US 11,753,950 B2
Rotor blade with blade root contour having a straight portion provided in a concave contour portion
Martin Pernleitner, Munich (DE); Dieter Freno, Munich (DE); Klaus Wittig, Munich (DE); Christian Eichler, Munich (DE); Lutz Friedrich, Munich (DE); and Johannes Linhard, Munich (DE)
Assigned to MTU AERO ENGINES AG, Munich (DE)
Appl. No. 17/613,507
Filed by MTU AERO ENGINES AG, Munich (DE)
PCT Filed May 18, 2020, PCT No. PCT/DE2020/000097
§ 371(c)(1), (2) Date Nov. 23, 2021,
PCT Pub. No. WO2020/239151, PCT Pub. Date Dec. 3, 2020.
Claims priority of application No. 10 2019 207 620.3 (DE), filed on May 24, 2019.
Prior Publication US 2022/0251959 A1, Aug. 11, 2022
Int. Cl. F01D 5/30 (2006.01)
CPC F01D 5/3007 (2013.01) [F05D 2220/32 (2013.01); F05D 2250/711 (2013.01); F05D 2250/712 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A rotor blade for a gas turbine, the rotor blade comprising:
an airfoil portion; and
a blade root connected to the airfoil portion,
wherein the blade root has a left and a right blade root contour with respect to a cross-sectional view,
wherein, proceeding from a lower end of the blade root, the blade root contour has at least two convex contour portions and at least two concave contour portions,
wherein, proceeding from the lower end along the blade root contour between a convex contour portion and an adjoining concave contour portion, there is provided a contour portion as a flank portion that is load-bearing in operation, and
wherein, proceeding from the lower end along the blade root contour between a concave contour portion and an adjoining convex contour portion, there is provided a contour portion as a flank portion that is not load-bearing in operation,
wherein at least one of the concave contour portions has a first arc portion, a second arc portion, and a straight portion disposed between the two arc portions, and
wherein the first arc portion has a larger first radius than the second arc portion.