Investigating the reliability of wind anemometers on floating tension-leg platforms

This article investigates the reliability of two different first-class cup anemometers and a two-dimensional ultrasonic anemometer when subjected to surge motion as normally experienced on tension-leg platforms. The experimental study was carried out using two small land-based test rigs. One of the test rigs consisted of a short mast installed on an oscillating base designed to reproduce the surge motion of a tension-leg platform. The second rig involved an identical mast installed on a fixed base and used as a reference mast. Results indicated that the two different cup anemometer models overestimated the one-minute mean wind speed when compared to the ultrasonic sensor. The overestimation increased when the sensors were subjected to surge motions, especially those having high surge frequencies. It was highest at low wind speeds and became significantly less at higher ones.