Development of 3-D Ultrasonic Anemometer With Nonorthogonal Geometry for the Determination of High-Intensity Winds

The wind speed is an important quantity in various areas of knowledge. Among the existing types of anemometers, the ultrasonic is the one that requires less maintenance and may be used in most applications. This paper presents the development of an ultrasonic anemometer that measures wind speed in three dimensions. It discusses the important aspects of the mechanical structure of the equipment in order to minimize its influence in measurements. It also presents the electronic circuits used in the excitement and in the conditioning of signals of the transducers that make up the instrument. The equipment was calibrated in a wind tunnel, with a coefficient of determination R
²
= 0.999994, in relation to the reference method. In addition, results of field tests comparing two different mechanical structures are presented. Empirically, it is shown that a nonorthogonal arrangement for the anemometer favors the accuracy of the measurements. The results showed that the proposed equipment has an excellent accuracy for the measurement of up to 160 km/h.