Ultrasonic Anemometer

The Port of Riva Trajan He has set today the new ultrasonic anemometer which allows measurements to be made with a very high degree of accuracy. The data is already visible on App and on the website web

How does an ultrasonic anemometer

Wind speed and direction are determined by measuring the time taken by ultra-sonic pulses to accomplish the path from the transducer that generates the pulse to the transducer that receives.

The tool uses 2 of transducers pairs, oriented along two orthogonal axes. The detection of the wind speed along the two axes allows to determine, in addition to the intensity, also the di-rection of the wind.

The instrument measures the ultrasonic pulse travel time between the two transducers of the same pair in both directions. We define tA (Round Trip Time) e tR (time from returns-no) the travel times in the two opposite directions. If the wind speed is zero, tA and tR are equal.

In the presence of wind, one of the two times is greater than the other, and the comparison between the two times makes it possible to determine in which direction the wind is blowing and with what intensity. The measurement of the traveling time in both directions is used to cancel the dependency of the transmission speed of ultrasound in the air by the environmental conditions of temperature-ra, humidity and atmospheric pressure

explanatory diagram of the measurement
Sensor characteristics