Full-scale flow measurement on a tall building with a continuous-wave Doppler Lidar anemometer

• Lidar measurements from the top of building are compared to wind-tunnel measurements
• Use of Lidar for measuring velocity and turbulence intensities vertical profiles described.
• Higher Lidar scanning rates and reduced cone angle would improve data accuracy.

While building aerodynamics have been widely studied, most investigations have been conducted in wind tunnels or through computational simulation. Full-scale experiments are least common, as they are usually costly, require significant time and effort and are subject to uncontrolled meteorological conditions. This research examines the feasibility of using a continuous-wave Doppler Lidar, as opposed to traditional experimental instrumentation for flow measurements around full-scale buildings. The normalised mean velocities and the turbulence intensities measured around a full-size, nominally cuboid building in suburban terrain were compared to results from Cobra multi-hole pressure probes mounted on the full-size building and from a 1/100-scale wind-tunnel test. The normalised mean velocities measured in the tests were within 2% of each other; however, the turbulence intensities obtained from the wind-tunnel experiments were 2–6% higher than the nominal value of 14% measured in the full-scale testing. These effects appeared mainly due to the relatively low sampling frequency of the Lidar, combined with the spatial averaging over a relatively large area. It was concluded that Lidar instrumentation shows promise for characterising the flowfield around full-scale buildings, if the scanning cone angle can be reduced and the sampling rate increased.