Modelling the thermal climate in city canyons

This paper presents an approach to the numerical modelling of the wind and thermal climates, as well as the energy budgets of city canyons. The model involves the coupling of three sub-models: (a) a surface energy budget model, (b) a windfield model, based on the k–ϵ turbulence model, and (c) a scalar dispersion model. In its current formulation, the model is two-dimensional, for clear sky conditions, for dry surfaces, and is most appropriate for conditions in which forced convection dominates over buoyancy effects. The model is capable of simulating the components of the wind; spatial patterns of canyon energy budget components; subsurface and air temperature; as controlled by location, date (i.e. solar path), weather conditions in the overlying air mass, canyon geometry and orientation, surface radiative and aerodynamic properties, substrate thermal properties, and, building interior climate.