Experimental and numerical investigation of thermal plume in urban surface layer

A fundamental experiment was conducted to approximately demonstrate the subscale thermal plume over constructions in the urban surface layer. Furthermore, a new subscale modeling for the urban surface layer was proposed. The feasibility of the proposed model was discussed by comparing the two-dimensional numerical simulation results with the experimental one. The present study clarifies, for the first time, subscale thermal plumes with many tiny vortices produced over a simplified model of urban structures. These vortices occur in the thermally stable stratified air layer and strongly promote the ambient temperature rise. The numerical simulation showed a significant temperature increase of more than 5 degreesC in the region over the urban structures. Information and results collected from this research can be used for future practical applications in planning, redevelopment, and restructuring of urban cities. (C) 2003 Elsevier Inc. All rights reserved.