CN112539419B

CN112539419B - Heat shield

Info

Publication number: CN112539419B
Application number: CN202011503408.2A
Authority: CN
Inventors: 张山子; 沈逸文; 何磊; 崔耀欣
Original assignee: Shanghai Electric Gas Turbine Co ltd
Current assignee: Shanghai Electric Gas Turbine Co ltd
Priority date: 2020-12-18
Filing date: 2020-12-18
Publication date: 2024-12-17
Anticipated expiration: 2040-12-18
Also published as: CN112539419A

Abstract

The invention provides a heat shield which comprises a supporting piece (1), a plurality of main shielding pieces (2) and a plurality of auxiliary shielding pieces (3), wherein all the main shielding pieces (2) are fixedly connected with the supporting piece (1) through fixing pieces (14), one sides of all the main shielding pieces (2) facing the combustion chamber of the gas turbine are sequentially connected to form shielding parts, an open slot is formed in one side, facing the supporting piece (1), of each adjacent main shielding piece (2), an auxiliary shielding piece (3) is arranged in the open slot, one end of each fixing piece (14) is fixed in the open slot, and the other end of each fixing piece (14) is fixed on the supporting piece (1). The heat shield is used for solving the problem that a heat shield of a combustion chamber of a gas turbine cannot effectively insulate heat in the prior art.

Description

Heat shield

Technical Field

The present invention relates to heat shields for gas turbines, and more particularly to a heat shield for a gas turbine combustor.

Background

The combustion process in a gas turbine takes place in the combustion chamber housing, which, because of its operation in a high temperature environment, requires the addition of refractory materials inside the housing for insulation. The refractory insulating layer (hereinafter referred to as a heat shield) is typically formed of a plurality of sheet-like tiles circumferentially arranged about the axis of the rotor, completely covering the inner surface of the housing. The heat shield is secured to the housing by a metal support member that contacts the sides of the heat shield. In the actual use process, in order to ensure thermal expansion, gaps exist between adjacent heat shields, so that hot gas can invade to directly reach the end parts of the supporting members, and the local areas of the supporting members are ablated in an over-temperature manner, so that the supporting members are disabled. Particularly, the supporting members are positioned at the middle and lower parts of the gaps between the heat shields, and high-temperature fuel gas enters the gaps and then directly contacts with the end parts of the supporting members, so that the end parts of the supporting members are exposed to high temperature conditions, are extremely easy to oxidize and can have fracture failure. In addition, the existence of the gap also enables the end part of the supporting member to receive heat radiation of high-temperature fuel gas, and the phenomena of thermal viscosity creep and relaxation of the supporting member material can be caused after long-time action, so that the fixing state can be invalid.

Patent publication CN1818527a proposes a heat shield on a support structure, the fixture in which is designed with a cooling system, the clamp section of which can be supplied with cooling fluid directly. However, this structure still does not avoid contact of the clamping section of the fastener with the high-temperature fuel gas and heat radiation exchange.

Patent publication CN103518100a proposes a heat shield with a heat shield that is provided with a beveled shoulder leading edge and a concave trailing edge on each side of the adjoining side wall that can overlap. But this structure is not effective in preventing intrusion of high temperature fuel gas in the case where the heat shield gap is increased.

Therefore, a new structure is required to solve the above-mentioned problems.

Disclosure of Invention

In view of the above-mentioned drawbacks of the prior art, an object of the present invention is to provide a heat shield for solving the problem that the heat shield of the combustion chamber of a gas turbine cannot effectively insulate heat in the prior art.

In order to achieve the above and other related objects, the present invention provides a heat shield comprising a support, a plurality of main shields and a plurality of auxiliary shields, wherein all the main shields are fixedly connected with the support through fixing members, all the main shields are sequentially connected to form a shielding part on one side of the main shields facing a combustion chamber of a gas turbine, an open slot is arranged between adjacent main shields on one side facing the support, the auxiliary shields are arranged in the open slot, one end of each fixing member is fixed in the open slot, and the other end of each fixing member is fixed on the support.

Preferably, the support has cooling channels provided therethrough, the secondary shield has cooling holes provided therein, the cooling channels communicate with all of the cooling holes, and the hole ends of the cooling holes face the primary shield.

Preferably, a sealing structure is arranged between the auxiliary shielding piece and the shielding part, and a through hole corresponding to the cooling hole is arranged on the sealing structure.

The sealing structure and the auxiliary shielding piece are of an integrated structure, and the sealing surface of the sealing structure is in a wave-breaking shape.

The sealing structure and the auxiliary shielding piece are of an embedded structure.

Preferably, the opening groove is further provided with a limiting clamping groove limiting one end part of the fixing piece.

Preferably, the supporting piece is provided with a positioning groove for limiting the other end part of the fixing piece.

Preferably, the main shielding member is rectangular, each of four corners of the rectangle is provided with a groove, and two corresponding grooves on two adjacent main shielding members are connected to form the open slot.

Preferably, the secondary shield is a superalloy or a refractory material.

As described above, the heat shield of the invention has the following beneficial effects:

The auxiliary shielding piece is arranged between the adjacent main shielding pieces, the auxiliary shielding piece can seal the gap between the two adjacent main shielding pieces, hot gas in the gas chamber is prevented from leaking from the gap, meanwhile, the problem that the fixing piece is opposite to the gap to cause the hot gas to leak is avoided, and the gap between the two main shielding pieces is also shortened due to the fact that the fixing piece is opposite to the gap to cause the hot gas to leak.

Drawings

Fig. 1 is a schematic view showing a mounting structure of a heat shield in the present embodiment.

Fig. 2 is a schematic view of a portion of a heat shield of fig. 1.

Fig. 3 is a schematic view showing a first sectional structure along the line A-A in fig. 1.

Fig. 4 is a schematic view showing a second sectional structure along the line A-A in fig. 1.

Description of element reference numerals

1. Support member

2. Main shield

3. Auxiliary shielding piece

4. Positioning groove

5. Cooling channel

6. Cold air side

7. Hot gas side

8. Sealing structure

9A through hole

9B hollow part

10. Second protrusion

11. Gap of

12. Groove

13. First protrusion

14. Fixing piece

15. Locking end

Detailed Description

Further advantages and effects of the present invention will become apparent to those skilled in the art from the disclosure of the present invention, which is described by the following specific examples.

As shown in fig. 1 to 4, the invention provides a heat shield, which comprises a supporting member 1, a plurality of main shielding members 2 and a plurality of auxiliary shielding members 3, wherein all the main shielding members 2 are fixedly connected with the supporting member 1 through fixing members 14, one sides of all the main shielding members 2 facing to a combustion chamber of a gas turbine are sequentially connected to form a shielding part, an open slot is formed between the adjacent main shielding members 2 at one side facing to the supporting member 1, the auxiliary shielding members 3 are arranged in the open slot, one end of the fixing members 14 are fixed in the open slot, and the other end of the fixing members 14 are fixed on the supporting member 1.

The auxiliary shielding pieces 3 are arranged between the adjacent main shielding pieces 2, the auxiliary shielding pieces 3 can seal gaps between the two adjacent main shielding pieces 2, hot gas in the gas chamber is prevented from leaking from the gaps, meanwhile, the problem that the fixing pieces 14 are dead against the gaps to cause hot gas leakage is avoided, the problem that the gaps between the two main shielding pieces 2 fail under the action of high-temperature air flow is also shortened, and the leakage of the hot gas is further reduced.

Specifically, in the present embodiment, the primary shielding member 2 and the secondary shielding member 3 are arranged in a positional relationship shown in fig. 1, one secondary shielding member 3 is arranged between each two primary shielding members 2, the shielding members are arranged on the supporting member 1 in a positional relationship shown in fig. 2, the shielding members are arranged on the side of the supporting member 1 having the positioning grooves 4, and the shielding portions are formed on the side of the supporting member. Specifically, as shown in fig. 2, in this embodiment, the main shielding member 2 is rectangular, four corners of the rectangle are respectively provided with a groove 12, in order to facilitate connection and fixation, the structure surrounding the groove 12 is two protrusions, namely a first protrusion 13 and a second protrusion 10, the second protrusion 10 protrudes from the first protrusion 13, a groove 12 is formed between the first protrusion 13 and the second protrusion 10, the first protrusion 13 is used for connecting the main shielding member 2 and the supporting member 1, the second protrusion 10 is used for heat insulation, two corresponding grooves 12 on two adjacent main shielding members 2 are connected to form an open slot, the auxiliary shielding member 3 is arranged in the open slot, a gap between two adjacent main shielding members 2 is sealed and shielded, so as to prevent the leakage of hot gas in the gas chamber, and meanwhile, if the auxiliary shielding member 3 is dislocated with the main shielding member 2 in the gas flow direction, the main shielding member 2 can be limited to move in the axial direction, and in order to ensure that the auxiliary shielding member 3 works normally, so as to realize the effect of shielding the hot gas and the auxiliary shielding member 3 is a refractory material.

Further, in order to facilitate the air on the cold air side 6 to enter the interior of the heat shield structure for cooling, the support member 1 is provided with a cooling channel 5 penetrating the support member 1, the auxiliary shield member 3 is provided with cooling holes, the cooling channel 5 is communicated with all the cooling holes, and the hole ends of the cooling holes face the main shield member 2.

The air of the cold air side 6 enters through the cooling channel 5 on the supporting piece 1 and then enters the positioning hole, the end part of the fixing piece 14 positioned in the positioning hole is cooled, the end part of the positioning piece is prevented from being heated and losing the function of fixing and locking, so that leakage of hot fuel gas and heat radiation is caused, meanwhile, the air also enters into the open slot through the cooling hole, the other end part of the fixing piece 14 fixed in the open slot is cooled, and the end part of the fixing piece 14 is prevented from being heated and losing the function of fixing and locking, so that leakage of the hot fuel gas and the heat radiation is caused.

In order to further prevent leakage of hot gas and heat radiation in the combustion chamber, a sealing structure 8 is arranged between the auxiliary shielding piece 3 and the shielding part, a through hole corresponding to the cooling hole is arranged on the sealing structure 8, the through hole can ensure circulation of cold air and play a role of indirect sealing, meanwhile, the sealing structure 8 can prevent the hot gas on the hot gas side 7 from leaking into the open slot and avoid heat failure of a fixing piece 14 fixed in the open slot, and meanwhile, in order to increase sealing performance, a sealing structure 8 is arranged on a contact surface of the auxiliary shielding piece 3 and the second protrusion 10, wherein the sealing structure 8 and the auxiliary shielding piece 3 can be in an integrated structure, and the sealing surface of the sealing structure 8 is in a wavy shape.

In order to facilitate installation and positioning, the opening groove is also provided with a limiting clamping groove at one end of the limiting fixing piece 14, the supporting piece 1 is provided with a positioning groove 4 at the other end of the limiting fixing piece 14, the limiting clamping groove and the positioning groove 4 are respectively fixed at two ends of the main fixing piece 14 to realize the fixing and locking functions of the fixing piece 14, and meanwhile, the fixing groove can also be used as a circulation channel of cool air to cool the fixing piece 14 fixed in the fixing groove.

The auxiliary shielding member 3 may be in a structure shown in fig. 3, the auxiliary shielding member 3 is provided with a plurality of through holes 9a (i.e. the above cooling holes), one end of the auxiliary shielding member 3, which is in contact with the second protrusion 10, is provided with a sealing structure 8, the sealing structure 8 is provided with a through hole corresponding to the through holes 9a, and the through hole is communicated with the mounting groove 4 and the groove 12, so that air on the cold air side 6 enters from the cooling channel 5, and then enters into the groove 12 through the through hole, thereby realizing cooling of the most end part of the locking end 15, and avoiding fixing failure caused by thermal deformation of the locking end 15.

The secondary shielding member 3 may have a structure as shown in fig. 4, the secondary shielding member has a hollow portion 9b communicating with the outside, one end of the secondary shielding member 3 contacting with the second protrusion 10 on the primary shielding member 2 has a sealing structure 8, the sealing surface of the sealing structure 8 is in a wave shape, the sealing structure 8 has a plurality of communication holes (i.e. the above cooling holes), and the plurality of communication holes (i.e. the above cooling holes) are communicated with the hollow portion 9b, the air on the cold air side 6 enters from the cooling channel 5, enters into the hollow portion 9b through the communication holes, finally enters into the groove 12 and the gap between the two primary shielding members 2, thereby realizing cooling of the locking end 15 and preventing heat radiation leakage inside the heat shield.

The whole structure of the invention can realize triple protection, namely, the cooling air directly led to the gap 11 between the main shielding pieces 2 is first re-protected to prevent hot gas invasion, the sealing piece on the auxiliary shielding piece 3 is second re-protected, even if hot gas invades through the gap 11, the cooling air led to the end part of the fixing piece 14 is third re-protected to ensure that the temperature of the end part of the fixing piece 14 meets the requirement.

In summary, the heat shield of the invention can effectively reduce the harmful effects of heat gas leakage and heat radiation caused by the heat shield gap 11, can greatly avoid the contact between the end of the fixing piece 14 and the heat gas, ensures the normal temperature of the end of the fixing piece 14, and reduces the failure risk.

Therefore, the invention effectively overcomes various defects in the prior art and has high industrial utilization value.

The above embodiments are merely illustrative of the principles of the present invention and its effectiveness, and are not intended to limit the invention. Modifications and variations may be made to the above-described embodiments by those skilled in the art without departing from the spirit and scope of the invention. Accordingly, it is intended that all equivalent modifications and variations of the invention be covered by the claims, which are within the ordinary skill of the art, be within the spirit and scope of the present disclosure.

Claims

1. A heat shield for a gas turbine combustion chamber, characterized in that it comprises: a support member (1), a plurality of main shielding members (2) and a plurality of secondary shielding members (3), wherein all the main shielding members (2) are fixedly connected to the support member (1) via a fixing member (14), and all the main shielding members (2) are connected in sequence on a side facing the gas turbine combustion chamber to form a shielding portion, and an open groove is provided between adjacent main shielding members (2) on a side facing the support member (1), and the secondary shielding member (3) is provided in the open groove, and one end of the fixing member (14) is fixed in the open groove, and the other end of the fixing member (14) is fixed to the support member (1). ); the support member (1) is provided with a cooling channel (5) penetrating the support member (1); the secondary shielding member (3) is provided with cooling holes, the cooling channel (5) is connected with all the cooling holes, and the hole ends of the cooling holes face the main shielding member (2); a sealing structure (8) is provided between the secondary shielding member (3) and the shielding portion, and the sealing structure (8) is provided with through holes corresponding to the cooling holes; the main shielding member (2) is rectangular, and a groove (12) is provided at each of the four corners of the rectangle, and the corresponding two grooves (12) on two adjacent main shielding members (2) are connected to form the open groove.

2. The heat shield according to claim 1, characterized in that the sealing structure (8) and the auxiliary shielding component (3) are an integrated structure, and the sealing surface of the sealing structure (8) is wavy.

3. The heat shield according to claim 1, characterized in that the sealing structure (8) and the auxiliary shielding component (3) are inlaid structures.

4. The heat shield according to claim 1, characterized in that: the opening groove also has a limiting groove for limiting one end of the fixing member (14).

5. The heat shield according to claim 3, characterized in that: the support member (1) is provided with a positioning groove (4) for limiting the other end of the fixing member (14).

6. The heat shield according to claim 1, characterized in that the secondary shielding component (3) is made of a high temperature resistant alloy or a refractory material.