Field investigation on heat transfer in an urban canyon

Field measurements of the heat transfer in an urban canyon running from east to west were performed both in summer and winter as a preliminary investigation of the heat transfer in an urban surface boundary layer. The canyon consisted of concrete buildings (16 m in height) with windows, standing face to face with an asphalt road (17 m in width) between them. The heat transfer in the urban canyon is represented by an energy balance at an imaginary surface called 'the top surface,' which is a plane positioned above the canyon at the same level as the roof surface. The net amount of the heat transferred into the urban canyon was more than four times larger than that into the roof and reached about 50 percent of the net radiation heat transfer on a summer day regardless of the meterological conditions. In the daytime, there was no significant difference in the convective heat transfer between the roof surface and the top surface.