We have been busy adding features to NoiseMap five over the last 12 months, particularly in relation to high speed rail.
NoiseMap 5.3.0 Beta 4 is now available to clients on a limited basis.
If your maintenance is current, then you may download a copy of this now – please contact us with your licence (dongle) number and we will direct you to the download page. If maintenance is not current, then please contact us for a quotation to update it. The cost remains unchanged at present
The main new features are:
- Users can specify the attenuation curves for noise barriers for each noise source on the railway vehicle. This can take into account differences in source spectra and absorption characteristics of the barrier. Any number of different curves can be specified.
- Pantographs (power collectors on top of the train) are directional sources which change with speed. This can particularly affect the Lmax values. Users can now specify the directivity and attenuation rate of pantograph noise.
NoiseMap assesses the effect of multiple diffracting edges (i.e. multiple barriers between the source and the receiver) using a procedure that combines the two most effective single barriers by taking into account their separation distance. This is similar to, but not identical with, the procedure stated in ISO 9613. However, the ISO does not state how to deal with the issue of many barriers between the source and receiver. The CNOSSOS-EU procedure assumes that the propagation path is in the form of a ‘convex hull’ over the tops of all the barriers, and then uses the path difference between the convex hull and the direct ray, although this procedure does not deal with the effect of differing barrier absorption. Work on resolving the issues and implementing a new procedure for multiple diffraction is being implemented. It is expected that a Beta version incorporating this additional feature will be released soon.
We have implemented a number of changes that improve the efficiency and speed of the calculation process.