Micrometeorology Measurement by Acoustic Method

In this paper, we describe a visualization method of wind velocity and direction distributions for micrometeorology measurement. The wind velocity and direction were measured in a noncontact mode within a measurement area using acoustic probes, on the basis of differences of the time of flight of sound. To reconstruct a two-dimensional distribution, eight acoustic transducers were installed at equal intervals along the circumference of a turntable. The reliability of the system was tested in a wind tunnel. The test was performed for two patterns: increasing wind velocity under a constant wind direction, and rotating wind direction under a constant wind velocity. For the two experimental patterns, two-dimensional distributions of the wind velocity and direction could be reconstructed. Compared with a reference measured with an ultrasonic anemometer, our results showed good agreement.