How Do Windbreaks Work?
Wind that encounters a windbreak is deflected up and over the barrier, and eventually comes back down to ground level some distance downwind. This distance is typically 10 to 20 times the windbreak’s height (H). The size and shape of the protected zone are controlled by windbreak design and placement. Factors that should be considered when designing a windbreak include: • DENSITY–Windbreaks that are dense let very little wind through. This results in a low pressure zone on the downwind side of the windbreak. This low pressure causes the wind going over the top of the windbreak to come down to the ground sooner. The result is a protected zone that is fairly calm but that does not extend very far downwind. Snow deposited behind such a windbreak occurs in a deep drift in the calm area. Windbreaks that are more porous let some air through, reducing the low pressure zone. The result is a larger protected zone that is not quite as calm as with a dense windbreak. Any snow drift tends to be s
