HR: 1340h
AN: A33D-1560    [Abstracts]
TI: Comparison of a 13,500-Reaction Near-Explicit Chemical Mechanism With Smog Chamber Data and its Implementation Into a Fast Solver to Study the Ambient Sensitivity of E85 Versus Gasoline Emissions
AU: * Ginnebaugh, D
EM: moongdes@stanford.edu
AF: Stanford University, Civil and Environmental Engineering Environmental Fluid Mechanics Laboratory, Stanford, CA 94305-4020,
AU: Liang, J
EM: jliang@arb.ca.gov
AF: California Air Resources Board, P.O. Box 2815, Sacramento, CA 95812,
AU: Jacobson, M Z
EM: jacobson@stanford.edu
AF: Stanford University, Department of Civil and Environmental Engineering Terman Engineering Center M42, Stanford, CA 94305-4020,
AB: The study of urban, regional, and global air pollution requires the accurate and fast simulation of atmospheric chemistry, particularly for determining the composition of gases that condense to particulate matter. To date, atmospheric models that have solved chemistry in 3-D have been constrained by computer time, requiring chemical mechanisms used within them to be condensed. When chemicals are grouped within the mechanism, though, individual characteristics and accuracy are often lost. Here, the near-explicit Master Chemical Mechanism (MCM, version 3.1, LEEDS University) is implemented into the SMVGEAR II chemical ordinary differential solver to provide the speed necessary to simulate explicit chemistry in three dimensions. The MCM has over 13,500 organic reactions and 4,600 species. SMVGEAR II is a sparse-matrix vectorized Gear solver that reduces the computation time significantly while maintaining any specified accuracy. The near-explicit mechanism allows species to maintain their individual characteristics and improves the modeling of organic and inorganic chemicals in the atmosphere. This is important for simulating the gas-to-particle conversion of explicit chemicals. The model is used to compare the MCM treatment of alkene and aromatic chemistry with smog chamber data and another chemical mechanism. A test case for the air-pollution impacts of the tailpipe emissions from E85 is also performed. Potential impacts of ethanol are increasingly relevant today because of the increased use of ethanol in transportation fuels. The air pollution impacts of all fuels should be investigated before they are used widely.
DE: 0345 Pollution: urban and regional (0305, 0478, 4251)
DE: 0478 Pollution: urban, regional and global (0345, 4251)
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting