JP2012189085A - Inner surface cooling structure of high temperature part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inner surface cooling structure of a high temperature part easy in manufacture, and having high cooling performance equal to a conventional double wall structure.SOLUTION: This inner surface cooling structure of the high temperature part cools an inner surface 3 of the high temperature part 1 having an outer surface 2 heated by high temperature gas 4 by cooling air 5, and includes a heat transfer promoting member 10 integrally arranged along the inner surface in at least a part of the inner surface 3 and enhancing the heat transfer ratio, and a smoothing member 20 having a smooth surface opposed by separating a clearance to the heat transfer promoting member. The cooling air 5 flows between the heat transfer promoting member 10 and the smoothing member 20, and cools the inner surface 3 of the high temperature part by the heat transfer promoting member 10. The heat transfer promoting member 10 consists of bumps, dimples and ribs.

Description

  The present invention relates to an inner surface cooling structure of a high-temperature component such as a high-pressure turbine stationary blade in an aeronautical or industrial gas turbine.

High temperature parts such as moving blades and stationary blades in aero or industrial gas turbines are exposed to high temperature gas (for example, 1000 ° C or higher) during operation. In some cases, a high-temperature component is cooled from the inside by flowing a cooling gas (for example, cooling air) having a temperature lower than that of the high-temperature gas.
Therefore, in order to grasp the performance of such an inner surface cooling structure and enhance the cooling performance, many studies have been conventionally performed (for example, Patent Documents 1 to 3 and Non-Patent Document 1).

  As shown in FIG. 5, the inner surface cooling structure of Patent Document 1 includes at least one wall 53 having an inner portion 51 and an outer portion 52, and a plurality of flow paths 54 extending between the inner portion and the outer portion of the wall. It comprises a plurality of pins 56 forming the mesh cooling structure 55 and a plurality of turbulent flow generating portions 57 provided on at least one of the inner part and the outer part.

  As shown in FIG. 6, the inner surface cooling structure of Patent Document 2 includes at least one wall 53 having an inner portion 51 and an outer portion 52, and a plurality of flow paths 54 extending between the inner portion and the outer portion of the wall. A plurality of pins 56 forming a mesh cooling structure 55, the inner portion of the wall 53 having a plurality of dimples 61, at least one of which forms an impingement cooling hole, and at least one of the inner portions of the wall. It does not penetrate.

  As shown in FIG. 6, the inner surface cooling structure of Patent Document 3 includes at least one wall 53 having an inner portion 51 and an outer portion 52, and a plurality of flow paths 54 extending between the inner portion and the outer portion of the wall. The plurality of pins 56 forming the mesh cooling structure 55, the plurality of dimples 61 provided on the outer portion of the wall, and at least one coating (not shown) on the outer portion of the wall. Penetrates the outer portion of the wall to form impingement cooling holes, and the coating at least partially covers the impingement cooling holes.

  Non-Patent Document 1 is a research report on heat transfer of a mesh cooling structure having pins, ribs, and dimples (concave portions).

US Pat. No. 6,984,102, “HOT GAS PATH COMPONENT WITH MESH AND TURBULATED COOOLING” US Pat. No. 7,182,576, “HOT GAS PATH COMPONENT WITH MESH AND IMPINGEMENT COOOLING” US Pat. No. 7,186,084, “HOT GAS PATH COMPONENT WITH MESH AND DIMLED COOOLING”

Ronald S. Bunker and others, “IN-WALL NETWORK (MESH) COOLING AUGMENTATION OF GAS TURBINE AIRFILLS”, Proceeding of ASME Turbo Expo 2004, Power 14

  As described above, since high cooling performance is required for the high-pressure turbine stationary blade, impingement cooling, pin fin cooling, and cooling by a turbulence promoting body are generally used for the conventional inner surface cooling structure.

  In addition, due to demands for further improvement in engine performance, development of a more efficient cooling structure is currently being sought. However, since the conventional inner surface cooling structure has a complicated double wall structure, it is very difficult to manufacture, and there is a problem that it is substantially impossible to manufacture or even if manufactured, it is very expensive.

  The present invention has been developed to solve the above-described problems. That is, an object of the present invention is to provide an inner surface cooling structure of a high-temperature part that is easy to manufacture and has a high cooling performance comparable to a conventional double wall structure.

According to the present invention, the inner surface cooling structure of a high-temperature component that cools the inner surface of a high-temperature component whose outer surface is heated with a high-temperature gas with cooling air,
A heat transfer facilitating member which is integrally provided along the inner surface on at least a part of the inner surface and increases the heat transfer coefficient;
A smooth member having a smooth surface opposed to the heat transfer promotion member with a gap therebetween,
The cooling air flows between the heat transfer promotion member and the smooth member, and the inner surface of the high temperature component is cooled by the heat transfer promotion member.

According to a preferred embodiment of the present invention, the smooth member is a hollow insert installed inside a high temperature part,
The hollow insert has an impingement cooling hole for impingement cooling the inner surface of the high temperature part,
Through the impingement cooling holes, cooling air impingingly cooled the inner surface of the high-temperature component from the inside flows through the gap between the hollow insert and the inner surface.

Further, the smooth member is another part of the high-temperature component that faces the heat transfer promotion member with a gap therebetween,
The cooling air flows between the heat transfer promoting member and the another portion.

The heat transfer promoting member is composed of bumps, dimples, and ribs,
The bumps are arranged at a constant pitch in two directions intersecting the cooling air flow direction,
The dimples are arranged at a constant pitch in the two directions in a staggered arrangement with respect to the bumps,
The rib extends in the two directions and is connected between the bumps.

Moreover, with respect to the gap H between the reference surface of the inner surface of the high-temperature component and the smooth member,
The bump height h1 is 0.8H to 0.9H,
The dimple depth h2 is 0.5H to 0.7H,
The height h3 of the rib is 0.3H to 0.4H,
The cooling air collides with the bumps, climbs over the ribs, and forms turbulence while decelerating with dimples to increase the heat transfer coefficient.

  According to the configuration of the present invention, the cooling air flows between the heat transfer promoting member integrally provided along the inner surface of the high temperature component and the smooth surface of the smooth member, and the heat transfer promoting member Since the inner surface is cooled, the heat transfer coefficient of the inner surface of the high-temperature component can be increased and high cooling performance can be obtained.

Further, the smooth member is a hollow insert installed inside the high-temperature component, and the hollow insert is provided with an impingement cooling hole for impingement cooling the inner surface of the high-temperature component. The impingement cooling can be effectively performed on the inner surface, and the cooling air after impingement cooling flows through the gap between the hollow insert and the inner surface of the high-temperature part. can do.
Therefore, with this configuration, since the hollow insert is a separate part, it is easy to integrally provide the heat transfer promoting member along the inner surface of the high temperature part by precision casting or machining, and the conventional double wall structure High cooling performance comparable to can be obtained.

Further, the smooth member is a separate part of the high-temperature component that faces the heat transfer promotion member with a gap, and the cooling air is allowed to flow between the part provided with the heat transfer promotion member and the separate part having the smooth surface. The portion provided with the transfer promoting member can be cooled with a higher heat transfer rate than the other portion (having a smooth surface).
Thus, when it uses for the trailing edge part of a wing | blade, a cooling performance can be optimized by a back and it can contribute to reduction of a cooling air flow rate.

  Therefore, according to the present invention, a complicated core is not required without using a complicated double wall structure, and the productivity can be greatly improved.

It is sectional drawing of the high temperature component which has the internal surface cooling structure by this invention. It is a block diagram of the heat transfer promotion member by this invention. It is sectional drawing of each part of FIG. It is a figure which shows the performance of the internal surface cooling structure of this invention. It is a schematic diagram of the internal surface cooling structure of patent document 1. FIG. It is a schematic diagram of the internal surface cooling structure of patent documents 2 and 3.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In each figure, common portions are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a cross-sectional view of a high temperature component having an internal cooling structure according to the present invention. In this figure, (A) is a cross-sectional view of a high-pressure turbine stationary blade, which is a high-temperature component, (B) is an enlarged view of part B, and (C) is an enlarged view of part C.

In FIG. 1 (A), 1 is a stationary blade (high-temperature part) of a high-pressure turbine, 2 is a blade surface (outer surface), 3 is an inner surface of a high-temperature part, 4 is high-temperature gas, and 5 is cooling air. The outer surface of the high-temperature component 1 (the stationary blade of the high-pressure turbine) is heated by the high-temperature gas 4, and the inner surface 3 is cooled by the cooling air 5.
The high temperature component 1 is not limited to a stationary blade, and may be a moving blade or other components.

  The inner surface cooling structure of the present invention includes a heat transfer promotion member 10 and a smooth member 20.

The heat transfer promoting member 10 is provided integrally with at least a part of the inner surface 3 of the high temperature component 1 along the inner surface 3 and has a function of increasing the heat transfer rate.
In this example, the heat transfer promoting member 10 may be provided on the entire inner surface 3 of the high-temperature component 1 or may be provided only on a portion requiring a particularly high heat transfer rate.

The smooth member 20 has a smooth surface facing the heat transfer promoting member 10 with a gap. This gap is preferably constant, but may be changed as necessary.
In this example, the smooth member 20 includes a hollow insert 21 and another portion 22 of the high-temperature component 1.

The hollow insert 21 is installed inside the high temperature component 1 by being inserted into the high temperature component 1. The hollow insert 21 has an impingement cooling hole 21 a for impingement cooling the inner surface 3 of the high-temperature component 1. The position and the number of impingement cooling holes 21a are arbitrary, but it is particularly preferable to provide a large number at the leading edge of a blade that requires impingement cooling.
The low-temperature air 5 supplied to the inside of the hollow insert 21 impinges the inner surface 3 of the high-temperature component 1 from the inside through the impingement cooling holes 21a, and then the cooling air 5 after the impingement cooling becomes the outer surface (smooth surface) of the hollow insert 21. ) And the inner surface 3 of the high-temperature component 1.

The other part 22 of the hot part 1 is in this example the ventral side of the trailing edge of the wing.
The heat transfer promoting member 10 described above is provided on the back inner surface of the trailing edge of the blade, and the other part 22 of the high-temperature component faces the heat transfer promoting member 10 with a gap therebetween, and cooling after the impingement cooling described above. The air 5 flows between the heat transfer promoting member 10 and the separate portion 22.

  FIG. 2 is a configuration diagram of the heat transfer promoting member 10 according to the present invention. In this figure, (A) is the figure which looked at the heat transfer promotion member 10 from the inner side of the high temperature component 1, and (B) is the partially expanded view.

In this figure, the heat transfer promoting member 10 includes bumps 12, dimples 14, and ribs 16.
The bumps 12 are protrusions having a diameter d1 and are spaced at a constant pitch P in two directions (left and right and up and down in this figure) intersecting with the flow direction of the cooling air 5 (for example, at an angle of 45 degrees). Has been placed.
The dimples 14 are concave portions having a diameter d2, and are arranged in a zigzag arrangement shifted by 1/2 pitch with respect to the bumps 12, at a constant pitch P in the same two directions as the bumps (left and right directions and up and down directions in this figure). Has been placed.
The ribs 16 extend in the same two directions as the bumps and are arranged so as to connect the bumps 12.
In this example, the pitches P in the two directions (the horizontal direction and the vertical direction in this figure) are the same, but may be different.

FIG. 3 is a cross-sectional view of each part of FIG. In this figure, (A) is an AA sectional view, (B) is a BB sectional view, and (C) is a CC sectional view.
In this figure, 6 is a reference surface of the inner surface 3 of the high-temperature component 1, and 7 is a smooth surface of the smooth member 20 (21, 22). The reference surface 6 corresponds to, for example, the inner surface 3 of the high temperature component 1 where there is no heat transfer promoting member 10. Hereinafter, the gap between the reference surface 6 and the smooth surface 7 is defined as H.

  In the present invention, the height h1 of the bump 12 is 0.8H to 0.9H, the depth h2 of the dimple 14 is 0.5H to 0.7H, and the height h3 of the rib 16 is 0.00. It is preferably 3H to 0.4H.

In this example, the bump 12 has a truncated conical shape with a diameter d1 and a height h1, and h1 / H = 0.86.
The dimple 14 is a recess having a diameter d2 and a depth h2, and h2 / H = 0.6.
The rib 16 is a rectangular bar-shaped member having a height h3 that connects the bumps 12 and h2 / H = 0.36. In addition, the edge part of each part is provided with roundness.
The present invention is not limited to these values, and can be arbitrarily enlarged / reduced. In this case, it is preferable to set the Reynolds number to 2500 to 10,000.

FIG. 4 is a diagram showing the performance of the inner surface cooling structure of the present invention. In this figure, the horizontal axis represents the Reynolds number, and the vertical axis represents the ratio of the product H · A of the heat transfer coefficient H and the heat transfer area A to the flat plate.
Also, the four curves in the figure are for pins only, pin + dimple, pin + rib, pin + dimple + rib. Although this pin corresponds to the bump of the present invention, the pin directly connects the high temperature side and the low temperature side, whereas the bump is integrally provided only on the high temperature side and has a gap from the low temperature side. Is different.

  From this figure, it can be seen that the highest product H · A of the heat transfer coefficient H and the heat transfer area A is obtained in the case of pin + dimple + rib (combination of pin, dimple, rib). Accordingly, it can be predicted that a high heat transfer coefficient can be obtained in the case of bump + dimple + rib as in the present invention.

  According to the configuration of the present invention described above, the cooling air 5 flows between the heat transfer promoting member 10 integrally provided along the inner surface 3 of the high-temperature component 1 and the smooth surface 7 of the smooth member 20, Since the inner surface 3 of the high-temperature component is cooled by the transmission promoting member 10, the heat transfer coefficient of the inner surface of the high-temperature component can be increased and high cooling performance can be obtained.

Further, the smooth member 20 is a hollow insert 21 installed inside the high-temperature part after manufacturing the high-temperature part, and the impingement cooling hole 20a for impingement cooling the inner surface 3 of the high-temperature part is provided in the hollow insert. The inner surface 3 of the high-temperature component can be effectively impinged from the inside through the cooling hole 20a, and the cooling air 5 after impingement cooling flows through the gap between the hollow insert 21 and the inner surface 3 of the high-temperature component. The promotion member 10 can cool the inner surface 3 of the high-temperature component with a high heat transfer coefficient.
Therefore, with this configuration, the hollow insert 21 can be installed inside the high-temperature part after the high-temperature part is manufactured. Therefore, the heat transfer promoting member 10 can be integrally provided along the inner surface 3 of the high-temperature part by precision casting or machining. It is easy and high cooling performance comparable to the conventional double wall structure can be obtained.

Further, the smooth member 20 is set as another portion 22 of the high-temperature component facing the heat transfer promotion member 10 with a gap, and the cooling air 5 is provided between the portion provided with the heat transfer promotion member 10 and another portion 22 having a smooth surface. The portion (the back side inner surface) provided with the heat transfer promoting member 10 can be cooled with a higher heat transfer rate than the other portion (the abdominal side inner surface).
Thus, when it uses for the trailing edge part of a wing | blade, a cooling performance can be optimized by a back and it can contribute to reduction of a cooling air flow rate.

  Therefore, according to the present invention, a complicated core is not required without using a complicated double wall structure, and the productivity can be greatly improved.

  In addition, this invention is not limited to embodiment mentioned above, Of course, it can change variously in the range which does not deviate from the summary of this invention.

1 High-pressure turbine vane (high temperature parts),
2 wing surface (outer surface), 3 inner surface,
4 hot gas, 5 cooling air,
6 inside reference surface, 7 smooth surface,
10 heat transfer promoting members, 12 bumps,
14 dimples, 16 ribs,
20 smooth members, 21 hollow inserts,
21a impingement cooling hole,
22 Another part of high temperature parts

Claims (3)

An internal surface cooling structure for a high-temperature component that cools an internal surface of a high-temperature component whose outer surface is heated with a high-temperature gas with cooling air,
A heat transfer facilitating member which is integrally provided along the inner surface on at least a part of the inner surface and increases the heat transfer coefficient;
A smooth member having a smooth surface opposed to the heat transfer promotion member with a gap therebetween,
The cooling air flows between the heat transfer promoting member and the smooth member, and the inner surface of the high-temperature component is cooled by the heat transfer promoting member,
The heat transfer promoting member is composed of bumps, dimples, and ribs,
The bumps are arranged at a constant pitch in each of the first and second directions intersecting with the flow direction of the cooling air,
The dimples are arranged at a constant pitch in the first and second directions so that the position in the first direction and the position in the second direction deviate from the bump,
The rib has a portion extending in the first direction and connected between the bumps, and a rib extending in the second direction and connected between the bumps. The internal cooling structure for high temperature parts. The smooth member is another part of the high-temperature component that faces the heat transfer promoting member with a gap therebetween,
The internal cooling structure for a high-temperature component according to claim 1, wherein the cooling air flows between the heat transfer promoting member and the another portion. For the gap H between the reference surface of the inner surface of the high-temperature component and the smooth member,
The bump height h1 is 0.8H to 0.9H,
The dimple depth h2 is 0.5H to 0.7H,
The height h3 of the rib is 0.3H to 0.4H,
The internal cooling structure for a high-temperature component according to claim 1 or 2, wherein the cooling air collides with bumps, climbs over ribs, and forms turbulence while decelerating with dimples to increase heat transfer coefficient. .

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