Combustion chamber and fuel nozzle thereof

Abstract

The invention aims to provide a combustion chamber and a fuel nozzle thereof. The fuel nozzle comprises an oil collecting ring shell, an oil collecting ring rod core and a baffle. An annular cavity is formed in the oil collecting ring shell, an air inlet hole is formed in the inner circumferential side wall of the oil collecting ring shell, and an air outlet hole is formed in the end face of the oil collecting ring shell. The oil collecting ring rod core is arranged in the annular cavity, and the baffle is arranged between the air inlet hole and the oil collecting ring rod core and used for guiding airflow to flow from the air inlet hole to the air outlet hole and preventing the airflow entering from the air inlet hole from impacting the oil collecting ring rod core. A first sealing assembly is arranged between the baffle and the inner circumference of the oil collecting ring rod core, and a second sealing assembly is arranged between the outer circumference of the oil collecting ring rod core and the outer circumferential wall face of the annular cavity. By means of the fuel nozzle, the coking phenomenon can be effectively avoided.

Description

Technical Field

[0001] The invention relates to the technical field of gas turbine engines, and in particular to a combustion chamber and a fuel nozzle thereof. Background Art

[0002] The fuel nozzle of an aircraft engine is mainly affected by the convection heat transfer from the inlet air of the combustion chamber and the radiation heat transfer of the gas in the flame tube of the combustion chamber. As the engine cycle parameters continue to increase, the temperature of the inlet air of the combustion chamber and the temperature of the gas in the flame tube of the combustion chamber continue to increase, so the thermal load of the nozzle increases accordingly, and the inner wall temperature of the fuel nozzle oil circuit and the temperature of the fuel continue to increase. The higher wet wall temperature of the fuel causes thermal oxidation or thermal cracking reaction of the fuel. When the wet wall temperature of the fuel is greater than 421K, oxidation reaction will occur, and when the wet wall temperature of the fuel is greater than 699K, thermal cracking reaction will occur. After thermal oxidation or thermal cracking reaction, it will deposit and coke on the wall of the oil circuit, reducing the flow area of ​​the fuel pipeline. In severe cases, it may even block the nozzle and affect the fuel atomization effect.

[0003] The increasingly poor fuel atomization effect will lead to the deterioration of the combustion efficiency, emissions, and outlet temperature distribution of the combustion chamber, increased engine fuel consumption, reduced power performance, and it will be difficult to ensure the working life of the turbine blades, posing a serious threat to flight safety.

[0004] Therefore, it is necessary to adopt a thermal protection design for the nozzle to reduce the heating effect of external heat sources on the fuel and lower the temperature of the inner wall of the nozzle oil circuit, thereby avoiding the occurrence of coking. Summary of the invention

[0005] The object of the present invention is to provide a fuel injection nozzle which can effectively avoid the occurrence of coking.

[0006] A fuel injection nozzle for achieving the above-mentioned purpose comprises:

[0007] The oil collecting ring housing has an annular cavity inside, an air inlet hole is opened in the inner peripheral side wall of the oil collecting ring housing, and an air outlet hole is opened on the end surface of the oil collecting ring housing;

[0008] An oil collecting ring rod core is disposed in the annular cavity; and

[0009] a baffle, disposed between the air inlet and the oil collecting ring rod core, for guiding the airflow from the air inlet to the air outlet and preventing the airflow entering from the air inlet from impacting the oil collecting ring rod core;

[0010] Wherein, a first sealing component is arranged between the baffle and the inner periphery of the oil collecting ring rod core, and a second sealing component is arranged between the outer periphery of the oil collecting ring rod core and the outer peripheral wall surface of the annular cavity.

[0011] In one or more embodiments, the first sealing assembly includes a first sealing portion and a second sealing portion, the first sealing portion is protruded from the baffle plate toward the oil collecting ring rod core, the second sealing portion is protruded from the oil collecting ring rod core toward the baffle plate, and a first flow channel allowing airflow to pass is defined between the first sealing portion and the second sealing portion.

[0012] In one or more embodiments, along the axial direction of the annular cavity, the first sealing portion and the second sealing portion are arranged at the same axial position.

[0013] In one or more embodiments, the first sealing portion and the second sealing portion are trapezoidal in shape, and the first flow channel is defined between the upper bases of the two trapezoids.

[0014] In one or more embodiments, the second sealing assembly includes a third sealing portion and a fourth sealing portion, the third sealing portion protruding from the outer peripheral wall of the annular cavity toward the oil collecting ring rod core, the fourth sealing portion protruding from the oil collecting ring rod core toward the outer peripheral wall of the annular cavity, and a second flow channel allowing airflow to pass is defined between the third sealing portion and the fourth sealing portion.

[0015] In one or more embodiments, along the axial direction of the annular cavity, the third sealing portion and the fourth sealing portion are arranged at different axial positions.

[0016] In one or more embodiments, the third sealing portion and the fourth sealing portion are trapezoidal in shape, and the second flow channel is defined between waists of the two trapezoids.

[0017] In one or more embodiments, the baffle includes a main body section and a connecting section, wherein the connecting section connects the main body section and the inner peripheral wall surface of the annular cavity, and the main body section extends along the axial direction of the annular cavity toward the air outlet.

[0018] In one or more embodiments, a plurality of connecting parts are provided on the end surface of the oil collecting ring rod core along the circumference of the oil collecting ring rod core, and the oil collecting ring rod core is fixedly connected to the annular cavity through the connecting parts;

[0019] Wherein, a notch is provided in the connecting portion.

[0020] On the other hand, according to some embodiments of the present application, a combustion chamber is further provided, comprising a fuel nozzle, a flame tube and a combustion chamber casing, wherein the fuel nozzle is the fuel nozzle as described above.

[0021] The beneficial effects of the present invention are:

[0022] The fuel nozzle with this configuration reduces the direct impact of the high-temperature purge airflow on the oil collecting ring rod core and weakens the convective heating of the oil circuit of the oil collecting ring rod core by the high-temperature purge air through the combination of the baffle, the first sealing component and the second sealing component. These jointly reduce the risk of coking in the fuel nozzle.

[0023] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Moreover, the same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0025] Figure 1 shows a schematic diagram of some embodiments of the combustion chamber according to the present invention;

[0026] Figure 2 A half-section schematic diagram of some embodiments of the fuel nozzle is shown;

[0027] Figure 3 Shows a three-dimensional schematic diagram of some embodiments of the oil collecting ring housing;

[0028] Figure 4 A three-dimensional schematic diagram showing some embodiments of the oil collecting ring rod core

[0029] Figure 5 for Figure 2 A partial enlarged schematic diagram of part A in FIG.

[0030] Figure 6 A schematic diagram of the flow path of the airflow in the oil collecting ring housing is shown. DETAILED DESCRIPTION

[0031] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0033] With regard to the problem of coking that is prone to occur in existing fuel nozzles, the applicant has discovered through research that the key to the design of the gas path in the fuel nozzle is to reduce the convective heat exchange of the hot air (purge airflow) entering the nozzle to the oil collecting ring oil path, reduce the flow of secondary purge air, weaken the convective heating of the oil collecting ring oil path by the high-temperature purge air, and at the same time weaken the heat conduction of the oil collecting ring shell with a higher external temperature to the oil collecting ring oil path.

[0034] Based on this, on the one hand, according to some embodiments of the present application, a combustion chamber is provided, such as Figure 1 The schematic diagram of some embodiments of the combustion chamber is shown, and the combustion chamber of the aircraft engine includes a fuel nozzle 100, a flame tube 92 and a casing 93. As shown by the arrows, the airflow entering the combustion chamber is divided into three streams, including outer ring cavity air 901, head intake 902 and inner ring cavity air 903. The air enters the combustion chamber after being compressed by the compressor, and is mixed with the fuel output from the oil circuit in the fuel nozzle 100 and then burned in the flame tube 92. The high-temperature combustion gas generated flows backward to drive the turbine to do work.

[0035] On the other hand, in order to solve the coking problem that is easy to occur in the existing fuel nozzles, a fuel nozzle is also provided according to some embodiments of the present application. The fuel nozzle is used in the combustion chamber described in the above-mentioned embodiments. Figure 2 A half-section schematic diagram of some embodiments of the fuel nozzle 100 is shown. Figure 5 for Figure 2 A partial enlarged schematic diagram of part A in FIG.

[0036] The fuel nozzle 100 includes an oil collecting ring housing 1 , an oil collecting ring rod core 2 and a baffle 3 . Figure 3 shows a three-dimensional schematic diagram of some embodiments of the oil collecting ring housing, Figure 4 Schematic diagrams of some embodiments of the oil collecting ring rod core are shown. Figures 2 to 5 The oil collecting ring housing 1 has an annular cavity 10 inside, an air inlet 11 is provided in the inner peripheral side wall of the oil collecting ring housing 1, and an air outlet 12 is provided on the end surface of the oil collecting ring housing 1. The oil collecting ring rod core 2 is arranged in the annular cavity 10, and the baffle 3 is arranged between the air inlet 11 and the oil collecting ring rod core 2.

[0037] Figure 6The schematic diagram of the flow path of the airflow in the oil collecting ring shell is shown. The baffle 3 is used to guide the airflow to flow from the air inlet 11 in the direction indicated by the arrow a to the air outlet 12 for discharge. The airflow is blocked between the baffle 3 and the air inlet 11 to prevent the purge airflow from entering the air inlet 11 and impacting the oil collecting ring rod core 2. Due to the existence of the baffle 3 structure, the high-temperature purge airflow is prevented from directly impacting the oil collecting ring rod core 2, reducing the risk of coking in the oil circuit of the oil collecting ring rod core 2. At the same time, the baffle 3 can guide the purge airflow to blow out the fuel, preventing a small amount of fuel from being deposited in the cavity and spontaneously combusting. On the other hand, it also enhances the air atomization effect of the main nozzle fuel c, improves the combustion efficiency, and ensures that the mainstream purge airflow blows away the fuel and enhances the atomization effect.

[0038] A first sealing component 4 is provided between the baffle 3 and the inner periphery of the oil collecting ring rod core 2 , and a second sealing component 5 is provided between the outer periphery of the oil collecting ring rod core 2 and the outer peripheral wall of the annular cavity 10 .

[0039] The first sealing assembly 4 can reduce the flow of the secondary purge air along the arrow b located on the inner side of the oil collecting ring rod core 2, while the second sealing assembly 5 can reduce the flow of the secondary purge air along the arrow b located on the outer side of the oil collecting ring rod core 2. The combination of the two can reduce the convection heating of the oil circuit of the oil collecting ring rod core 2 by the high-temperature purge air and reduce the risk of coking.

[0040] The fuel nozzle with the present configuration reduces the direct impact of the high-temperature purge airflow on the oil collecting ring rod core 2 and weakens the convective heating of the oil circuit of the oil collecting ring rod core 2 by the high-temperature purge air by setting a combination of the baffle 3, the first sealing component 4 and the second sealing component 5, which work together to reduce the risk of coking in the fuel nozzle.

[0041] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0042] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0043] In a specific embodiment of the fuel nozzle, Figure 5The first sealing assembly 4 shown includes a first sealing portion 41 and a second sealing portion 42. The first sealing portion 41 is protruded from the baffle plate 3 toward the oil collecting ring rod core 2, and the second sealing portion 42 is protruded from the oil collecting ring rod core 2 toward the baffle plate 3. A first flow channel 40 allowing airflow to pass is defined between the first sealing portion 41 and the second sealing portion 42.

[0044] In a specific embodiment of the fuel nozzle, along the axial direction x of the annular cavity 10 , the first sealing portion 41 and the second sealing portion 42 are arranged at the same axial position.

[0045] Furthermore, in a specific embodiment of the fuel nozzle, the first sealing portion 41 and the second sealing portion 42 are trapezoidal, and the first flow channel 40 is defined between the upper bases of the two trapezoids.

[0046] In a specific embodiment, the distance between the upper bases of the two trapezoids is 0.1 mm to 0.5 mm, thereby forming a small gap design, which can also reduce the vibration between the oil collecting ring rod core 2 and the oil collecting ring housing 1 when the nozzle is working in the combustion chamber, thereby increasing the service life of the nozzle.

[0047] In some other suitable embodiments, the first sealing component 4 may also be a sealing component structure with other configurations, such as a comb tooth structure.

[0048] In a specific embodiment of the fuel nozzle, the second sealing assembly 5 includes a third sealing portion 51 and a fourth sealing portion 52. The third sealing portion 51 is protruded from the outer peripheral wall of the annular cavity 10 toward the oil collecting ring rod core 2, and the fourth sealing portion 52 is protruded from the oil collecting ring rod core 2 toward the outer peripheral wall of the annular cavity 10. A second flow channel 50 allowing airflow to pass is defined between the third sealing portion 51 and the fourth sealing portion 52.

[0049] In a specific embodiment of the fuel nozzle, along the axial direction of the annular cavity 10 , the third sealing portion 51 and the fourth sealing portion 52 are arranged at different axial positions.

[0050] Furthermore, in a specific embodiment of the fuel nozzle, the third sealing portion 51 and the fourth sealing portion 52 are trapezoidal, and the second flow channel 50 is defined between the waists of the two trapezoids.

[0051] In some suitable embodiments, the second sealing component 5 may also adopt the same configuration as the first sealing component 4 .

[0052] In other suitable embodiments, the second sealing component 5 may also be a sealing component structure with other configurations, such as a comb tooth structure.

[0053] In a specific embodiment of the fuel nozzle, the baffle 3 includes a main body section 31 and a connecting section 32. The connecting section 32 connects the main body section 31 and the inner circumferential wall of the annular cavity 10. The main body section extends along the axial direction of the annular cavity toward the air outlet 12, thereby arranging the baffle 3 with a smaller parts structure, which can achieve the effect of weight reduction.

[0054] In a specific embodiment of the fuel nozzle, a plurality of connecting parts 21 are provided on the end surface of the oil collecting ring rod core 2 along the circumference of the oil collecting ring rod core 2, and the oil collecting ring rod core 2 is fixedly connected to the annular cavity through the connecting parts 21; wherein, a notch 210 is provided in the connecting part 21, and the notch 210 reduces the contact area between the connecting part and the wall surface of the annular cavity. In a specific embodiment, the connecting part 21 includes a first section 211 and a second section 212, wherein the first section 211 extends along the axial direction of the oil collecting ring rod core 2, and the second section 212 is arranged toward the radial inner side of the oil collecting ring rod core 2, and the first section 211 is provided with a notch 210. The notch 210 may be a configuration including but not limited to a through hole, a groove, etc., and by providing the notch 210, the heat conduction of the connecting part 21 to the oil path of the oil collecting ring rod core 2 is reduced while ensuring the control of the deformation of the oil collecting ring rod core 2.

[0055] In a specific embodiment of the present fuel nozzle, the oil ring rod core 2 includes a pre-combustion stage main oil circuit 22, a pre-combustion stage auxiliary oil circuit 23 and a main combustion stage oil circuit 24. The fuel of the pre-combustion stage main oil circuit 22 flows into the pre-combustion stage main oil circuit inlet 221 and flows out from the pre-combustion stage main oil circuit outlet 222. The fuel of the pre-combustion stage auxiliary oil circuit 23 flows into the pre-combustion stage auxiliary oil circuit inlet 231 and flows out from the pre-combustion stage auxiliary oil circuit outlet 232. The fuel of the main combustion stage oil circuit 24 flows into the main combustion stage oil circuit inlet 241, is sprayed out from the main nozzle 242, is mixed with air after atomization, and burns in the flame tube 92.

[0056] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it 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 or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A fuel nozzle, characterized in that: include: The oil collecting ring housing has an annular cavity inside, an air inlet hole is opened in the inner peripheral side wall of the oil collecting ring housing, and an air outlet hole is opened on the end surface of the oil collecting ring housing; An oil collecting ring rod core is disposed in the annular cavity; and a baffle, disposed between the air inlet and the oil collecting ring rod core, for guiding the airflow from the air inlet to the air outlet and preventing the airflow entering from the air inlet from impacting the oil collecting ring rod core; Wherein, a first sealing component is arranged between the baffle and the inner periphery of the oil collecting ring rod core, and a second sealing component is arranged between the outer periphery of the oil collecting ring rod core and the outer peripheral wall surface of the annular cavity.

2. The fuel nozzle according to claim 1, characterized in that The first sealing component includes a first sealing part and a second sealing part. The first sealing part is protruded from the baffle plate toward the oil collecting ring rod core, and the second sealing part is protruded from the oil collecting ring rod core toward the baffle plate. A first flow channel allowing airflow to pass is defined between the first sealing part and the second sealing part.

3. The fuel nozzle according to claim 2, characterized in that Along the axial direction of the annular cavity, the first sealing portion and the second sealing portion are arranged at the same axial position.

4. The fuel nozzle according to claim 3, characterized in that The first sealing portion and the second sealing portion are trapezoidal in shape, and the first flow channel is defined between the upper bases of the two trapezoids.

5. The fuel injection nozzle according to claim 1, characterized in that: The second sealing component includes a third sealing part and a fourth sealing part. The third sealing part is protruded from the outer peripheral wall of the annular cavity toward the oil collecting ring rod core, and the fourth sealing part is protruded from the oil collecting ring rod core toward the outer peripheral wall of the annular cavity. A second flow channel allowing airflow to pass is defined between the third sealing part and the fourth sealing part.

6. The fuel injection nozzle according to claim 5, characterized in that Along the axial direction of the annular cavity, the third sealing portion and the fourth sealing portion are arranged at different axial positions.

7. The fuel injection nozzle according to claim 6, characterized in that The third sealing portion and the fourth sealing portion are trapezoidal in shape, and the second flow channel is defined between the waists of the two trapezoids.

8. The fuel injection nozzle according to claim 1, characterized in that: The baffle includes a body section and a connecting section, wherein the connecting section connects the body section and the inner peripheral wall surface of the annular cavity, and the body section extends toward the air outlet along the axial direction of the annular cavity.

9. The fuel injection nozzle according to claim 1, characterized in that: Along the circumference of the oil collecting ring rod core, a plurality of connecting parts are provided on the end surface of the oil collecting ring rod core, and the oil collecting ring rod core is fixedly connected to the annular cavity through the connecting parts; Wherein, a notch is provided in the connecting portion.

10. A combustion chamber, comprising a fuel nozzle, a flame tube and a combustion chamber casing, characterized in that: The fuel nozzle is the fuel nozzle according to any one of claims 1 to 9.

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