Experimental Determination of Heat Transfer Resistance in Urban Canyon Environments

Abstract

The heat transfer resistance between a building canyon and the overlaying atmospheric boundary layer was evaluated in a long-term field observation. The recorded case is of a courtyard canyon of a university campus. The canyon has an aspect ratio of 0.22 and height of 13 m. The resulting resistance was observed to be clearly dependent on the wind speed and atmospheric stability in the range of 1.6 to 20 m^-1s. The random error in the measurement of resistance was estimated to be 27%; however, this does not nullify the above findings. The adequate lower-level reference temperature for the transfer parameterization was found to be the average for the entire canyon volume. This is because vortex-type airflow controls the heat transfer.