Riffled seal for a turbomachine, turbomachine and method of manufacturing a riffled seal for a turbomachine

1. A seal of a turbomachine for reducing a leakage flow through a fluid passage between a first component of the turbomachine and a second component of the turbomachine, the seal comprising

the first component with a first surface and the second component with a second surface, wherein

the first component is stiff with regard to a first force exerted perpendicularly to the first surface;

the second component is stiff with regard to a second force exerted perpendicularly to the second surface;

the first surface is opposite to the second surface; and

the first surface comprises a first surface riffle,

wherein the fluid passage is defined by the first and second components that are spaced apart, and

wherein the first surface riffle is angled substantially perpendicularly to the leakage flow through the fluid passage.

2. The seal according to claim 1 ,

wherein the first surface riffle comprises a plurality of notches.

3. The seal according to claim 2 , wherein each notch has at least one of a depth, a width and a length that is optimized for reducing the leakage flow.

4. The seal according to claim 1 , wherein

the turbomachine comprises an axis of rotation and

the first surface and the second surface are substantially extending radially from the axis of rotation or

the first surface and the second surface are substantially extending parallel to the axis of rotation.

5. The seal according to claim 1 , wherein

the first component comprises a third surface and the second component comprises a fourth surface;

the third surface is opposite to the fourth surface; and

the third surface comprises a third surface riffle and/or the fourth surface comprises a fourth surface riffle.

6. The seal according to claim 5 ,

wherein the second surface is substantially parallel to the third surface and the fourth surface.

7. The seal according to claim 5 ,

wherein the third surface and the fourth surface define boundaries of the fluid passage for the leakage flow.

8. The seal according to claim 1 , wherein the seal further comprises

a leakage flow access side,

a leakage flow exit side and

a seal strip with a horizontal seal strip extension and a vertical seal strip extension;

wherein a direction of a differential pressure between the leakage flow access side and the leakage flow exit side is substantially perpendicular to the horizontal seal strip extension.

9. The seal according to claim 1 , wherein

the first component is a rotatable part and/or a static part of the turbomachine, and

the second component is a rotatable part and/or a static part of the turbomachine.

10. The seal according to claim 1 ,

wherein the first component is a first part of a first turbine blade and the second component is a second part of the first turbine blade or the second part of a second turbine blade.

11. The seal according to claim 1 ,

wherein the first component is a first part of a first stator vane and the second component is a second part of the first stator vane or the second part of a second stator vane.

12. A turbomachine comprising

a seal according to claim 1 ,

wherein the turbomachine is a gas turbine engine.

13. The turbomachine according to claim 12 ,

wherein the seal is located in a turbine section of the turbomachine and/or in a compressor section of the turbomachine.

14. The seal according to claim 1 ,

wherein the first surface and the second surface define boundaries of the fluid passage for the leakage flow.

15. A seal of a turbomachine for reducing a leakage flow between a first component of the turbomachine and a second component of the turbomachine, the seal comprising

the first component with a first surface and a third surface and the second component with a second surface and a fourth surface, wherein

the first component is stiff with regard to a first force exerted perpendicularly to the first surface;

the second component is stiff with regard to a second force exerted perpendicularly to the second surface;

the first surface is opposite to the second surface;

the first surface comprises a first surface riffle;

the third surface is opposite to the fourth surface; and

the second surface comprises a second surface riffle, the third surface comprises a third surface riffle and/or the fourth surface comprises a fourth surface riffle,

wherein the seal is configured such that the leakage flow is diverted by a diversion angle of greater than 135 degree,

between the first surface riffle and the third surface riffle and/or

between the first surface riffle and the fourth surface riffle.

16. The seal according to claim 15 ,

wherein the seal is configured such that the leakage flow is diverted by a diversion angle of greater than substantially 180 degree,

between the first surface riffle and the third surface riffle and/or

between the first surface riffle and the fourth surface riffle.

17. A method of manufacturing a first component of a turbomachine with a reduced leakage flow between the first component and a second component of the turbomachine, the first component comprising a first surface and the second component comprising a second surface, the first surface being opposite to the second surface, particularly the first surface and the second surface defining boundaries of a fluid passage for the leakage flow;

the method comprising

fabrication of a first surface riffle in the first surface, by grinding and/or by electrical discharge machining.