ENVIRONMENTAL ENGINEERING STUDIES ON THE STRUCTURE OF NATURAL WIND IN URBAN AREA AND ITS EFFECTS ON BUILDINGS : Report No. 2, Properties of natural wind over the urban area-2 On the velocity fluctuations

Abstract

In this report No.2, the following problems are discussed. (1) The comparison of wind velocity and the direction on two places in Tokyo, Tokyo Tower and Tokyo District Meteorological Observatory, is descrbed in the section 3, and the results are shown in Fig. 3.2-3.3. (2) The observation on the turbulent velocity and the fluctuation on the air temperature was carried out by authors at Tokyo Tower from Feb. to Mar. in 1969. The results obtained are described in the section 4, the auto correlation function and the power spectrum density function on the velocity comporment along the mean stream are obtained at the height 104m from the ground. The forms of above spectrum over the urban area are complex on comparing with one the grass surface or the sand. The relation between the velocity fluctuation and the atmospheric stability over the urban area is not clear within the limits of this observations.