Uncertainty Evaluation in Modelling of Acoustic Phenomena with Uncertain Parameters Using Interval Arithmetic

Uncertainty assessment in modelling of acoustic phenomena with uncertain parameters using interval arithmetic on the example of the reverberation time estimation, are presented in the paper. The application of the classical interval analysis formalism as well as its expansions are shown. Statistical methods of estimation of the reverberation time are based on parameters, which are related, among others, to the geometry of the analysed room, characteristics of sound absorption, and interior transmission. Values of these parameters are usually difficult to determine, which has a significant influence on the modelling result. The interval analysis allows to determine the variability interval of the parameter being estimated. The authors determined the influence of the input parameters uncertainty on the estimated reverberation time, calculated according to the Sabine, Eyring-Norris and Millington-Sette formulae. The uncertainty analysis was performed for the literature data, related to the reverberation time calculations of the room of a certified acoustics.