Wind Loading of Antennas
Calculation of the wind surface and the wind load of antennas
Often, it is best if the antenna is installed at the highest point in a given area. It is commonly known that the wind is at its highest there and therefore it is important to take wind loading into consideration.
The figure shows the proportion between wind load F in Newton and wind surface A w in m 2 .
However, this can only be shown at a certain wind speed v. In the curve the wind speed is fixed at 150 kilometres per hour.
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| Wind Loading (Large drawing) |
As shown in the table F=1111*A w here a dynamic wind pressure q=0.64*v2=1111 is fixed.
Remember to calculate speed in metres per second instead of kilometres per hour.
Aw is determined by shape factor c and effective frontal area Ap. The shape factor is a table value, for instance the shape factor is c= 1.2 for a round whip antenna. The “effective frontal area” is determined by the antennas geometrical design, for instance a cylindrical antenna will have an area of height multiplied with diametre.
The graph can be used if both wind load is known and a max. area is to be found or if the area of the antenna is known and the wind load on the antenna has to be found.
