title: Energy-based method for near-real time modeling of sound field in complex urban environments.
abstract: Prediction of the sound field in large urban environments has been limited thus far by the heavy computational requirements of conventional numerical methods such as boundary element (BE) or finite-difference time-domain (FDTD) methods. Recently, a considerable amount of work has been devoted to developing energy-based methods for this application, and results have shown the potential to compete with conventional methods. However, these developments have been limited to two-dimensional (2-D) studies (along street axes), and no real description of the phenomena at issue has been exposed. Here the mathematical theory of diffusion is used to predict the sound field in 3-D complex urban environments. A 3-D diffusion equation is implemented by means of a simple finite-difference scheme and applied to two different types of urban configurations. This modeling approach is validated against FDTD and geometrical acoustic (GA) solutions, showing a good overall agreement. The role played by diffraction near buildings edges close to the source is discussed, and suggestions are made on the possibility to predict accurately the sound field in complex urban environments, in near real time simulations.
authors.affiliation: Department of Mechanical Engineering, Virginia Tech, Durham Hall, Blacksburg, Virginia 24061, USA. psteph7@vt.edu
authors.forename: Stephanie M
authors.initials: SM
authors.lastname: Pasareanu
authors.forename: Marcel C
authors.initials: MC
authors.lastname: Remillieux
authors.forename: Ricardo A
authors.initials: RA
authors.lastname: Burdisso
mesh_terms: D000042:Absorption; D000162:Acoustics; D002958:City Planning; D003198:Computer Simulation; D004058:Diffusion; D004781:Environmental Exposure; D005160:Facility Design and Construction; D005583:Fourier Analysis; D006801:Humans; D008962:Models, Theoretical; D009038:Motion; D009622:Noise; D009716:Numerical Analysis, Computer-Assisted; D011312:Pressure; D015203:Reproducibility of Results; D013016:Sound; D013997:Time Factors