[AAS06-P06] Wind speed estimation by low-cost visibility meter network
Keywords:Blowing snow, Disaster Prevention, Instrument Development
In regard to wind speed, which is essential in order to predict poor-visibility caused by blowing snow, conventional propeller-type anemometer has been used up to now. However, such propeller anemometer has moving parts so that the low-cost type lacks durability. On the other hand, the hot-wire and thermocouple type anemometer needs relatively high-power consumption. In this study we developed a new methodology for wind speed measurement using densely placed visibility meters, making use of the time difference between the snow particle passing at different apparatus. Experiments were performed using a wind tunnel at Cryospheric Environment Simulator of the Shinjo Branch (Snow and Ice Research Center, National Research Institute for Earth Science and Disaster Resilience). The three units of the visibility meter were set at an interval of 4-5 m in the wind tunnel and connected with a computer for data collections by wireless communication. The time interval of data sampling was set to 0.5 s. The propeller type anemometer to measure the wind speed as a reference was set downstream of the three observation units. The wind speed can be measured by detecting the delay time for snow particles to move from one unit to the next one. The wind speed obtained by our system was 8.8 m s-1, being averaged for data obtained at three points, while the wind speed measured by the anemometer was 9.1 m s-1. These results mean only with this poor-visibility meter network we can estimate the wind velocity with an accuracy of 3 percent.