Technical note: Dispersion of cooking-generated aerosols from an urban street canyon

Abstract. The dispersion of cooking-generated aerosols from an urban street canyon is examined with building-resolving computational fluid dynamics (CFD). Using a comprehensive CFD model (PALM) sectional aerosol module (SALSA), emissions deep-frying and boiling are considered for near-ground elevated sources. With representative choices the source flux, inclusion dynamic processes decreases mean canyon-averaged number concentration by 15 %–40 % cooking emissions, whereas effect significantly weaker traffic-generated aerosols. effects deposition coagulation comparable boiling, but dominates deep-frying. Deposition maximised inside leeward corner vortices, while increases away source. characteristic timescales invoked to explain spatial structure coagulation. In particular, relative difference between concentrations simulations without strongly correlated ageing particles along trajectories or tracer age. It argued that, specific emission spectrum, qualitative nature within canopies determined ratio relevant dynamical timescale (e.g. age air).