VERIFICATION OF THE JCAP ROADSIDE AIR QUALITY SIMULATION MODEL

By the reinforcement of the vehicle emission reduction requirement, NOX concentration in a roadside atmosphere reduced clearly recently. However, the ambient NO2 concentration does not show a variation. For the purpose of provision of data contributing to environmental policy making through development of high accuracy Air Quality Model and impact prediction of improved air quality, the Japan Clean Air Program had started. A commercial CFD model of Star-CD was used as the roadside air quality model. The chemical reactions of NO oxidation with ozone, photodissociation of NO2, and ozone formation are going to introduce in this model. Involving a spatial distribution of ozone concentration measurement, temporal and spatial variation of NO and NO2 was measured by the devices of chemiluminescence method which were prepared by each chemical species. Concentration-change was measured at the same time in four sites every one second to pay attention to a percentage of NO2/NOX which varied from route neighborhood to lee side way. The air flow of each sites were monitored by the ultrasonic 3D anemometer. The effect of NO2 concentration change due to the air stagnation or background ozone concentration was evaluated