Effect of straightening plates on jet from ducted propeller fan

Abstract

A propeller fan jet with a duct and straightening plates for the purpose of making a high velocity jet at the far away of propeller was experimentally investigated. As a result, following conclusions were obtained. When the duct and the straightening plates are attached to the propeller, the center velocity at the position away from the propeller becomes fast, because the swirl of the jet becomes weak. As the number of plates increases, the center velocity increases. But when the number of plates exceeds a certain value, the center velocity becomes slow. This is similar about the length of the plates. When the plate is tilted, the larger the tilt angle of the plate is, the slower the center speed becomes in the downstream.