Large industrial hall with non-uniform absorption, 3 fitting zones and 30 workplace (i.e. 30 receivers)

Description

Very large industrial hall (107m x 42m x 5m) with non-uniform absorption, multiple sound sources (5 configurations: 1 (C1), 12 (C2), 22 (C3), 7 (C4) and 30 (C5) sound sources), 30 receivers. This simulation includes 3 fitting zones, with the same diffusion properties.

All elements of this simulation are licensed under Licence Creative Commons Attribution 4.0 International License.

What is tested?

Comparison between SPPS and experimental data from [Ondet, 1988]. Additional information concerning the experimentation are given in [Ondet, 1984].

[Ondet, 1988] A.M. Ondet, J.L. Barbry, Sound propagation in fitted rooms—comparison of different models, Journal of Sound and Vibration, Volume 125, Issue 1, 1988, Pages 137-149, ISSN 0022-460X, http://dx.doi.org/10.1016/0022-460X

[Ondet, 1984] A.M. Ondet, J.L. Barbry, Prediction of noise levels in fitted rooms. Note Scientifique et Technique No. 52, INRS October 1984 (1984) (in French)

CAUTION - The following results present comparisons between numerical simulations carried out with I-Simpa and 'reference' data available in the scientific literature. However, it is difficult to prejudge the concept of 'reference'. The deviation between the simulations and the reference data that can be observed do not necessarily call into question the corresponding simulations but can also be associated with other sources of deviation (modeling assumptions, numerical instabilities, experimental uncertainties, etc.). In addition, some numerical models (like SPPS), based on random methods, may produce small deviations between two distinct simulations.

Results

Sound pressure level (configuration C1)

For all the 5 configurations (C1 to C5), the figures of the sound pressure level at the 30 receivers show a similar behavior between the SPPS results and the experimental data. However, we observe a "systematic" offset around 3-4 dB (overestimation of SPPS) with the reference data. Because, all results are given in absolute sound level (i.e. considering the sound power level of each source given in the reference article), one can assume a strong estimation of the source power of each source.

Sound pressure level (configuration C2)

Sound pressure level (configuration C3)

Sound pressure level (configuration C4)

Sound pressure level (configuration C5)

Calculation parameters

ParametersValue
Active calculation of Atmospheric absorptionYES
Active calculation of diffusion by fitting objectsYES
Active calculation of direct field onlyNO
Active calculation of transmissionNO
Calculation methodEnergetic
Limit value of the particle extinction5.0
Number of sound particles per source1 000 000 (C1), 100 00 (C2, C3, C5), 300000 (C4)
Number of sound particles per source (display)0
Random initialization number0
Receiver radius0.31
Simulation length (s)3.00
Time step (s)0.005