Modelagem computacional para simulação de campo acústico de baixa frequência em salas

• Autor(a) principal: Pimentel, Ismael Andrade
• Data de Publicação: 2008
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/13783
• topic: Sound-waves - Simulation methods; Acoustics, Architectural - Simulation methods; Acoustics, Architectural - Parameter estimation; Sound - Transmission - Simulation methods; Modal acoustics; Parameters acoustic; Ondas sonoras Métodos de simulação; Acústica arquitetônica Métodos de simulação; Acústica arquitetônica Estimativa de parâmetro; Som Transmissão Métodos de simulação; Acústica modal; Parâmetros acústicos; CNPQ::CIENCIAS EXATAS E DA TERRA::FISICA::AREAS CLASSICAS DE FENOMENOLOGIA E SUAS APLICACOES::ACUSTICA

This article discusses the numerical modeling of the propagation of sound waves in rooms, from the assessment of the field of sound pressure quadratic in the room. This research presents a computational model, based on modal approach of rooms with rectangular geometry, which improves the performance of the program for numerical simulation of acoustics of rooms RAIOS 3 for low frequencies. Initially, there was a theoretical and experimental modal analysis of a rectangular room for non-rigid and rigid walls, where an estimated sound pressure of all modes as a function of place and time. For this, is determining of the wavenumbers and frequencies of each mode, namely the eigenvalues and eigenfrequencies. The performance of the model is assessed from results with a rec tangular room and validated using measurement data of the PTB (Physikalisch-Technische Bundesanstalt), Germany, an inter-comparison named Round Robin 3, phase - 3. The main results were obtained by calculating the following parameters: reverberation time, (T30), clarity factor, (C80), difinition, (D50) and early decay time.