Accéder directement au contenu Accéder directement à la navigation
Communication dans un congrès

Estimating long-term microclimatic conditions for long-range sound propagation studies

Abstract : Sound propagation in the lower atmosphere strongly depends on the wind direction and the vertical gradients in the speed of sound. The latter depends in turn on the vertical gradients of wind velocity and temperature. Because of the natural space and time fluctuations in microclimatic conditions, the acoustic level at a large distance from the source must be considered as a random variable. Therefore, knowing the statistical characteristics of the fluctuations in microclimatic conditions is of great importance for estimating the accuracy of a measurement or a calculation of long-range acoustic levels. We describe a method based on a heat and mass transfer simulation model, for estimating hourly variations in local wind and temperature profiles. Two types of inputs are required: - site descriptors (soil and vegetation parameters acting on the surface energy and water balances: albedo, roughness length, soil type...); - standard climatic data provided by the meteorological network (insolation, wind velocity and direction, air temperature and humidity, precipitation...). Using long-term (i.e., several years) climatic data files, it is possible to calculate statistical distributions of the vertical wind and temperature gradients at some height above the surface, as well as the distribution of the vertical sound velocity gradient. For a given source-receiver configuration, the corresponding distribution function of sound levels can then be deduced. The method is illustrated by a case study perfomed with a 30 year climatic file for a typical rural site in France. As an example, we calculated the fraction of time during which the sound level exceeded a prescribed threshold, for one particular source-receiver configuration.
Type de document :
Communication dans un congrès
Liste complète des métadonnées

https://hal.inrae.fr/hal-02766294
Déposant : Migration Prodinra <>
Soumis le : jeudi 4 juin 2020 - 09:03:22
Dernière modification le : vendredi 12 juin 2020 - 10:43:26

Fichier

Brunet-Lyon-1996_1.pdf
Fichiers éditeurs autorisés sur une archive ouverte

Identifiants

  • HAL Id : hal-02766294, version 1
  • PRODINRA : 132888

Collections

Citation

Yves Brunet, Jean-Pierre Lagouarde, Vadim Zouboff. Estimating long-term microclimatic conditions for long-range sound propagation studies. 7. International Symposium on Long Range Sound Propagation, Jul 1996, Ecully, France. ⟨hal-02766294⟩

Partager

Métriques

Consultations de la notice

6

Téléchargements de fichiers

11