Search Results
Towers distort the wind flow and thereby may produce errors in wind speed and direction measurements obtained by anemometers mounted on them. To study this effect, a comparison was made of 5000 hourly wind observations obtained from each of two Aerovanes operating simultaneously. One was mounted on a lattice-type tower and the other was mounted on a utility pole free from the tower wind-shadow effect. Both instruments were located at the meteorological field site of the Argonne National Laboratory. The results show that there was a substantial reduction in the wind speed indicated by the tower-mounted anemometer when the wind passed through the tower before being measured. For some wind directions, the tower-mounted anemometer gave speed readings appreciably higher than those of the reference anemometer. Wind-direction measurements were also affected. The data indicate that for precise work the tower wind-shadow effect must be considered.
Towers distort the wind flow and thereby may produce errors in wind speed and direction measurements obtained by anemometers mounted on them. To study this effect, a comparison was made of 5000 hourly wind observations obtained from each of two Aerovanes operating simultaneously. One was mounted on a lattice-type tower and the other was mounted on a utility pole free from the tower wind-shadow effect. Both instruments were located at the meteorological field site of the Argonne National Laboratory. The results show that there was a substantial reduction in the wind speed indicated by the tower-mounted anemometer when the wind passed through the tower before being measured. For some wind directions, the tower-mounted anemometer gave speed readings appreciably higher than those of the reference anemometer. Wind-direction measurements were also affected. The data indicate that for precise work the tower wind-shadow effect must be considered.
