Experimental study of an ultrasonic anemometer for drone-based measurements

Wind flow patterns around building features are crucial for the safe operation of drones and urban air mobility missions. Fixed anemometer stations and computational fluid dynamics simulations face limitations in measuring airflow behind buildings. The use of a drone-mounted ultrasonic anemometer addresses these limitations by providing high-resolution measurements, flexibility in positioning, and the ability to capture real-time localized wind patterns in complex urban environments. This paper presents a wind tunnel study using full factorial design of experiment on a low-cost drone-mountable ultrasonic anemometer to be used to measure urban wind fields. Measurements under uniform flow conditions, with reference instruments, validate the anemometer's performance in airspeed and direction measurements. The study also explores the anemometer's capabilities in measuring wake characteristics behind a cylinder in turbulent flow. The results demonstrate that using compact ultrasonic anemometers for drone-based anemometry in urban environments can yield adequate measurements within specific angle of attack ranges.