Modal analysis of vehicle emission factors Facteurs dʹémission modaux des véhicules

This study reports on the analysis of emissions from light-duty vehicles conducted using a modal approach, which describes emissions for every single mode typical of traffic regimes (idle, constant speed, acceleration, deceleration). Base emission data were obtained from the chassis dynamometer with four driving cycles, developed with an appropriate on-road measurement campaign were performed in the Milan urban area. These were subdivided into acceleration ranges and analysed in terms of their dependence on speed, deriving relationships between emissions, speed and acceleration for pollutants typical of the traffic source (CO, VOC, NOx).