Deflector hood
The deflector hood is the most common hood for the removal of used and polluted air in the roof area. It is used in ventilation and dedusting systems, where the exhaust air is blown as high as possible into the open, so that it mixes with the ambient air and thus dilutes it. The hood is designed so that the exit speed is approx. 5-7 m / s. As a result, a large throw is achieved while the pressure loss is kept within limits. A deflector hood is not suitable for air intake or is only suitable in exceptional cases.
The hood owes its characteristic shape to the internal rainwater drainage, which is wider than the exhaust air opening. If you were to use a roof as rain protection instead of the deflector hood, the exhaust plume would emerge from the side and thus rise less high.
