Computer modeling of smog chamber data is discussed in three parts. First, a series of detailed chemical mechanisms were developed to describe the photochemical formation of ozone from nitrogen oxides and the following organic compounds (alone and in various combinations): formaldehyde, acetaldehyde, ethylene, propylene, butane, 1-butene, trans-2-butene, and 2,3-dimethylbutane. Second, a generalized kinetic scheme intended for use in models simulating the formation of ozone in urban atmospheres was refined. The generalized mechanism includes a condensed version of the detailed mechanisms developed in the first part plus a semi-empirical scheme to describe the oxidation of aromatic hydrocarbons. Third, the effects of smog chambers on ozone formation were examined. For this part of the study, similar experiments using nitrogen oxides and propylene in eight different smog chambers were simulated using the detailed propylene mechanism. The main chamber effects identified thus far are apparently due to nitrogen oxides degassing from the walls during experiments and differences between chambers in the spectral distribution of ultraviolet irradiation. Volume 2 contains graphs of measured and simulated pollutant concentrations for many smog chamber experiments.

"Contract No. 68-02-2428." "EPA-600/3-79-001b." "January 1979." "Project Officer Marcia C. Dodge."