Array of flow-directing elements for a gas turbine compressor

• US 9,835,166 B2
• Filed: 10/07/2014
• Issued: 12/05/2017
• Est. Priority Date: 10/08/2013
• Status: Active Grant

• Current Assignee: MTU Aero Engines AG (MTU)
• Original Assignee: MTU Aero Engines AG (MTU)
• Inventors: Schoenenborn, Harald
• Primary Examiner(s): EASTMAN, AARON ROBERT
• Application Number:
  US14/508,650
• Publication Number:
  US 20150139789A1
• Time in Patent Office: 1,155 Days
• Field of Search: 4152081
• CPC Class Codes: F01D 5/16 for counteracting blade vibration
• CPC Class Codes: F04D 29/185 Rotors consisting of a plurality of wheels
• CPC Class Codes: F04D 29/324 Blades
• CPC Class Codes: F04D 29/403 especially adapted for elastic fluid pumps
• CPC Class Codes: F05D 2230/10 by removing material
• CPC Class Codes: F05D 2260/961 by mistuning rotor blades or stator vanes with irregular interblade spacing, airfoil shape
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft
• CPC Class Codes: Y10T 29/4932 Turbomachine making
• CPC Class Codes: Y10T 29/49336 Blade making

Abstract

An array of flow-directing elements for a compressor of a gas turbine including at least one first flow-directing element and at least one second flow-directing element different from the first flow-directing element; the flow-directing elements each having a leading edge facing the gas turbine inlet, a trailing edge, a pressure side connecting them and located ahead in the direction of rotation, a suction side located opposite thereof, as well as successive chords along a stacking axis; the flow-directing elements each extending between an airfoil root proximate to the rotor and an airfoil tip remote from the rotor. The trailing edge of the first flow-directing element is, at least in a portion thereof, axially offset from the trailing edge of the second flow-directing element in a direction toward the leading edge at least in a half proximate to the airfoil tip.

Claims

1. An array of flow-directing elements for a compressor of a gas turbine, the array comprising:

at least one first flow-directing element; and

at least one second flow-directing element different from the first flow-directing element;

the first and second flow-directing elements each having a leading edge facing an inlet of the gas, a trailing edge facing away from the gas turbine inlet, a pressure side connecting the leading edge and the trailing edge and located ahead in a direction of operational rotation, a suction side located opposite of the pressure side, and successive chords along a stacking axis;

the first and second flow-directing elements each extending between an airfoil root and an airfoil tip;

the trailing edge of the first flow-directing element being, at least in a portion thereof, axially offset from the trailing edge of the second flow-directing element in a direction toward the leading edge of the first flow-directing element, at least in a half proximate to the airfoil tip; and

at least one third flow-directing element having a third flow-directing trailing edge and a third flow-directing leading edge, at least in a portion thereof, axially offset from the trailing edges of the first and second flow-directing elements in a direction toward the third flow-directing leading edge;

wherein the trailing edge of the first flow-directing element is, at least in a portion thereof, offset from the trailing edge of the second flow-directing element by at least 0.5% and no more than 15% of a chord length of the first flow-directing element.

2. The array of flow-directing elements as recited in claim 1 wherein the trailing edge of the first flow-directing element is, at least in a portion thereof, axially offset from the trailing edge of the second flow-directing element, the second flow directing element being adjacent to the first flow directing element, in a direction toward the leading edge at least in a third proximate to the airfoil tip.

3. The array of flow-directing elements as recited in claim 1 wherein the trailing edge of the first flow-directing element is, at least in a portion thereof, offset from the trailing edge of the second flow-directing element by at least 1% and no more than 10% of a chord length of the first flow-directing element.

4. The array of flow-directing elements as recited in claim 1 wherein the trailing edge of the first flow-directing element is offset from the trailing edge of the second flow-directing element in an increasing fashion toward the airfoil tip.

5. The array of flow-directing elements as recited in claim 4 wherein the trailing edge of the first flow-directing element is offset from the trailing edge of the second flow-directing element in a monotonically increasing fashion toward the airfoil tip.

6. The array of flow-directing elements as recited in claim 1 wherein the first and second flow-directing elements have natural frequencies differing by at least 1% or no more than 20%.

7. The array of flow-directing elements as recited in claim 6 wherein the natural frequencies are first or second frequencies.

8. The array of flow-directing elements as recited in claim 6 wherein the natural frequencies are bending or torsional natural frequencies.

9. The array of flow-directing elements as recited in claim 1 wherein the first flow-directing element has a different bending stiffness or torsional stiffness than the second flow-directing element.

10. The array of flow-directing elements as recited in claim 9 wherein the first flow-directing element has the different bending stiffness or torsional stiffness than the second flow-directing element in at least in the half proximate to the airfoil tip.

11. The array of flow-directing elements as recited in claim 9 wherein the first flow-directing element has a lower bending stiffness or torsional stiffness than the second flow-directing element.

12. A rotor blade or stator blade array comprising the array of flow directing elements as recited in claim 1.

13. A gas turbine comprising at least one compressor stage including an array of flow-directing elements as recited in claim 1.

14. The gas turbine as recited in claim 13 wherein the compressor stage is a high-pressure compressor stage.

15. An aircraft engine gas turbine comprising the gas turbine as recited in claim 13.

16. A method for designing an array of flow-directing elements as recited in claim 1 comprising axially offsetting the trailing edge of the first flow-directing element, at least in a portion thereof, from the trailing edge of the second flow-directing element in a direction toward the leading edge in a half proximate to the airfoil tip.

17. The array of flow-directing elements as recited in claim 1 wherein the trailing edge of the third flow-directing element is, at least in a portion thereof, offset from the trailing edge of the second flow-directing element by at least 0.5% and no more than 15% of a chord length of the first, second, or third flow-directing element.

18. The array of flow-directing elements as recited in claim 17 wherein the trailing edge of the third flow-directing element is, at least in a portion thereof, offset from the trailing edge of the first flow-directing element by at least 0.5% and no more than 15% of a chord length of the first, second, or third flow-directing element.

19. The array of flow-directing elements as recited in claim 1 wherein the trailing edge of the third flow-directing element is, at least in a portion thereof, offset from the trailing edge of the first flow-directing element by at least 0.5% and no more than 15% of a chord length of the first, second, or third flow-directing element.