Turbine rotor blade for gas turbine engine
View Patent ↗A rotor blade for a gas turbine engine includes a blade root ( 3 ) and an aerofoil projecting therefrom, the aerofoil having a leading edge and a trailing edge ( 5 ), a generally concave pressure surface ( 2 ) and a generally convex suction surface ( 1 ). The aerofoil shape of the blade varies in section along the length thereof such that: the chord-wise convex curvature of the rear suction surface decreases towards the tip ( 4 ) of the blade; the convex curvature of the early to mid suction surface increases towards the tip; the stagger of the aerofoil section increases towards the tip; and the trailing edge ( 5 ) is a straight line.
1. A rotor blade for a gas turbine engine, the blade comprising:
a blade root and an aerofoil projecting therefrom, the aerofoil having a leading edge and a trailing edge, a generally concave pressure surface, a generally convex suction surface, a tip section including a tip, and the aerofoil having a shape that varies in section along the length of the airfoil such that the aerofoil comprises:
a chord-wise convex curvature of the rear suction surface that decreases towards the tip of the blade;
a convex curvature of the early to mid suction surface that increases towards the tip;
a stagger of the aerofoil section that increases towards the tip; and
the trailing edge comprises a straight line.
2. A rotor blade for a gas turbine engine, the blade comprising:
a blade root and an aerofoil projecting therefrom, the aerofoil having a leading edge and a trailing edge, a generally concave pressure surface, a generally convex suction surface, a tip section including a tip, and the aerofoil having a shape that varies in section along the length thereof of the airfoil such that the aerofoil comprises:
a chord-wise convex curvature of the rear suction surface that decreases towards the tip of the blade;
a convex curvature of the early to mid suction surface that increases towards the tip;
a stagger of the aerofoil section that increases towards the tip;
the trailing edge comprises a straight line; and
wherein the increase in stagger is such as to give rise to chord-wise convex curvature on the pressure surface.
3. A rotor blade according to claim 1 , wherein the straight line of the trailing edge extends radially relative to the axis of rotation of the blade when in use.
4. A rotor blade according to claim 1 , wherein the straight line of the trailing edge extends at an angle to the radial direction relative to the axis of rotation of the blade.
5. A rotor blade for a gas turbine engine, the blade comprising:
a blade root and an aerofoil projecting therefrom, the aerofoil having a leading edge and a trailing edge, a generally concave pressure surface, a generally convex suction surface, a tip section including a tip, and the aerofoil having a shape that varies in section along the length thereof of the airfoil such that the aerofoil comprises:
a chord-wise convex curvature of the rear suction surface that decreases towards the tip of the blade;
a convex curvature of the early to mid suction surface that increases towards the tip;
a stagger of the aerofoil section that increases towards the tip;
the trailing edge comprises a straight line; and
wherein the chord-wise convex curvature of the rear suction surface is eliminated in the tip section to give a flat back surface.
6. A rotor blade for a gas turbine engine, the blade comprising:
a blade root and an aerofoil projecting therefrom, the aerofoil having a leading edge and a trailing edge, a generally concave pressure surface, a generally convex suction surface, a tip section including a tip, and the aerofoil having a shape that varies in section along the length thereof of the airfoil such that the aerofoil comprises;
a chord-wise convex curvature of the rear suction surface that decreases towards the tip of the blade;
a convex curvature of the early to mid suction surface that increases towards the tip;
a stagger of the aerofoil section that increases towards the tip; and
the trailing edge comprises a straight line; and
wherein the chord-wise curvature of the rear suction surface is reversed in the tip section to give a concave back surface.
7. A rotor blade according to claim 1 , wherein a lower part of the aerofoil has a minimum radial extent of 40% and a maximum radial extent of 80% of the span.
8. A rotor blade according to claim 1 , wherein the tip section is geometrically and aerodynamically blended smoothly into a lower portion of the aerofoil.
9. A rotor blade according to claim 1 , wherein trailing edge regions of the aerofoil sections are shaped so as to be similar in 2-D plan view, and comprise a row of chord-wise running cooling holes in the trailing edge lying in a radial geometric plane.
10. A turbine rotor for a gas turbine engine, comprising a plurality of rotor blades according to claim 1 .
11. A gas turbine engine including a turbine rotor according to claim 10 .
12. A rotor blade according to claim 2 , wherein the straight line of the trailing edge extends radially relative to the axis of rotation of the blade when in use.
13. A rotor blade according to claim 2 , wherein the straight line of the trailing edge extends at an angle to the radial direction relative to the axis of rotation of the blade.