Characterization of Transient Dispersion Processes in an Urban Environment
نویسندگان
چکیده
Validating LES-based flow and dispersion models for the purpose of predicting transient flow and dispersion phenomena is more demanding than validating RANS-based codes. Since the model output is no longer related to stationary or quasi-stationary boundary conditions, and since the model results are not restricted to mean flow and average dispersion patterns, an evaluation of the model based on mean results is no longer adequate. A more sophisticated but also more complex validation approach based on statistically representative ensembles is required. Reference data is needed which reliably identifies mean as well as extreme values of concentration, dosage and cloud travel times for a given dispersion scenario. An example of how systematic wind tunnel measurements can characterize transient dispersion processes of puffs in a complex urban environment is given.
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