Towards a model for electric vehicle noise emission in the European prediction method CNOSSOS-EU

• The CNOSSOS-EU model specifies the average noise emission from road vehicles.
• The light vehicle model, adapted to conventional vehicles, is incorrect for EVs.
• Transitional correction terms are proposed for the EV propulsion noise component.
• The rolling noise component is adapted to the low rolling resistance tyre subset.

The CNOSSOS-EU method is recommended in Europe for environmental noise prediction. In regards to road traffic, it includes vehicle noise emission models implicitly referring to internal combustion vehicles. The development of electrically driven vehicles calls for the future consideration of these vehicles in prediction models. On the basis of experimental data, the study reported in this paper proposes a noise emission model for extending CNOSSOS-EU to light electric vehicles. Correction terms to be applied to the propulsion noise component are determined. Investigations on a sample of tyres with good rolling resistance performance, which is a main tyre selection criterion on these vehicles, indicated that no correction is required for the rolling noise component. Differences between the noise emission from conventional vehicles and electric vehicles are discussed for several road surfaces. Owing to the limited vehicle sample as well as transitional statements, this new model for electric vehicles running at constant speed over 20 km/h should be considered as a first step towards the definition of this vehicle technology in CNOSSOS-EU.