Rolling resistance, air resistance and emission modelling
VTI performs modelling calculations that shows how vehicle characteristics, driving behaviour, road surface type etc. may affects the energy consumption and emissions from road traffic and thereby the air quality.
VTI performs modelling of exhaust emissions, rolling resistance and air resistance for single vehicles or vehicle fleets with the VETO or PHEM model. It is also possible to use both models together.
The road surface characteristics and its effect on rolling resistance and fuel consumption can be modelled. It is also possible to model the effect of water or snow on the road surface, which affects rolling resistance and fuel consumption. Air resistance and its connection to fuel consumption can be modelled for different types of vehicles.
Emission modelling with the VETO or PHEM models include exhaust particles (PM10) and exhaust gases (NOx nitrogen oxides and hydrocarbons among others). The effect of vehicle characteristics such as different tyre types, engines (including electric engines) and motor maps can be evaluated. The models can also take dynamic effects into account, such as vehicle acceleration, breaking, gear shifting and uphill/downhill driving.
By using the NORTRIP model VTI can also perform modelling of non-exhaust emissions. Non-exhaust emission are particles created by road, tyre and brake wear from vehicle traffic but also salt and sand from winter cleaning activities. These constitute the largest part of particle emissions from road traffic and are calculated based on traffic and weather conditions for one or several roads.
Ongoing and recent projects:
- PHEM and rolling resistance: Pilot study
Development of the emission model PHEM with regards to rolling resistance.