Patent ID: 10578126

Abstract:
A tubeaxial fan housing has a planar support vane that is fixed at sides thereof to opposing interior sides of the tubular housing, toward an inlet of the housing. The support vane receives a shaft on an underside thereof, upon which a propeller is mounted near an outlet end of the housing. The support vane has a curved edge facing the propeller to change a pattern of eddies generated downstream of the support plate and thereby reduce the noise generated by the fan. The curve is an S-shape and may be a sine wave whose period is ⅕ the propeller diameter. The propeller is positioned a relatively large distance from the curved edge of the support vane to reduce further the generation of eddies. That is, the closest point of the curved edge to the propeller is one chord length, which chord is at a tip of a propeller blade. A rounded inlet bell on the housing includes a rounded surface to reduce further turbulence across the propeller and support vane to further reduce sound. The propeller has only five blades to further reduce the generation of eddies.