Aircraft noise

About: Aircraft noise is a research topic. Over the lifetime, 3051 publications have been published within this topic receiving 32039 citations.

Active sound attenuation across a double wall structure

Abstract: The possibility of achieving significant local and global sound attenuation across a flat double wall is demonstrated. It is also shown that sound can be prevented from entering the interior of a cabinlike environment. The approach used is unlike established active noise control techniques.

The Number-of-Events as a Predictor Variable in Aircraft Noise Annoyance Models

Abstract: Aircraft noise may have a number of direct adverse effects on the communities surrounding airports, including annoyance. The annoyance reactions of individuals and communities to aircraft noise are predicted with annoyance models, which are normally functions of predictor variables that describe the noise exposure. The number of aircraft events that a person is exposed to (the number-of-events), has been hypothesized as a significant contributor to annoyance. However, most models of annoyance to aircraft noise are functions only of the average sound energy of the total noise exposure. The purpose of this research is to quantify the relative effects of sound level and number-of-events in historical noise survey data sets and to develop a survey simulation tool to help in the design of future surveys so that the collected data will be sufficient to compare the performance of proposed annoyance models. The models considered here are Day-Night Average Sound Level (DNL) and those that are a function of sound level and number-of-events. Seven historical data sets were collected and analyzed individually and in combination. Multiple linear regression models were estimated using the annoyance, sound level, and number-of-events variables in the data sets. The contributions of sound level and number-of-events to the prediction of annoyance were compared. Most regression models could not be distinguished from an equal-energy annoyance model. A general-purpose tool was developed to simulate annoyance surveys around airports. Monte Carlo simulations were performed to evaluate the effectiveness of survey sampling approaches. Annoyance surveys were simulated around three airports in the United States. The use of stratification, as opposed to simple random sampling, resulted in more robust estimation of annoyance models.

Landing Gear Noise Identification Using Phased Array with Experimental and Computational Data

Abstract: In regard to aircraft noise mitigation, this paper focuses on noise emission by a simplified nose landing gear (NLG), whose noise sources are identified by the means of sensor array methods. More precisely, following a former characterization of the aeroacoustics by the NLG via dedicated experiments and computations, the subsequent experimental and numerical noise signals are applied two popular sensor array methods of noise localization, namely, classical beam forming (CBF) and deconvolution approach for the mapping of acoustic sources (DAMAS). The resulting noise source maps are then analyzed from both the points of view of phenomenology (NLG noise generation mechanisms) and methodology (noise localization methods and application). The results show how sensor array methods (more especially DAMAS) are capable of revealing the underlying physics of the NLG noise source mechanisms, whether it is within an experimental or a computational context. This speaks in favor of a more systematic use of sensor array methods for investigating the noise physics of aircraft components.