US 11,885,348 B2
Axial fan with trailing edge flap
Roberto Eduardo Mosiewicz, Arona (IT)
Assigned to R.E.M. HOLDING S.R.L., Milan (IT)
Appl. No. 17/438,075
Filed by R.E.M. HOLDING S.R.L., Milan (IT)
PCT Filed Mar. 16, 2020, PCT No. PCT/IB2020/052379
§ 371(c)(1), (2) Date Sep. 10, 2021,
PCT Pub. No. WO2020/188463, PCT Pub. Date Sep. 24, 2020.
Claims priority of application No. 102019000004059 (IT), filed on Mar. 20, 2019.
Prior Publication US 2022/0186741 A1, Jun. 16, 2022
Int. Cl. F04D 29/34 (2006.01); F01D 5/14 (2006.01); F04D 19/00 (2006.01)
CPC F04D 29/34 (2013.01) [F01D 5/146 (2013.01); F04D 19/002 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A blade assembly for a large dimension axial fan having a rotation axis, comprising:
a root structure intended to mechanically connect the blade assembly to a hub of the axial fan;
a blade comprising at least one radially inner portion and a radially outer portion, the radially outer portion of the blade having a simple airfoil and the radially inner portion of the blade having a composite airfoil comprising a fore semi-airfoil and an aft flap, wherein:
the semi-airfoil of the blade is assemblable with a predefined pitch angle with respect to the hub of the axial fan by means of the root structure;
the aft flap is mounted on the blade such that it can be fixed in a position comprised between a maximum deflection position and a minimum deflection position with respect to the pitch angle; and
between the fore semi-airfoil and the aft flap a channel is defined suitable for allowing a fluid flow from a face to a back of the composite airfoil.