Development of a measurement box to measure the 3D wind speed in an urban environment

Abstract

The present work aims to build a low-cost three-dimensional anemometer to measure the wind speed and direction in an urban environment. To begin with, some research on basic principles in scientific literature and also in patent database was done. Secondly, a market study was carried out and two propeller anemometers were purchased. A hi-tech ultrasonic sensor was also purchased to gather accurate measurements and to serve as input for the calibration of the low-cost anemometer. The propeller anemometers were then calibrated in a wind tunnel and some unexpected measuring errors became visible. Their accuracy was not as high as it had been anticipated in the datasheets. This resulted in a collaboration with the manufacturers to test and improve their products. Some more tests were carried out and concluded with great results. Then, the three-dimensional sensor was assembled using the two propeller anemometers and it was subsequently cross-checked with an ultrasonic anemometer in a roof of the Erasmushogeschool Brussel. Finally, a program was created to collect the data from the ultrasonic sensor and store the information in a file. To sum up, this project meets all the desired goals: it works autonomously, collects the data, and is movable. In addition, some other technical statements were concluded: at low wind speeds, the propeller anemometers also had a low resolution and measurements corresponding to the horizontal plane were more accurate than those for the vertical component of the wind. One of the most significant results of this project is the fact that this work allowed helping the manufacturers to improve the propeller anemometers; their accuracy was reduced by more than 5%. In addition, the development of a program to log the wind speed data from the ultrasonic anemometer eliminated the need for an expensive data logger.