User's Guide for MPTER, A Multiple Point Gaussian Dispersion Algorithm with Optional Terrain Adjustment

摘要

The information presented in this user's guide is directed to air pollution scientists interested in applying air quality simulation models. MPTER is the designation for Multiple Point source algorithm with TERrain adjustments. This algorithm is useful for estimating air quality concentrations of relatively nonreactive pollutants; hourly estimates are made using the Gaussian steady-state model. The algorithm is most applicable for source-receptor distances less than 10 km and for locations with level or rolling terrain where a single wind vector for each hour adequately approximates the flow over the source and receptor sites. The terrain adjustment option is limited in application to receptors whose elevation is no higher than the lowest stack top elevation of the sources considered. Calculations are performed on the hourly meteorological data that the model requires: wind direction, wind speed, temperature, stability class, and mixing height. Emission information required of the point sources are source coordinates, emission rate, physical height stack diameter, stack gas exit velocity, and stack gas temperature. In addition to terrain adjustment, options are available for stack downwash, gradual plume rise, and buoyancy-induced dispersion. All printed output is optionally available so the user can avoid unneeded output volume. General information is contained in the Executive Summary and the first three chapters. The technical basis for the algorithm is given in Chapter 4 and Appendices A and B. The remaining material herein relates to use and understanding of the computer program for the algorithm.