第24回風工学シンポジウム
Dec 5 - Dec 7, 2016日本建築学会 建築会館ホール
第24回風工学シンポジウム
Dec 5 - Dec 7, 2016日本建築学会 建築会館ホール
[15]Measurement of Roughness Length in an Urban Area
○Tatsuki Hirano1, Hirofumi Sugawara2, Saya Araki1(1.Graduate School of Science and Engineering, National Defense Academy of Japan., 2.Department of Earth and Ocean Sciences, National Defense Academy of Japan.)
Keywords:
Roughness length,Urban canopy,Field observation
Roughness length was measured over the urban building canopy in Shibuya Tokyo. The study area includes low residential and highly built-up buildings. A sonic anemometer mounted in the tower at 52 m AGL measured turbulence, and the roughness length was determined by using the log profile equation and the measured wind speed. The measured roughness length agreed qualitatively with the land-cover type; 1.2 m for highly built-up area and 0.6 m for lower residential area. The parameterization for roughness length developed by Kanda et al. (2014, Boundary-Layer Meteorology) was validated with the measured results. Although some uncertainty remains for the footprint size, the parameterization agreed with the measurement.