Variability in the Short-Range Dispersion of Passive, Short-Duration Emissions

0549700 - ÚT 2023 GB eng J - Článek v odborném periodiku
Robins, A. - Hayden, P. - Gallacher, D. - Pace, S. - Chaloupecká, Hana
Variability in the Short-Range Dispersion of Passive, Short-Duration Emissions.
Archives in Biomedical Engineering & Biotechnology. Roč. 4, č. 2 (2021). E-ISSN 2687-8100
Institucionální podpora: RVO:61388998
Klíčová slova: boundary layer * dosage * mean * short-range dispersion
Obor OECD: Meteorology and atmospheric sciences
https://irispublishers.com/abba/pdf/ABBA.MS.ID.000584.pdf

The objective of this analysis was to use wind tunnel concentration measurements to describe the structure of dispersing clouds from an
elevated source in a deep turbulent boundary layer and to develop scaling rules that reduce the results to a universal form. The experiments were
carried out in a 1 m deep simulated atmospheric boundary layer in the EnFlo meteorological wind tunnel at the University of Surrey. Ensembles of
between 100 and 200 repeat emissions were used, with emission durations between 0.067 and 1.02 s with the reference flow speed at the boundary
edge of 2 ms-1. The fetch studied extended to about six source heights downwind (roughly, two boundary layer depths). The structure of the evolving
clouds was analysed to determine time of flight, along-wind spread and dosage and to compare the dosage behaviour with the concentration field in
a plume from the same source. This illustrated how the two were related and therefore how cloud dosage statistics (mean and standard deviation)
could be derived from plume data. It also demonstrated that much larger ensembles were required to reduce the statistical uncertainty in the mean
cloud properties. Consequently, the proof of the near-universal scaling presented is somewhat compromised. However, it is believed to be both
relatively simple and adequate for practical applications. An application to a sequence of short- term releases at full-scale is demonstrated. The next
steps involve testing these conclusions in a wider range of flow and dispersion conditions, namely in the presence of obstacles or complex urban
areas
Trvalý link: https://hdl.handle.net/11104/0340021