Noise level prediction in a bakery using panel contribution analysis combined with scale modeling

Panel contribution analysis combined with scale modeling was utilized to determine the sound pressure level at different positions in a bakery. The primary sources of noise were three heating and air conditioning units. Each of the units was discretized into several patches and the volume velocity for each patch was measured. Transfer functions were measured between the patches and two different customer locations for the full-scale baseline case and using a 1/10 scale model. Transfer functions for the scale model were adjusted to account for air attenuation in the full-scale case. Panel contribution analysis was used to predict noise levels assuming both correlated and uncorrelated sources. Predicted results compared well with measurement. The suggested method can be used to assess the sound pressure levels in large interior spaces before they are constructed so long as the source positions are known. In addition, contributions from the individual sources can be assessed and ranked.