Numerical Model

Emission Numerical Model

Road traffic emission model

The emission model of the implemented road traffic is the CNOSSOS-EU model.

User can choose coefficients from the Directive 2015/996 and its amendment 2019/1010.

Rail traffic emission model

The emission model of the implemented rail traffic is the CNOSSOS-EU model.

Only french database, from SNCF, is implemented.

Without emission model

User can also add directly its own emission sound power level (LW).

Path finding algorithm

The path finding algorithm is a rubber-band like algorithm as specified in CNOSSOS-EU.

To optimize the processing time, this algorithm is taking benefit from a R-Tree spatial partioning algorithm.

Warning

Rays backwards to the source or receiver are not taken into account. For example, if a receiver is located inside a U-shaped building, only diffractions on horizontal edges will be taken into account.

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Propagation Numerical Model

The propagation model is the CNOSSOS-EU one.