1. A study of pollutant concentration variability in an urban street under low wind speedsAdrian Dobre, Graham Nickless, Iain R White, Catheryn S Price, Damien Martin, Dudley E Shallcross, 2008, izvirni znanstveni članek Opis: The short time‐scale variability in pollutant concentrations in an urban street under very low wind speed conditions and short source–receptor distance has been investigated using the inert tracer sulfur hexafluoride (SF6) as a continuous point‐source (release times ≥ 5 min), and fast detection using separation by gas chromatography coupled with a μ‐electron capture detector (ECD). The results are complex but can be broadly interpreted in terms of horizontal wind speed and direction coherence. Comparisons with a simple dispersion model suggest that observed time‐averaged maximum concentrations approach predicted values, whilst instantaneous maximum concentrations vary greatly and would therefore be difficult to predict.
Najdeno v: osebi
Ključne besede: dispersion, tracer, intermittency
Objavljeno: 17.07.2019; Ogledov: 2331; Prenosov: 104
 Polno besedilo (289,67 KB) |
2. Short-range urban dispersion experiments using fixed and moving sourcesStephen E Belcher, Alison S Tomlin, James Tate, Marina K Neophytou, Rex E Britter, Fredrik Petterson, Iain R White, Graham Nickless, Catheryn S Price, Damien Martin, Dudley E. Shallcross, Janet F Barlow, Alan Robins, 2009, izvirni znanstveni članek Opis: Four perfluorocarbon tracer dispersion experiments were carried out in central London, United Kingdom in 2004. These experiments were supplementary to the dispersion of air pollution and penetration into the local environment (DAPPLE) campaign and consisted of ground level releases, roof level releases and mobile releases; the latter are believed to be the first such experiments to be undertaken. A detailed description of the experiments including release, sampling, analysis and wind observations is given. The characteristics of dispersion from the fixed and mobile sources are discussed and contrasted, in particular, the decay in concentration levels away from the source location and the additional variability that results from the non-uniformity of vehicle speed.
Najdeno v: osebi
Ključne besede: dapple, perfluorocarbon, tracer, mobile source
Objavljeno: 18.07.2019; Ogledov: 2195; Prenosov: 0
Polno besedilo (265,68 KB) |
3. Urban tracer dispersion experiments during the second DAPPLE field campaign in London 2004Damien Martin, Catheryn S Price, Iain R White, Graham Nickless, K Fredrik Petersson, Rex E Britter, Alan G Robins, Stephen E Belcher, Janet F Barlow, Marie Neophytou, Samantha J Arnold, Alan S Tomlin, Robert J Smalley, Dudley E. Shallcross, 2010, izvirni znanstveni članek Opis: As part of the DAPPLE programme two large scale urban tracer experiments using multiple simultaneous releases of cyclic perfluoroalkanes from fixed location point sources was performed. The receptor concentrations along with relevant meteorological parameters measured are compared with a three screening dispersion models in order to best predict the decay of pollution sources with respect to distance. It is shown here that the simple dispersion models tested here can provide a reasonable upper bound estimate of the maximum concentrations measured with an empirical model derived from field observations and wind tunnel studies providing the best estimate. An indoor receptor was also used to assess indoor concentrations and their pertinence to commonly used evacuation procedures.
Najdeno v: osebi
Ključne besede: Dapple, dispersion
Objavljeno: 18.07.2019; Ogledov: 2087; Prenosov: 0
Polno besedilo (1,69 MB) |
