Application of the Empirical Kinetic Modeling Approach to Urban Areas. Volume 3. Philadelphia

摘要

The Empirical Kinetic Modeling Approach (EKMA) was evaluated using the results of model applications in the Philadelphia area, primarily by comparing results of the box model (OZIPM) that forms the basis of the EKMA with those of more sophisticated models. The study was carried out at several levels, beginning with evaluation of OZIPM and ending with an evaluation of the control strategy predictions resulting from use of the EKMA isopleth methodology. OZIPM results were compared with those of the Urban Airshed Model (UAM), which is listed as one of the EPA's preferred models, and the Systems Applications Trajectory models, as well as with those obtained with modified versions of the original OZIPM model. The basic OZIPM model is a simple moving air parcel, or box, model that uses a detailed chemical mechanism for surrogate propylene and butane hydrocarbons. The model treats time-dependent precursor-emission factors and expansion of the air parcel. Entrainment is treated by assuming that constant concentrations exist outside the parcel. The primary emphasis of this comparison study was identification of features in the basic OZIPM model that could explain differences between the results of the OZIPM model and those of other models.