Experimental study of the wind flow in a coastal region of Japan

Wind flow over complex and steep terrain was investigated by a wind tunnel experiment and a numerical simulation. The mean value and the turbulence of the wind flow over complex terrain in a coastal region of Japan were measured by split-fiber and X-wire probes. It was found that the split-fiber probe can give a reasonable accuracy while the conventional X-wire probe measurement contains a large error because of the existence of reverse flow and strong across wind in complex terrain. The applicability of the power law to the wind prediction over complex terrain was also examined. It was noticed that the application of the power law for the estimation of the wind speed or the turbulence intensity in complex terrain is difficult. Numerical simulations were carried out by the non-linear model developed by the authors and the conventional linear model. The wind field predicted by the non-linear model shows fairly good agreement with the experiment while conventional linear model tends to overestimate the mean wind speed and underestimate the turbulence.