A numerical model for the simulation of the thermal processes inside the urban canopy layer is proposed. The model is coupled with a turbulence closure model for the atmospheric boundary layer with the purpose of analyzing the thermal effects of urban areas. In the model, the buildings and land uses inside each computational grid mesh are averaged by a lumping space-averaging method. Then, a model for the evaluation of momentum loss and heat exchange between the air and the urban canopy is developed. This model accounts for all processes which can generate heat inside the canopy layer such as the heating of wall, roof and the ground surface, the conduction of heat to buildings through windows, wall and roof, and the discharge of artificial heat due to air conditioners. The coupled numerical model was applied for the analysis of heating characteristics of a housing area and an office area and the influence of a housing area on the thermal climate of surrounding vegetative areas.
