Comparative study of turbulence characteristics at different time intervals of surface boundary layer and super-high altitude typhoon field.

Based on the field measurement of surface boundary layer wind field during the passage of typhoon Kalmaegi, Fung-wong, Jangmi and Morakot, and the super-high altitude wind field during the passage of typhoon Fanabi, Megi and Lionrock, this paper conducted a comparative study of turbulence intensity at different time intervals (3 seconds, 1 minute, 10 minutes and 1 hour) of surface boundary layer and super-high altitude typhoon field, and analyzed the turbulence characteristics and its relationship with different time intervals of boundary layer typhoon field. The results clearly demonstrate that the mean wind speed and wind direction gradually stabilized with the increase of the time interval. 1 minute or 3 seconds time interval data reveals a good fluctuating and variations characteristics of mean wind speed and direction, turbulence intensity and gust factor, especially on larger wind speed occasion. There is great difference between the surface boundary layer and super-high altitude typhoon field in the aspects of mean wind speed discreteness and the ratios between the maximum mean wind speeds at different time intervals. The code empirical formula estimation recommended by the Architectural Institute of Japan (AIJRLB-2004) can be roughly utilized in the longitudinal turbulence intensity estimation of super-high altitude wind field in southeast China coast. The longitudinal turbulence intensity decreases more quickly than the lateral' turbulence intensity with the decrease of the time interval when the time interval is shorter than 10 minutes. The 3 seconds time interval turbulence intensity in longitudinal direction is smaller than the value in lateral direction lightly for the super-high altitude typhoon field. The 3 seconds time interval turbulence intensity in longitudinal direction is smaller than the value in lateral direction greatly for the surface boundary layer typhoon field. [ABSTRACT FROM AUTHOR]