Record Details
Construction and evaluation of an airshed-episode model for air resource management
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Construction and evaluation of an airshed-episode model for air resource management |
| Names |
Reiquam, Howard Edward, 1931-
(creator) Lowry, W. P. (advisor) |
| Date Issued | 1968-11-07 (iso8601) |
| Note | Graduation date: 1969 |
| Abstract | A mathematical model of the atmosphere in an airshed is developed, which relates pollutant source distributions and intensities to the volume of air available for dispersion and to pollutant concentrations or air quality standards. It can be used as a tool for obtaining an answer to an air resource management question such as, "With a given air quality standard, what is the optimal distribution of sources which will minimize the likelihood that pollutant concentrations will exceed that standard in an airshed with a given climate?" In contrast to diffusion models which operate on plumes expanding under the influence of turbulent eddies, the airshed-episode model involves the transport and accumulation of pollutants within an entire airshed during types of episodes which are characteristically associated with maximum observed concentrations. An airshed is treated as a set of discrete sub-volumes and a basic assumption is that mechanisms exist which will, during the course of an episode, effect complete mixing resulting in a uniform distribution of pollutants within each sub-volume. By continuity considerations, it is possible to relate emissions within each volume to final concentrations everywhere in the airshed. The model can be applied "backward" using dynamic programming so as to optimize the allocation of emission rates in the various parts of an airshed in order that specified air quality standards not be violated. The airshed-episode model has been evaluated in the conventional configuration, in which it yields estimates of concentrations resulting from particular source distributions, using realistic source and meteorological data for the Willamette Valley of western Oregon. The calculated patterns of concentration are qualitatively quite similar to patterns observed in the valley during the annual period of field burning. In the inverse configuration, the model has been used to allocate optimal emission rates which would yield a uniform concentration everywhere in the airshed during episodes, and also to illustrate the optimal allocation of emission rates in an airshed with an "industrial area" superimposed upon an otherwise uniform air quality standard. The latter case illustrates the limitations, in the form of emission standards, which must be imposed on industrial zones in order that excessive emissions there not result in degradation of air quality far beyond their areal limits. |
| Genre | Thesis/Dissertation |
| Topic | Air -- Pollution |
| Identifier | http://hdl.handle.net/1957/45915 |
