Gas turbine combustion chamber

Abstract

The present application belongs to the technical field of gas turbine combustion chamber design, and specifically relates to a gas turbine combustion chamber, comprising: an outer wall of a combustion chamber, which is annular; an outer wall of a combustion chamber, which is annular and arranged inside the outer wall; a plurality of combustion chamber heads, which are distributed circumferentially at the inlet portion between the outer wall of the combustion chamber and the inner wall of the combustion chamber, and have an annular transition section at the outer periphery; each transition section is connected between the outer wall of the combustion chamber and the inner wall of the combustion chamber, and has a plurality of cooling holes thereon, wherein the cooling holes close to the outer wall of the combustion chamber have a relatively large density and / or radius.

Description

Technical Field

[0001] The present application belongs to the technical field of general combustion engine and gas turbine design, and specifically relates to a gas turbine combustion chamber. Background Art

[0002] The intense combustion of fuel in the combustion chamber of a gas turbine under high temperature conditions will produce unsteady heat release pulsations that excite pressure disturbances in the combustion chamber, leading to oscillating combustion in the combustion chamber, generating local high temperatures, and causing serious ablation of the wall structure of the combustion chamber in a short period of time, causing the overall performance of the gas turbine to drop sharply.

[0003] At present, in order to suppress the oscillating combustion in the combustion chamber of a gas turbine and prevent local high temperature from causing serious ablation of the wall structure of the combustion chamber, air film holes are usually opened on the inner and outer walls of the combustion chamber, and cooling air is introduced into the combustion chamber through the air film holes. The acoustic energy dissipation occurring at the air film holes is used to suppress the oscillating combustion in the combustion chamber, and a cooling air film is formed on the inner and outer walls of the combustion chamber to protect the wall structure of the combustion chamber from being ablated. This technical solution has the following defects:

[0004] 1) The air film holes on the inner and outer walls of the combustion chamber are evenly distributed. Although it is easy to process and manufacture, it is not possible to specifically protect the wall structure of the combustion chamber, especially the local high temperature of the transition section. The utilization efficiency of the cooling air is low, and there is a waste of cooling air;

[0005] 2) Under the requirements of compact and high-performance design of combustion chambers, the geometric dimensions of combustion chambers are constantly decreasing and the energy density is constantly increasing. It is difficult to effectively suppress oscillating combustion by simply opening air film holes on the inner and outer walls of the combustion chamber.

[0006] This application is proposed in view of the above-mentioned technical defects.

[0007] It should be noted that the disclosure of the above background technology content is only used to assist in understanding the inventive concept and technical solution of the present invention, and it does not necessarily belong to the prior art of this patent application. In the absence of clear evidence that the above content has been disclosed on the filing date of this application, the above background technology should not be used to evaluate the novelty and creativity of the present application. Summary of the invention

[0008] The object of the present application is to provide a gas turbine combustion chamber to overcome or alleviate at least one of the technical deficiencies of the known technologies.

[0009] The technical solution of this application is:

[0010] A gas turbine combustion chamber, comprising:

[0011] The outer wall of the combustion chamber is annular;

[0012] The inner wall of the combustion chamber is annular and is arranged inside the outer wall;

[0013] A plurality of combustion chamber heads are distributed along the circumferential direction at the inlet portion between the outer wall of the combustion chamber and the inner wall of the combustion chamber, and the outer circumference has an annular transition section;

[0014] Each transition section is connected between the outer wall of the combustion chamber and the inner wall of the combustion chamber, and has a plurality of cooling holes thereon, wherein the cooling holes close to the outer wall of the combustion chamber have a relatively large density and / or radius.

[0015] According to at least one embodiment of the present application, in the above-mentioned gas turbine combustion chamber, the cooling holes on each transition section have a relatively large density and / or radius in the direction of flame deviation at the combustion chamber head.

[0016] According to at least one embodiment of the present application, in the above-mentioned gas turbine combustion chamber, the thickness of each transition section and the radius and perforation rate of the cooling holes thereon satisfy the following constraints:

[0017] E=E a -E b <0;

[0018]

[0019]

[0020]

[0021] in,

[0022] E is the total energy assessment factor in the combustion chamber;

[0023] E a The energy transfer factor generated by the flame at the head of the combustion chamber;

[0024] E b is the energy attenuation factor consumed by the transfer section;

[0025] N is the number of cooling holes;

[0026] R(β i ) is the real part of the acoustic impedance of the i-th cooling hole;

[0027] μ i is the normal acoustic particle velocity of the i-th cooling hole;

[0028] β i is the acoustic impedance of the i-th cooling hole;

[0029] i is the imaginary unit;

[0030] ρ is the average density of the cooling gas;

[0031] ω is the complex thermoacoustic frequency;

[0032] α i is the intermediate calculation variable of the i-th cooling hole;

[0033] r a,i is the radius of the i-th cooling hole;

[0034] σ is the penetration rate of cooling holes on the transition section;

[0035] K is the coupling coefficient related to the speed and temperature of the cooling gas flowing through the cooling hole;

[0036] ε is the thickness of the transition section.

[0037] According to at least one embodiment of the present application, in the above-mentioned gas turbine combustion chamber, the combustion chamber head includes:

[0038] Venturi tube;

[0039] The sleeve has one end sleeve disposed at the outlet end of the venturi tube, and the outer wall of the end has an annular connecting edge; the annular connecting edge is connected to the transition section;

[0040] A cyclone is arranged between the annular connecting edge and the venturi;

[0041] The baffle is sleeved on the other end of the sleeve and arranged in parallel with the transition section.

[0042] According to at least one embodiment of the present application, in the above-mentioned gas turbine combustion chamber, air film holes are provided on the outer wall and the inner wall of the combustion chamber, wherein the air film holes located at the local high temperature position in the combustion chamber have a relatively large density and / or radius.

[0043] This application has at least the following beneficial technical effects:

[0044] A gas turbine combustion chamber is provided, in which each combustion chamber head transition section is designed with cooling holes, and cooling air can be introduced into the combustion chamber through the cooling holes. On the one hand, the combustion chamber head can be protected from high-temperature ablation, and on the other hand, the combustion chamber can be cooled to protect the wall structure of the combustion chamber from ablation, and impedance conditions can be provided for sound pressure dissipation in the combustion chamber to suppress oscillating combustion in the combustion chamber. In addition, the cooling holes on each transition section are designed to be non-uniform according to the actual temperature distribution in the combustion chamber, so that the outer wall of the combustion chamber with a higher temperature can be cooled in a targeted manner, thereby improving the utilization efficiency of the cooling air and avoiding waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 is a schematic diagram of a gas turbine combustion chamber provided in an embodiment of the present application;

[0046] Figure 2 is a schematic diagram of a combustion chamber head provided in an embodiment of the present application;

[0047] Figure 3 It is a schematic diagram of a distribution of cooling holes on a transition section provided in an embodiment of the present application;

[0048] Figure 4 is a schematic diagram of another distribution of cooling holes on a transition section provided in an embodiment of the present application;

[0049] in:

[0050] 1-combustion chamber inner wall; 2-combustion chamber inner wall; 3-combustion chamber head; 4-transition section; 5-venturi tube; 6-casing; 7-swirler; 8-baffle.

[0051] In order to better illustrate this embodiment, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product. In addition, the drawings are only used for illustrative purposes and cannot be understood as limitations on this patent. DETAILED DESCRIPTION

[0052] In order to make the technical solution and advantages of the present application clearer, the technical solution of the present application will be further described in detail in detail and in detail in conjunction with the accompanying drawings. It can be understood that the specific embodiments described here are only partial embodiments of the present application, which are only used to explain the present application, not to limit the present application. It should be noted that, for the convenience of description, only the parts related to the present application are shown in the accompanying drawings, and other related parts can refer to the general design. In the absence of conflict, the embodiments in the present application and the technical features in the embodiments can be combined with each other to obtain new embodiments.

[0053] In addition, unless otherwise defined, the technical terms or scientific terms used in the description of this application shall be the common meanings understood by the general technicians in the field to which this application belongs. The words "upper", "lower", "left", "right", "center", "vertical", "horizontal", "inside", "outside" and other words indicating orientation used in the description of this application are only used to indicate the relative direction or positional relationship, and do not imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. When the absolute position of the described object changes, its relative positional relationship may also change accordingly, so it cannot be understood as a limitation on this application. The "first", "second", "third" and similar terms used in the description of this application are only used for descriptive purposes to distinguish different components, and cannot be understood as indicating or implying relative importance. The similar words "one", "one" or "the" used in the description of this application should not be understood as an absolute limitation on quantity, but should be understood as the existence of at least one. The similar words "including" or "comprising" used in the description of this application mean that the elements or objects appearing in front of the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0054] In addition, it should be noted that, unless otherwise clearly specified and limited, the words "installed", "connected", "connected" and similar terms used in the description of this application should be understood in a broad sense. For example, the connection can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, an indirect connection through an intermediate medium, or the internal connection of two components. Technical personnel in the field can understand their specific meanings in this application according to the specific circumstances.

[0055] The following is combined with Figures 1 to 4 This application is described in further detail.

[0056] A gas turbine combustion chamber, such as Figure 1 As shown, including:

[0057] The outer wall 1 of the combustion chamber is annular;

[0058] The combustion chamber inner wall 2 is annular and is arranged inside the outer wall 1;

[0059] A plurality of combustion chamber heads 3 are distributed along the circumferential direction at the inlet portion between the combustion chamber outer wall 1 and the combustion chamber inner wall 2, and the outer circumference has an annular transition section 4;

[0060] Each transition section 4 is connected between the combustion chamber outer wall 1 and the combustion chamber inner wall 2, and has a plurality of cooling holes thereon, wherein the cooling holes near the combustion chamber outer wall 1 have a relatively large density and / or radius, such as Figure 3 shown.

[0061] As for the gas turbine combustion chamber disclosed in the above-mentioned embodiment, it can be understood by those skilled in the art that each combustion chamber head 3 transition section 4 is designed with cooling holes, through which cooling air can be introduced into the combustion chamber, that is, cooling air is introduced between the outer wall 1 of the combustion chamber and the outer wall 2 of the combustion chamber. On the one hand, the combustion chamber head 3 can be protected from high-temperature ablation, and on the other hand, the combustion chamber can be cooled to protect the wall structure of the combustion chamber from being ablated. In addition, the cooling holes on each transition section 4 close to the outer wall 1 of the combustion chamber are designed to have a relatively large density and / or radius, so that the outer wall 1 of the combustion chamber with a higher temperature can be cooled in a targeted manner, thereby improving the utilization efficiency of the cooling air and avoiding waste.

[0062] In some optional embodiments, in the above-mentioned gas turbine combustion chamber, the cooling holes on each transition section 4 have a relatively large density and / or radius in the direction of the flame offset of the combustion chamber head 3. As shown in 4, the form of such cooling holes can be additionally designed on the basis of the cooling holes near the outer wall 1 of the combustion chamber having a relatively large density and / or radius, that is, the cooling holes near the outer wall 1 of the combustion chamber and in the direction of the flame offset of the combustion chamber head 3 are designed to have a relatively large density and / or radius, so as to cool the parts with higher temperatures in the combustion chamber in a targeted manner, thereby improving the utilization efficiency of the cooling gas and avoiding waste.

[0063] For the gas turbine combustion chamber disclosed in the above-mentioned embodiment, it can be understood by those skilled in the art that the design of cooling holes on the head transition section 4 of each combustion chamber head 3 can enable the pressure disturbance existing in the combustion chamber to undergo sound-to-vortex energy conversion at the cooling holes, thereby converting the sound energy into vortex energy. At this time, the outer space formed between the head transition section 4 of each combustion chamber head 3 and the outer wall 1 and the inner wall 2 of the combustion chamber can be used as a pressure diffusion cavity, which can be regarded as the back cavity of the combustion chamber, thereby providing resistance conditions for the dissipation of sound pressure in the combustion chamber.

[0064] Whether oscillating combustion will occur in the combustion chamber can be measured by the total acoustic energy E in the combustion chamber. It is assumed that there are two forms of energy conversion in the combustion chamber under consideration. One is the energy transfer factor E generated by the flame at the head of the combustion chamber. a , one is the energy attenuation factor E consumed by the transition section 4 b , when the total energy evaluation factor E in the combustion chamber is negative, the oscillating combustion in the combustion chamber can be effectively suppressed. Based on this, the thickness of each transition section 4 and the radius and perforation rate of the cooling holes thereon are designed to meet the constraints:

[0065] E=E a -E b <0;

[0066]

[0067]

[0068]

[0069] in,

[0070] E is the total energy assessment factor in the combustion chamber;

[0071] E a is the energy transfer factor generated by the flame from the combustion chamber head 3;

[0072] E b is the energy attenuation factor consumed by the transition section 4;

[0073] N is the number of cooling holes;

[0074] R(β i ) is the real part of the acoustic impedance of the i-th cooling hole;

[0075] μ i is the normal acoustic particle velocity of the i-th cooling hole;

[0076] β i is the acoustic impedance of the i-th cooling hole;

[0077] i is the imaginary unit;

[0078] ρ is the average density of the cooling gas;

[0079] ω is the complex thermoacoustic frequency;

[0080] α i is the intermediate calculation variable of the i-th cooling hole;

[0081] r a,i is the radius of the i-th cooling hole;

[0082] σ is the perforation rate of the cooling holes on the transition section 4;

[0083] K is the coupling coefficient related to the speed and temperature of the cooling gas flowing through the cooling hole, which can be obtained experimentally or calculated by an empirical formula;

[0084] ε is the thickness of the transition section 4;

[0085] The parameters mentioned above can be taken as the values ​​under typical operating conditions of the gas turbine, or the design values.

[0086] In some optional embodiments, in the above-mentioned gas turbine combustion chamber, the combustion chamber head 3, such as Figure 2 As shown, including:

[0087] Venturi 5;

[0088] The sleeve 6 has one end sleeve disposed at the outlet end of the venturi tube 5, and the outer wall of the end has an annular connecting edge; the annular connecting edge is connected to the transition section 4;

[0089] The cyclone 7 is arranged between the annular connecting edge and the venturi 5;

[0090] The baffle plate 8 is sleeved on the other end of the sleeve 6 and arranged parallel to the transition section 4 .

[0091] In some optional embodiments, in the above-mentioned gas turbine combustion chamber, there are air film holes on the outer wall 1 of the combustion chamber and the inner wall 2 of the combustion chamber, wherein the air film holes located at the local high-temperature parts of the combustion chamber have a relatively large density and / or radius, so as to specifically cool the higher temperature parts of the combustion chamber, improve the utilization efficiency of the cooling gas, and avoid waste.

[0092] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0093] So far, the technical solution of the present application has been described in conjunction with the preferred embodiments shown in the accompanying drawings. Those skilled in the art should understand that the scope of protection of the present application is obviously not limited to these specific embodiments. Without departing from the principles of the present application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the scope of protection of the present application.

Claims

1. A gas turbine combustion chamber, characterized in that: include: The outer wall (1) of the combustion chamber is annular; The inner wall (2) of the combustion chamber is annular and is arranged inside the outer wall (1); A plurality of combustion chamber heads (3) are distributed along the circumferential direction at the inlet portion between the combustion chamber outer wall (1) and the combustion chamber inner wall (2), and the outer circumference is provided with an annular transition section (4); Each transition section (4) is connected between the outer wall (1) of the combustion chamber and the inner wall (2) of the combustion chamber, and has a plurality of cooling holes thereon, wherein the cooling holes near the outer wall (1) of the combustion chamber have a relatively large density and radius; The cooling holes on each transition section (4) have a relatively large density and radius in the direction of the flame deviation of the combustion chamber head (3); The thickness of each transition section (4) and the radius and perforation rate of the cooling holes thereon satisfy the constraint: E=E a -AND b <0; in, E is the total energy assessment factor in the combustion chamber; E a is the energy transfer factor generated by the flame at the head of the combustion chamber (3); E b is the energy attenuation factor consumed by the transition section (4); N is the number of cooling holes; R(β i ) is the real part of the acoustic impedance of the i-th cooling hole; μ i is the normal acoustic particle velocity of the i-th cooling hole; β i is the acoustic impedance of the i-th cooling hole; i is the imaginary unit; ρ is the average density of the cooling gas; ω is the complex thermoacoustic frequency; α i is the intermediate calculation variable of the i-th cooling hole; r a,i is the radius of the i-th cooling hole; σ is the perforation rate of the cooling holes on the transition section (4); K is the coupling coefficient related to the speed and temperature of the cooling gas flowing through the cooling hole; ε is the thickness of the transition section (4); s i is the area of ​​the i cooling holes.

2. The gas turbine combustor according to claim 1, characterized in that: The combustion chamber head (3) comprises: Venturi tube (5); A sleeve (6), one end of which is sleeved at the outlet end of the venturi tube (5), and the outer wall of the end has an annular connecting edge; the annular connecting edge is connected to the transition section (4); A cyclone (7) is arranged between the annular connecting edge and the venturi tube (5); The baffle (8) is sleeved on the other end of the sleeve (6) and is arranged parallel to the transition section (4).

3. The gas turbine combustor according to claim 1, characterized in that: Air film holes are provided on the combustion chamber outer wall (1) and the combustion chamber outer wall (2), wherein the air film holes located at the local high temperature position in the combustion chamber have a relatively large density and / or radius.

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