The mathematical model that the software uses provides options to model noise emissions from a wide range of sources that might be present at industrial areas and urban areas. The basis of the model is the linear sound propagation  equation, which is used to model simple point source emissions from vehicles, industries, aircrafts,… Emission sources are categorized into two basic types of sources: point sources and line sources. The algorithms used to model each of these source types are described in detail in the following sections. The CUSTIC software accepts meteorological data records to define the conditions for sound propagation. The model estimates the noise level for each source and receptor combination and calculates user-selected averages.

For an external source, the noise level equation is 

Leq=LW-20Log(r)-11dB(A)

where r is the distance and LW the source power. However, for an industrial complex, the next equation will be used:

Leq=Li+10Log(S)-20Log(r)-14dB(A)

where S is the external surface and Li is the internal noise power.

Noise pollution map (colour gradient) in decibels dB(A) produced by roads. We have 1000 vehicles per hour at a velocity of 50km/h. The red colour represents high noise levels. 

Algorithms I - Algorithms II

Environmental software · environmental software solutions