BLADE OF COOLING STACK FAN (VERSIONS) Russian patent published in 2010 - IPC F04D29/38 F28F25/00 

FIELD: machine building.

SUBSTANCE: blade of cooling stack fan is made in form of hollow case and consists of butt part corresponding to round rod designed for fixing blade to hub of working wheel of fan. The blade can be installed at a required working angle. Further, the blade consists of a wing and a transition part from the butt to the wing. The latter is profiled and is formed with aerodynamic profile with chord of alternate length L along lengthwise axis of the blade, with a rounded front edge, a sharp or dull back edge located on ends of profile chord and interconnected with smooth lines of upper and lower parts of profile shape. The shape of the blade in plane is trapezoidal, converging to the end of the blade. Also the transition part of the blade is rounded in the direction to the butt end of the working wheel blade. Aerodynamic profile in normal section to lengthwise axis of the blade has a section located in the beginning of the transition section of the blade with maximal thickness of profile equal to 0.19-0.20 of length L of chord in the given cross section and located at distance from 0.28·L to 0.36·L measured from the front edge of profile along its chord. Also, the said cross section is positioned at distance S₁ from the end of the blade corresponding from 0.79 to 0.82 of length S of the blade. On the end of the blade the section with maximal thickness of profile equal to (0.10-0.12) L is located from the front edge of profile at distance equal to (0.25 to 0.40) L.

EFFECT: raised efficiency and stability of cooling stack operation.

4 cl, 8 dwg