Patent ID: 9404511
Filing Date: 2016-08-02
CPC Classification: F04D,F05D

Claim Text:
1. A free-tipped axial fan assembly comprising: a fan comprising a plurality of generally radially extending blades, each of the plurality of blades having a leading edge, a trailing edge, and a blade tip; and a shroud comprising a shroud barrel surrounding at least a portion of the blade tips with a tip gap being defined between the shroud barrel and the blade tips, wherein the fan has a blade tip radius R equal to the maximum radial extent of the blade tips measured at the trailing edge, and a diameter D equal to twice the blade tip radius R, wherein each of the plurality of blades has a sectional geometry which at each radius has a chord line extending between the leading edge and the trailing edge, a mean line that lies midway between opposing blade surfaces, and a thickness distribution along the mean line, where thickness is measured between the opposing blade surfaces, normal to the mean line at each position along the mean line, said thickness varying from the blade leading edge to the blade trailing edge, said thickness having a maximum value at at least one position of maximum thickness between the blade leading edge and the blade trailing edge, wherein a non-dimensional thickness distribution is defined at each radius to be the distribution of thickness divided by maximum thickness as a function of chordwise position, and wherein the maximum thickness of each of the plurality of blades exhibits a significant increase in a region adjacent the blade tip.