Optimization of Absorption Coefficients for Numerical Acoustic Simulation

  • Gandhi Mora Escuela Politécnica Nacional
  • José Lucio Escuela Politécnica Nacional
  • Luis Bravo Universidad de las Américas.
Keywords: Optimization of absorption coefficients, modified “hill-climbing”, acoustic computational simulation

Abstract

The following work presents a methodology to optimize the absorption coefficients, conventionally considered as the main input parameters of room acoustical simulators. In the first place a presentation of the main characteristics of the acoustic simulator is made. Next, the procedure that is based on a modified “hill-climbing” approach is detailed. It performs the optimization of the coefficients value in an iterative procedure, which includes the calculation of the acoustic quality parameters (AQPs) with the results of an acoustic simulation of a real room. The AQPs from each simulation are compared with experimental measurements performed in the room, used as a reference for iterative adjustments. Finally, the results of the last iteration show a substantial reduction of the error, showing differences of 5.83% with the AQPs measured in the real room.

DOI  

Downloads

Download data is not yet available.

References

I. Bork, “A comparison of room simulation software-the 2nd round robinon room acoustical computer simulation,”Acta Acustica united withAcustica, vol. 86, no. 6, pp. 943–956, 2000.

M. Vorl ̈ander,Auralization: fundamentals of acoustics, modelling, si-mulation, algorithms and acoustic virtual reality. Springer Science &Business Media, 2007.

ISO3382, “Measurement of the reverberation time of rooms with refe-rence to other acoustical parameters,”Acoustics, 1997.

J.-J. Embrechts, “Sound field distribution using randomly traced soundray techniques,”Acta Acustica united with Acustica, vol. 51, no. 6, pp.288–295, 1982.

S. Dance and B. Shield, “The complete image-source method for theprediction of sound distribution in non-diffuse enclosed spaces,”Journalof Sound and Vibration, vol. 201, no. 4, pp. 473–489, 1997.

U. M. Stephenson, “Quantized pyramidal beam tracing-a new algorithmfor room acoustics and noise immission prognosis,”Acta Acustica unitedwith Acustica, vol. 82, no. 3, pp. 517–525, 1996.

D. Alarc ̃ao, J. B. Coelho, and R. Tenenbaum, “On modelling of roomacoustics by a sound energy transition approach,” inProc. of EEAsymposium on architectural acoustics. Madrid. Citeseer, 2000.

H. Kuttruff,Room acoustics. Crc Press, 2009.

C. L. Christensen, G. Koutsouris, and J. H. Rindel, “Estimating absor-ption of materials to match room model against existing room using agenetic algorithm,”Proceedings of Fourm Acusticum, pp. 7–12, 2014.

Dalenb ̈ack,Datensatz der CATT-Software.Data-Category in CATT:BRICK PLASTERED, C: Walls, D: Plastered, 2000.

C. Harris,Noise Control in Buildings. McGraw Hill, 1994.

Harris,Handbook of Acoustical Measurements and Noise Control.McGraw Hill, 1991.

A. Pilch, “Optimization in the validation of the room acoustic model,”Proceedings of EuroRegio, 2016.

R. A. Tenenbaum, T. S. Camilo, J. C. B. Torres, and S. N. Gerges,“Hybrid method for numerical simulation of room acoustics with auralization: part 1-theoretical and numerical aspects,”Journal of the BrazilianSociety of Mechanical Sciences and Engineering, vol. 29, no. 2, pp. 211–221, 2007.

L. L. Beranek, “Acoustics,” 1996.

D. Alarc ̃ao, J. Bento Coelho, and R. Tenenbaum, “On modeling of roomacoustics by a sound energy transition approach,” inProceedings of EEASymposium on Architectural Acoustics, 2000.

P. Brunet Crosa, F. J. Santisteve Puyuelo, A. Vilanova, L. Chiarabini,G. Patow, E. Staffetti, and J. Suri ̃nach Caralt, “Estructuras geom ́etricasjer ́arquicas para la modelizaci ́on de escenas 3d,” 1999.

A. C. Isbert,Dise ̃no ac ́ustico de espacios arquitect ́onicos. Univ. Polit`ec.de Catalunya, 1998, vol. 4.

H. Haas, “The influence of a single echo on the audibility of speech,”J.Audio Eng. Soc, vol. 20, no. 2, pp. 146–159, 1972. [Online]. Available:http://www.aes.org/e-lib/browse.cfm?elib=2093

V. S. Gomez de Melo, “Inteligibilidade de salas de aula do ensinofundamental e avaliac ̧ao de qualidade ac ́ustica via respostas biauricularesobtidas com cabec ̧a artificial de dimensoes infantis,” Ph.D. dissertation,Universidade Federal do Rio de Janeiro, 2009.

M. R. Schroeder, “New method of measuring reverberation time,”TheJournal of the Acoustical Society of America, vol. 37, no. 3, pp. 409–412, 1965.

M. Abad Sorbet, “Estudio ac ́ustico y electroac ́ustico de la sa-la de conciertos ritmo y comp ́as (madrid),” Ph.D. dissertation,ETelecomunicacion, 2013.

R. A. Tenenbaum, T. S. Camilo, J. C. B. Torres, and L. T. Stutz, “Hybridmethod for numerical simulation of room acoustics: part 2-validationof the computational code raios 3,”Journal of the Brazilian Societyof Mechanical Sciences and Engineering, vol. 29, no. 2, pp. 222–231,2007.

S. P. Russell Norvig,Artificial intelligence a modern approach. St ́epha-ne Deconinck, 2010.

A. Gade, “Acoustics in halls for speech and music,” in Springer handbook of acoustics. Springer, 2007, pp. 301–350.

Published
2017-07-12
How to Cite
[1]
G. Mora, J. Lucio, and L. Bravo, “Optimization of Absorption Coefficients for Numerical Acoustic Simulation”, LAJC, vol. 4, no. 1, p. 13, Jul. 2017.
Section
Research Articles for the Regular Issue

Most read articles by the same author(s)