Cooling system including mini channels within a turbine blade of a turbine engine
View Patent ↗A turbine blade for a turbine engine having a cooling system formed from one or more cooling channels having a plurality of mini channels. The cooling system may include first ribs forming a first passageway of mini channels in which the cross-sectional area of the cooling channel is reduced, thereby increasing the velocity of the cooling fluids and the internal heat transfer coefficient. The cooling system may also include second ribs forming a second passageway downstream from the first passageway a distance sufficient to prevent the formation of a fully developed boundary layer and allow the cooling fluids to fully expand after exiting the first passageway. The cooling channel may also include a plurality of protrusions extending from surfaces forming the cooling channel to create turbulence and prevent formation of a fully developed boundary layer.
1. A turbine blade, comprising:
a generally elongated blade having a leading edge, a trailing edge, a tip at a first end, a root coupled to the blade at an end generally opposite the first end for supporting the blade and for coupling the blade to a disc, and at least one cooling channel forming a cooling system in the blade;
at least one first rib in the at least one channel generally aligned with a longitudinal axis of the at least one cooling channel and extending from a first sidewall to a second sidewall generally opposite to the first sidewall forming a first passageway having at least two mini channels in the first passageway of the at least one cooling channel;
at least one second rib in the least one channel downstream from the first passageway, aligned with the longitudinal axis of the at least one cooling channel, and extending from the first sidewall to the second sidewall generally opposite to the first sidewall forming a second passageway having at least two mini channels in the second passageway; and
at least one first protrusion protruding from a surface generally orthogonal to the at least one first rib and forming the at least one cooling channel.
2. The turbine blade of claim 1 , wherein the at least one first protrusion comprises a plurality of protrusions protruding from a surface of the cooling system in a cooling channel and aligned at an angle greater than zero relative to the longitudinal axis of the at least one cooling channel.
3. The turbine blade of claim 1 , wherein the at least one first rib comprises a plurality of first ribs positioned substantially parallel to each other.
4. The turbine blade of claim 3 , wherein the at least one second rib comprises a plurality of second ribs positioned substantially parallel to each other.
5. The turbine blade of claim 4 , wherein the plurality of second ribs are offset generally orthogonal to a longitudinal axis of the turbine blade relative to the first ribs forming the first passageway.
6. The turbine blade of claim 1 , wherein a ratio of a distance between the at least one first rib and the at least one second rib to a hydraulic diameter of the at least one mini channel is less than about four.
7. The turbine blade of claim 1 , wherein a width of the first passageway is greater than a width of the second passageway.
8. The turbine blade of claim 7 , wherein the width of the first passageway is about 50 percent less than the width of the at least one cooling channel.
9. The turbine blade of claim 7 , wherein the at least one cooling channel is formed a serpentine shaped channel comprising a plurality of first and second passageways positioned in alternating fashion along the serpentine shaped channel.
10. The turbine blade of the claim 1 , wherein a ratio of a length of the at least one first rib to a hydraulic diameter of the at least one mini channel is less than about five.
11. The turbine blade of claim 1 , wherein an aspect ratio of the mini channel is between about ½ and about ¼.
12. The turbine blade of claim 1 , wherein the width of the first passageway is less than the width of the at least one cooling channel.
13. A turbine blade, comprising:
a generally elongated blade having a leading edge, a trailing edge, a tip at a first end, a root coupled to the blade at an end generally opposite the first end for supporting the blade and for coupling the blade to a disc, and at least one cooling channel forming a cooling system in the blade;
at least one first rib in the at least one channel generally aligned with a longitudinal axis of the at least one cooling channel and extending from a first sidewall to a second sidewall generally opposite to the first sidewall forming a first passageway having at least two mini channels in the first passageway of the at least one cooling channel;
at least one second rib in the least one channel downstream from the first passageway, aligned with the longitudinal axis of the at least one cooling channel, and extending from the first sidewall to the second sidewall generally opposite to the first sidewall forming a second passageway having at least two mini channels in the second passageway;
wherein a width of the first passageway is greater than a width of the second passageway; and
at least one first protrusion protruding from a surface of the at least one cooling channel.
14. The turbine blade of claim 13 , wherein the width of the first passageway is less than the width of the at least one cooling channel.
15. The turbine blade of claim 13 , wherein the at least one cooling channel is formed a serpentine shaped channel comprising a plurality of first and second passageways positioned in alternating fashion along the serpentine shaped channel.
16. The turbine blade of claim 13 , wherein the at least one first rib comprises a plurality of ribs positioned substantially parallel to each other and aligned with the flow of cooling fluids through the first passageway and wherein the at least one second rib comprises a plurality of ribs positioned substantially parallel to each other, offset orthogonally orthogonal to a longitudinal axis of the turbine blade and relative to the first ribs, and aligned with the longitudinal axis of the at least one cooling channel.
17. The turbine blade of claim 13 , wherein a ratio of a distance between the at least one first rib and the at least one second rib to a hydraulic diameter of the at least one mini channel is less than about four.
18. The turbine blade of the claim 13 , wherein a ratio of a length of the at least one first rib to a hydraulic diameter of the at least one mini channel is less than about five.
19. The turbine blade of claim 13 , wherein an aspect ratio of the mini channel is between about ½ and about ¼.
20. A turbine blade, comprising:
a generally elongated blade having a leading edge, a trailing edge, a tip at a first end, a root coupled to the blade at an end generally opposite the first end for supporting the blade and for coupling the blade to a disc, and at least one cooling channel forming a cooling system in the blade;
a plurality of first ribs positioned generally parallel to each other in the at least one channel, generally aligned with a longitudinal axis of the at least one cooling channel, and extending from a first sidewall to a second sidewall generally opposite to the first sidewall forming a first passageway having at least three mini channels in the first passageway;
a plurality of second ribs positioned generally parallel to each other in the least one channel downstream from the first passageway, generally aligned with the longitudinal axis of the at least one cooling channel, offset orthogonally orthogonal to a longitudinal axis of the turbine blade and relative to the first ribs, and extending from the first sidewall to the second sidewall generally opposite to the first sidewall forming a second passageway having at least three mini channels in the second passageway;
wherein a width of the first passageway is less than a width of the at least one cooling channel;
wherein the at least one cooling channel forms a serpentine shaped channel comprising a plurality of first and second passageways positioned in alternating fashion along the serpentine shaped channel; and
at least one first protrusion protruding from a surface of the cooling system in the at least one cooling channel.