Abstract
The environmental impact of transport has become an important issue for legislators, industry, academic researchers and end-users. During the past decades, all these stakeholders were frequently confronted with the environmental impact of traffic: smog, acid rain, green house gasses and toxic particles. Reductions in pollution per vehicle mile have been offset by increased demand for industrial and recreational use in many parts of the world. When considering atmospheric pollution, policy makers base their decisions on models of traffic flows and estimates of the pollution caused.
Objectives
Currently a dynamic energy consumption and emission model is being developed by the DECADE-consortium under the Fifth Framework Programme of the European Commission. The DECADE simulation tool aims to predict vehicle fuel consumption and emissions for a given distance-speed profile. When this model is linked with existing traffic flow data and atmospheric dispersion models more accurate predictions of pollution levels can be obtained. Furthermore, policy makers are able to analyse in detail the effects of improvements in traffic flow control, vehicle technology and dispersion patterns. They are then better placed to set well founded strategies to influence traffic flow, traffic density, emission and fuel consumption levels or any useful combination.
Approach
The DECADE simulation model uses dynamic emission maps from powertrain measurements made on a test bench and specifically designed algorithms to incorporate the dynamic emissions due to transient vehicle operation in the model output. Vehicle measurements in controlled conditions and in real traffic are used to expand and validate the model. All test bench, vehicle and on-road measurements are performed with VOEM-Low, Vitos new on-board emission and fuel consumption measurement system. While being compact enough to fit into a small car, it is capable of dynamically and precisely measuring low emissions of vehicles complying with future emission standards like EURO IV or CARB Light Duty to become effective around 2005.
Expected results
The specific contribution of the DECADE simulation model for air pollution dispersion calculation is to provide the link between traffic models and dispersion models. By replacing averaged emissions factors with estimates calculated from real-world vehicle movements, more accurate, time and position resolved emission data is provided. Consequently the results of the dispersion models allow researchers to investigate more accurately the effects of increasing traffic as well as counteractions like measures affecting traffic flow or introduction of new emissions control technologies. This allows more effective actions to be taken to improve air quality.