Performance of a Gaussian Model for Centerline Concentrations in the Wake of Buildings

摘要

The inherent variability of 10- to 60-min average ground-level plume centerline concentrations in the wake of buildings and inherent limitations on the performance of a Gaussian plume model are presented. Point comparisons between observed and model predicted concentrations were evaluated for three sets of field measurements. The presentation is based on a quantitative evaluation of the same model that was qualitatively evaluated in another presentation. The same method prescribed for estimating enhanced dispersion in the wake of buildings and its incorporation into the Gaussian plume equation is used here. A sample of performance measures is judged to provide an adequate basis for determining the strengths and weaknesses of the model. For groups with reduced measures of mean error, the variability among errors was reduced to values between 50 and 100 percent of the mean concentration, which appears here to represent the inherent limitation of a simple Gaussian plume model.