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

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...

Improving Capabilities in Modeling Aircraft Noise Sources

Today's globalized world depends on civil air transportation, which has been continuously growing over the last decades. Nevertheless, the sustainability of this expansion is a challenge due to environmental problems. Along with greenhouse gas emissions, noise represents a severe hazard for human health, and consequently, noise regulations limit...

A multilevel optimization approach to route design and flight allocation taking aircraft sequence and separation constraints into account

This paper presents the development of a multilevel optimization framework for the design and selection of departure routes, and the distribution of aircraft movements among these routes, while taking the sequence and separation requirements for aircraft on runways and along selected routes into account. The main aim of the framework is to...

A multilevel optimization framework for aircraft operations on near-airport communities: Minimizing noise impact and fuel consumption

With a significant impact on the development of the global economy and society, air transport is predicted to rapidly grow in the coming years. Unfortunately, while delivering positive global economic and social benefits, air transport has also generated an adverse influence on the environment, especially on the quality of life of communities...

An optimization framework for route design and allocation of aircraft to multiple departure routes

In this article, we present the development of a two-step optimization framework to deal with the design and selection of aircraft departure routes and the allocation of flights among these routes. The aim of the framework is to minimize cumulative noise annoyance and fuel burn. In the first step of the framework, multi-objective trajectory...

Air traffic assignment based on daily population mobility to reduce aircraft noise effects and fuel consumption

The paper first investigates the influence of daily mobility of population on evaluation of aircraft noise effects. Then, a new air traffic assignment model that considers this activity is proposed. The main objective is to reduce the number of people affected by noise via lowering as much as possible the noise exposure level L <sub>den</sub...

Microphone arrays for imaging of aerospace noise sources

With the continuous growth in demand for air traffic and wind turbines, the noise emissions they generate are becoming an increasingly important issue. To reduce their noise levels, it is essential to obtain accurate information about all the sound sources present. Phased microphone arrays and acoustic imaging methods allow for the estimation of...

Sound transmission in and radiation from hard-walled annular ducts related to fan engine inlets

In this report the sound propagation in a hard-walled annular duct of finite length is investigated. The individual modal solutions so found are described. The main properties which are calculated in the present report, are the modal intensity and the modal far field directivity pattern. The modal intensity is determined by the rate of mode...

Calculation of acoustic modes in an infinite duct with shear flow and sound absorbing walls

The sound field in an infinitely long duct with shear flow and sound absorbing walls, but with the sound source unspecified, is analysed into its constituents, the acoustic duct modes. The equations, wave numbers, and various properties of the modes are discussed. Some calculated results are used to show the effects of shear flow and absorbing...