Characteristics of wind (1)

[5] VALIDATION OF OFFSHORE WIND OBSERVATION BY A DOPPLER- LIDAR MOUNTED ON A SIMPLE FLOAT IN THE NOHIRO PORT, AKITA PREFECTURE

○Satoru Goto¹, Kiyotoshi Otsuka¹, Hdero Hayashi² (1.Technical Research Institute, OBAYASHI Corp., 2.OBAYASHI Corp.)

Keywords:Wind observation, Off shore, Dopplar lidar, Simple floating unit

A low cost, floating offshore wind measuring system was developed, which is composed of a simple rectangular moored float on which a Doppler Lidar of having motion compensation function is mounted. Wind measurements using this system were carried out at Noshiro port, Akita prefecture, for the period of one year. Observed wind data were compared with those by meteorological mast built on the neighboring breakwater. Comparisons between the 10-minute mean lidar and met-mast winds show good agreement with each other, irrespective of acquisition rates or magnitudes of rolling and pitching motion of the float no larger than 10 degrees. Characteristics of the lider-observed vertical wind profiles were investigated through power-law fitting. The values of exponents tend generally to converge as wind speed increases. The exponents of the power-law wind profiles take the values slightly smaller than that of roughness class I surface of AIJ recommendation for the winds coming from the ocean.