Fabrication of four-path remote outdoor wind velocity measurement system and its performance evaluation

Abstract

A method is proposed for the remote measurement of the outdoor ground-surface two-dimensional (2D) vector wind velocity field averaged over a region of 10–50 m size. To this end, four-channel (4ch) sound wave transmitters and receivers were placed at the corners of a rectangular monitoring site. From the four-path travel time data, the wind velocity and direction averaged over the region were estimated under the uniform-wind-field assumption. By this method, misestimation due to the local turbulence wind field, which is encountered in conventional in situ-type anemometers, can be avoided. To achieve a satisfying speed data collection that keeps up with the rapid changes in real wind field, coded modulation signals were transmitted and received simultaneously between all the 4ch speaker/microphone pairs. Test experiments demonstrated that time variations of vector wind velocities spatially averaged over the area were successively measured with satisfying speed and accuracy.