria de aeronaves a partir de los registros de niveles de presión sonora. La validación del método se lleva a cabo a partir de medidas " in situ " monitorizadas con un GPS diferencial en tiempo real, y su comparación con la información que extraemos de los registros sonoros realizados en un punto de tierra durante las citadas maniobras. Abstract This paper aims to validate the aircraft positioning and location during landing and take off maneuvers, the methodology used in a previous work is taken into account to identify the geometry and cinematic parameters of the path of aircraft from records sound pressure levels. The method validation is carried out from measures in situ with a real time differential GPS, and their comparison with results extracted from sound recordings obtained in a point of land during those maneuvers.
To support the monitoring activities required by the European Environmental Noise Directive (END)... more To support the monitoring activities required by the European Environmental Noise Directive (END) as well as ICAO noise standard setting, an adequate noise modelling capability is required that encompasses all types of aircraft, including rotorcraft. However, the international guidance to model aircraft noise such as ICAO Doc 9911 and ECAC Doc 29 is limited to fixed-wing aircraft, thus not covering rotorcraft. The interim approach in the Environmental Noise Directive (END) is to handle helicopters as a fixed-wing aircraft. Although this assumption has been considered to be acceptable when used at macroscopic level, it lacks in robustness when applied to the assessment of airport noise or other urban noise. A more robust modelling method, better accounting for the specific noise characteristics of helicopters, is therefore required.
This ANIMA Deliverable sets out to review available noise metrics and tools to help identify effe... more This ANIMA Deliverable sets out to review available noise metrics and tools to help identify effective and ineffective practice with the aim of informing the development of a Best Practice portal designed to assist airports to make the best use of noise modelling tools and their outputs. The review acknowledges the growth in the range of noise indicators now in use, often developed in an attempt to address specific stakeholder requirements. Whilst on the one hand the enhanced capability to 'capture' different aspects of the noise environment, on the other the picture can be seen as overly complex and confusing. In an attempt to provide some structure to the noise information now available and the modelling tools used to arrive at many of these outputs Sections 3 and 4 of this Deliverable develop frameworks for their categorisation. The Deliverable concludes that it is impossible to define best practice noise metrics on the basis of evidence from systematic assessments. Thus,...
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Papers by Nico van Oosten