Cooling passageway turn
An internally-cooled turbomachine element has an airfoil extending between inboard and outboard ends. A cooling passageway is at least partially within the airfoil and has at least a first turn. Means are in the passageway for limiting a turning a loss of the first turn. The turbomachine element may result from a reengineering of an existing element configuration lacking such means.
1. An internally-cooled turbomachine element comprising:
an airfoil extending between inboard and outboard ends;
a cooling passageway at least partially within the airfoil and having at least a first turn; and
means in the passageway for limiting a turning loss of the first turn and comprising a wall essentially dividing the entirety of the first turn into first and second flowpath portions, a leading end of the wall being 1.0–3.0 hydraulic diameters upstream of the first turn.
2. The element of claim 1 wherein:
said leading end of the wall is 1.5–2.0 hydraulic diameters upstream of the first turn.
3. The element of claim 1 wherein:
the wall extends uninterrupted from upstream of the first turn to downstream of the first turn.
4. The element of claim 1 wherein:
the wall extends uninterrupted from at least 1.0 hydraulic diameters upstream of the first turn to at least a midpoint of the first turn.
5. The element of claim 1 wherein:
the turn is in excess of 90°.
6. The element of claim 1 wherein:
the turn is around an end of a wall;
the element has at least a first airfoil end feature selected from the group consisting of an inboard platform and an outboard shroud; and
the first turn is at least partially within the first airfoil end feature.
7. An internally-cooled turbomachine element comprising:
an airfoil extending between inboard and outboard ends; and
internal surface portions defining a cooling passageway at least partially within the airfoil, wherein:
the cooling passageway has a first turn from a first leg to a second leg;
a dividing wall bifurcates the cooling passageway into first and second portions and extends within the passageway along a length from a wall first end to a wall second end; and
the wall first end is 1.0–3.0 hydraulic diameters from an end of the first leg at the first turn.
8. The element of claim 7 wherein:
the first and second portions each provide 35–65% of a cross-sectional area of the cooling passageway along said length of the wall.
9. The element of claim 7 wherein:
the passageway has a second turn from the second leg to a third leg;
the wall second end is proximate an end of the third leg at the second turn.
10. The element of claim 7 wherein:
the passageway has a second turn from the second leg to a third leg;
the wall first end is 1.5–2.0 hydraulic diameters from an end of the first leg at the first turn; and
the wall second end is 1.0–3.0 hydraulic diameters from an end of the third leg at the second turn.
11. The element of claim 7 wherein:
the passageway has a second turn from the second leg to a third leg;
at the first turn, the passageway first portion is within the second portion; and
at the second turn, the passageway second portion is within the first portion.
12. The element of claim 11 wherein:
at the first turn, the passageway first portion has a smaller cross sectional area than the second portion; and
at the second turn, the passageway second portion has a smaller cross sectional area than the first portion.
13. The element of claim 11 wherein:
at the first turn, the passageway first portion has a cross-section that is less wide than a cross-section of the second portion; and
at the second turn, the passageway second portion has a cross-section that is less wide than a cross-section of the first portion.
14. The element of claim 11 wherein:
at the first turn, the passageway first portion has a cross-section that is less elongate than a cross-section of the second portion; and
at the second turn, the passageway second portion has a cross-section that is less elongate than a cross-section of the first portion.
15. The element of claim 7 being a vane and having:
an inboard platform; and
an outboard shroud.
16. The element of claim 7 wherein:
the wall has a plurality of apertures therein.
17. The element of claim 16 wherein:
the plurality of apertures are no closer than two hydraulic diameters from the first turn.
18. A method for reengineering a configuration for an internally-cooled turbomachine element from a baseline configuration to a reengineered configuration wherein the baseline configuration has an internal passageway having first and second legs and a first turn therebetween, the method comprising:
adding a wall to bifurcate the passageway into first and second portions, the wall extending within the passageway along a length from a wall first end to a wall second end; and
otherwise essentially maintaining a basic shape of the first cooling passageway.
19. The method of claim 18 wherein:
the first turn is around an end of a second wall.
20. The method of claim 18 wherein:
the wall has a series of apertures.
21. The method of claim 18 wherein:
the wall extends at least 90°around the first turn;
at the first turn, the first portion is within the second portion; and
at the first turn, a cross-section of the first portion is narrower than a cross-section of the second portion.
22. The method of claim 18 wherein:
the wall extends at least 120°around the first turn;
at the first turn, the first portion is within the second portion; and
at the first turn, a cross-section of the first portion is less elongate than a cross-section of the second portion.
23. The method of claim 18 wherein:
the wall first end is 1.0–3.0 hydraulic diameters from an end of the first leg at the first turn.
24. An internally-cooled turbomachine element comprising:
an airfoil extending between inboard and outboard ends; and
internal surface portions defining a cooling passageway at least partially within the airfoil, wherein:
the cooling passageway has a first turn from a first leg to a second leg;
a dividing wall bifurcates the cooling passageway into first and second portions and extends within the passageway along a length from a wall first end to a wall second end;
the passageway has a second turn from the second leg to a third leg;
the wall first end is 1.0–3.0 hydraulic diameters from an end of the first leg at the first turn; and
the wall second end is 1.0–3.0 hydraulic diameters from an end of the third leg at the second turn.
25. An internally-cooled turbomachine element comprising:
an airfoil extending between inboard and outboard ends; and
internal surface portions defining a cooling passageway at least partially within the airfoil, wherein:
the cooling passageway has a first turn from a first leg to a second leg;
a dividing wall bifurcates the cooling passageway into first and second portions and extends within the passageway along a length from a wall first end to a wall second end;
the passageway has a second turn from the second leg to a third leg;
at the first turn, the passageway first portion is within the second portion; and
at the second turn, the passageway second portion is within the first portion.
26. The element of claim 25 wherein:
at the first turn, the passageway first portion has a smaller cross sectional area than the second portion; and
at the second turn, the passageway second portion has a smaller cross sectional area than the first portion.
27. The element of claim 25 wherein:
at the first turn, the passageway first portion has a cross-section that is less wide than a cross-section of the second portion; and
at the second turn, the passageway second portion has a cross-section that is less wide than a cross-section of the first portion.
28. The element of claim 25 wherein:
at the first turn, the passageway first portion has a cross-section that is less elongate than a cross-section of the second portion; and
at the second turn, the passageway second portion has a cross-section that is less elongate than a cross-section of the first portion.
29. An internally-cooled turbomachine element comprising:
an airfoil extending between inboard and outboard ends; and
internal surface portions defining a cooling passageway at least partially within the airfoil, wherein:
the cooling passageway has a first turn from a first leg to a second leg;
a dividing wall bifurcates the cooling passageway into first and second portions and extends within the passageway along a length from a wall first end to a wall second end;
the wall has a plurality of apertures therein; and
the plurality of apertures are no closer than two hydraulic diameters from the first turn.
30. An internally-cooled turbomachine element comprising:
an airfoil extending between inboard and outboard ends; and
internal surface portions defining a cooling passageway at least partially within the airfoil, wherein:
the cooling passageway has a first turn from a first leg to a second leg;
a dividing wall bifurcates the cooling passageway into first and second portions and extends within the passageway along a length from a wall first end to a wall second end;
the passageway has a second turn from the second leg to a third leg;
the wall first end is proximate an end of the first leg at the first turn; and
the wall second end is proximate an end of the third leg at the second turn.