Annular fluid oscillator nozzle combustion chamber

Abstract

The invention provides a nozzle combustion chamber of an annular fluid oscillator. Comprising a combustion chamber outer casing, a flame tube installed inside the combustion chamber outer casing, an annular oscillation generating device installed on the side face of the flame tube, a combustion chamber inner casing installed inside the flame tube, an oil conveying device connected with the annular oscillation generating device and a diffuser fixedly installed on the combustion chamber outer casing. Fuel oil is accelerated through the section of the inlet contraction section and flows through the cavity and the fluid separation device, through the coanda effect, the fuel oil in the cavity periodically flows into the backflow channels located on the periphery of the cavity, annular periodic disturbance is generated on the fuel oil flowing into the cavity from the inlet contraction section of the annular fluid oscillation device, and then the fuel oil deviates from the axial direction; and the fuel oil is sprayed towards the outlet expansion section along the fluid deflection section, so that large-range periodic direction change is realized, the fuel oil can be more sufficiently mixed with air due to the speed and direction of the periodic change of the fuel oil, the atomization uniformity of the fuel oil is improved, and the fuel oil is better combusted.

Description

Technical Field

[0001] The present invention relates to the technical fields of aero - engines and gas turbines, and particularly to an annular fluid oscillator nozzle combustion chamber. Background Art

[0002] The combustion chamber plays a crucial role in aero - engines and gas turbines and is known as the "heart of the engine". Inside the combustion chamber, fuel and air are fully mixed and then burned. The high - temperature and high - pressure gas generated drives the turbine to do work, becoming the main energy source for the engine to generate thrust.

[0003] With the continuous progress of aero - engine and gas - turbine technologies, the requirements for the combustion efficiency of the combustion chamber are also increasing day by day. For high - power equipment, a slight improvement in efficiency can often bring huge economic benefits. Therefore, the research and development of high - performance combustion chambers face a series of technical challenges: fuel combustion stability must be achieved within a diverse stable operating range inside the combustion chamber to ensure the reliability and safety of the engine; reducing the polluting exhaust gas generated during the combustion process is an important goal for sustainable development; on the premise of meeting the combustion requirements, it is particularly crucial to improve the fuel atomization effect and the mixing degree of fuel and air to further improve the combustion efficiency.

[0004] Currently, centrifugal nozzles are commonly used in aero - engine combustion chambers. This design can spray fuel into the flame tube cavity in a conical manner, promoting the breakup and atomization of the fuel liquid film. However, it also has disadvantages. Fuel atomization mainly relies on centrifugal force. At low flow rates, the rotation speed is insufficient, resulting in an increase in droplet size and uneven atomization, which affects the combustion efficiency. Summary of the Invention

[0005] The purpose of the present invention is to overcome the deficiencies of the prior art and provide an annular fluid oscillator nozzle combustion chamber to replace the flame structure of the traditional centrifugal nozzle. This annular oscillation generating device utilizes the Coanda effect to spontaneously generate periodic oscillations, can achieve self - regulation of the atomization frequency by changing the upstream pressure, and atomizes the fuel by using the oscillating shear action. A fluid with periodic changes is ejected in the outlet expansion section, enabling more uniformly sized fuel droplets to perfectly cover most areas of the head of the flame tube, further improving the overall performance of the combustion chamber.

[0006] To solve the above - mentioned technical problems, the present invention adopts the following technical solutions:

[0007] An annular fluid oscillator nozzle combustion chamber, comprising an outer casing of the combustion chamber, a flame tube installed inside the outer casing of the combustion chamber, an annular oscillation generating device installed on the side of the flame tube, an inner casing of the combustion chamber installed inside the flame tube, an oil - delivery device connected to the annular oscillation generating device, and a diffuser fixedly installed on the outer casing of the combustion chamber.

[0008] Preferably, the combustion chamber liner includes a combustion chamber liner outer shell fixedly installed on the inner wall of the combustion chamber outer casing and a combustion chamber liner inner shell fixedly installed inside the combustion chamber liner outer shell. At least one first jet hole is formed at one end of the combustion chamber liner outer shell. At least one second jet hole is formed in the front sections of both the combustion chamber liner outer shell and the combustion chamber liner inner shell. At least one set of cooling holes is formed in the rear sections of both the combustion chamber liner outer shell and the combustion chamber liner inner shell along the axial direction of the combustion chamber liner. The combustion chamber liner further includes a combustion chamber liner support plate fixedly installed on the combustion chamber liner inner shell, and the combustion chamber outer casing is fixedly installed on the combustion chamber liner support plate.

[0009] Furthermore, the ratio of the distance from the center of the second jet hole to one end of the combustion chamber liner outer shell to the total length of the combustion chamber liner is 0.2 - 0.25. The arrangement range of the cooling holes to the total length of the combustion chamber liner is 0.6 - 0.7. The length-diameter ratio of the combustion chamber liner is 1.2 - 1.5.

[0010] Even further, the number of the annular oscillation generating devices is at least one. The positions of at least one of the annular oscillation generating devices correspond one-to-one with the positions of at least one first jet hole, and a certain angle is formed between adjacent two annular oscillation generating devices.

[0011] Even further, each of the annular oscillation generating devices includes a housing. A fluid deflection section is fixedly installed at one end of the housing. An outlet expansion section is fixedly installed at the end of the fluid deflection section away from the housing. The outlet expansion section penetrates through the corresponding first jet hole and extends into the combustion chamber liner. An inlet contraction section is fixedly installed at the other end of the housing. A threaded section is fixedly installed at the end of the inlet contraction section away from the housing. A cavity is formed inside the housing. Support columns are fixedly installed on the inner wall of the housing. A fluid separation device is arranged inside the cavity. The fluid separation device is fixedly connected with the support columns, and a reflux channel is formed between the fluid separation device and the inner wall of the housing.

[0012] Even further, the fuel delivery device includes an annular oil pipe, a main oil pipe fixedly installed on the annular oil pipe, and an inlet installation hole formed on the annular oil pipe.

[0013] Even further, the inlet installation hole is a threaded hole, and the number of the inlet installation holes is at least one. At least one threaded section is threadedly installed corresponding to at least one of the inlet installation holes. The annular oil pipe is communicated with both the annular oscillation generating device and the main oil pipe. The installation angle between the main oil pipe and the annular oscillation generating device is 90° - 150°.

[0014] Even further, at least one main oil pipe is provided, and at least one of the main oil pipes is circumferentially and evenly installed on the annular oil pipe.

[0015] Further, the included angle of the inlet contraction section is 50° to 70°, the included angle of the outlet expansion section is 70° to 80°, and the ratio of the diameter of the outlet section of the outlet expansion section to the radius of the cross-section of the combustion chamber perpendicular to the axis is 0.03 to 0.1.

[0016] Further, at least one main oil pipe installation hole is provided on the outer casing of the combustion chamber. The positions of at least one main oil pipe installation hole correspond to the positions of at least one main oil pipe one by one. One end of at least one main oil pipe away from the annular oil pipe penetrates through the corresponding main oil pipe installation hole and extends to the outside of the outer casing of the combustion chamber.

[0017] Advantages of the present invention:

[0018] Compared with ordinary centrifugal nozzles, the fuel oil of the present invention is accelerated through the cross-section of the inlet contraction section, flows through the cavity and the fluid separation device. Through the Coanda effect, the fuel oil in the cavity periodically flows into the return channels around the cavity, and generates a circular periodic disturbance to the fuel oil flowing into the cavity from the inlet convergence section of the annular fluid oscillation device. Furthermore, it causes the fuel oil to deviate axially and spray out towards the outlet expansion section along the fluid deflection section, realizing a large-range periodic direction change. The periodically changing velocity direction of the fuel oil enables the fuel oil to be more fully mixed with air, improves the fuel atomization uniformity, and enables the fuel oil to burn better. There is a certain included angle between adjacent two annular oscillation generating devices, so that the jet ranges of adjacent two devices partially overlap with each other, playing a role of flame linking, making the fuel combustion range wider and improving the gas combustion efficiency. Description of the Drawings

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0020] Figure 1 It is a three-dimensional sectional structure schematic diagram of the present invention.

[0021] Figure 2 It is a three-dimensional schematic diagram of the annular oscillation generating device of the present invention.

[0022] Figure 3 It is a structural schematic diagram of the annular oscillation generating device of the present invention, where the left side is the front view of the annular oscillation generating device and the right side is the sectional view.

[0023] Figure 4 It is a three-dimensional schematic diagram of the oil delivery device of the present invention.

[0024] Figure 5 It is a three-dimensional sectional schematic diagram of the combustion chamber of the present invention.

[0025] Explanation of the markings in the figure: 1. Ring oscillator; 2. Oil transmission device; 3. Combustion chamber; 4. Outer casing of the combustion chamber; 5. Inner casing of the combustion chamber; 6. Diffuser; 7. Installation hole for the main oil pipe; 101. Threaded section; 102. Inlet contraction section; 103. Cavity; 104. Fluid deflection section; 105. Outlet expansion section; 106. Return channel; 107. Outer shell; 108. Support column; 109. Fluid separation device; 201. Main oil pipe; 202. Ring oil pipe; 203. Inlet installation hole; 301. First jet hole; 302. Second jet hole; 303. Cooling hole; 304. Outer shell of the combustion chamber; 305. Inner shell of the combustion chamber; 306. Combustion chamber support plate. Detailed implementation manners

[0026] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0027] It should be understood that when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, wholes, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or their combinations.

[0028] It should also be understood that the terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in this specification of the present invention and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" are intended to include the plural forms.

[0029] It should be further understood that the term "and / or" used in this specification of the present invention and the appended claims refers to any combination and all possible combinations of one or more of the related listed items, and includes these combinations.

[0030] Embodiment

[0031] Please refer to Figures 1-5As shown in the figure, an annular fluid oscillator nozzle combustion chamber includes an outer combustion chamber casing 4, a flame tube 3 installed inside the outer combustion chamber casing 4, an annular oscillation generating device 1 installed on the side of the flame tube 3, an inner combustion chamber casing 5 installed inside the flame tube 3, an oil supply device 2 connected to the annular oscillation generating device 1, and a diffuser 6 fixedly installed on the outer combustion chamber casing 4. The diffuser 6, the inner combustion chamber casing 5, the outer combustion chamber casing 4, the flame tube 3, the oil supply device 2, and the annular oscillation generating device 1 together form an annular fluid oscillation nozzle type combustion chamber, and the outer combustion chamber casing 4 and the inner combustion chamber casing 5 together form the combustion chamber housing.

[0032] The flame tube 3 includes a flame tube outer shell 304 fixedly installed on the inner wall of the outer combustion chamber casing 4 and a flame tube inner shell 305 fixedly installed inside the flame tube outer shell 304. At least one first jet hole 301 is provided at one end of the flame tube outer shell 304. At least one second jet hole 302 is provided in the front sections of both the flame tube outer shell 304 and the flame tube inner shell 305. At least one set of cooling holes 303 is provided in the rear sections of the flame tube outer shell 304 and the flame tube inner shell 305 along the axial direction of the flame tube 3. The flame tube 3 further includes a flame tube support plate 306 fixedly installed on the flame tube inner shell 305, and the inner combustion chamber casing 5 is fixedly installed on the flame tube support plate 306.

[0033] The area enclosed by the flame tube outer shell 304 and the flame tube inner shell 305 is the combustion area.

[0034] In this embodiment, the number of the first jet holes 301 is preferably 8 - 16, and the positions of the first jet holes 301 correspond one-to-one to the positions of the outlet expansion section 105 of the annular oscillation generating device 1. The first jet holes 301 are used for atomizing and injecting fuel.

[0035] In this embodiment, the number of the second jet holes 302 is preferably 16 - 32. The second jet holes 302 are circumferentially distributed on the flame tube outer shell 304 and the flame tube inner shell 305, and the positions of the second jet holes 302 provided on the flame tube outer shell 304 correspond to the positions of the second jet holes 302 provided on the flame tube inner shell 305. The second jet holes 302 are used for air to enter the flame tube 3.

[0036] In this embodiment, the cooling holes 303 are preferably arranged in 8 - 10 groups along the axial direction of the flame tube 3, and the number is 32 - 48. The cooling holes 303 are circumferentially distributed on the flame tube outer shell 304 and the flame tube inner shell 305, and the positions of the cooling holes 303 provided on the flame tube outer shell 304 correspond to the positions of the cooling holes 303 provided on the flame tube inner shell 305. The cooling holes 303 are used for air to enter the flame tube 3 and cool the flame tube 3.

[0037] The cooling holes are circumferentially and uniformly distributed on the inner wall and the outer wall of the combustion chamber liner. The ratio of the distance from the center of the second jet hole 302 to one end of the combustion chamber outer shell 304 to the total length of the combustion chamber 3 is 0.2 - 0.25. The arrangement range of the cooling holes 303 to the total length of the combustion chamber 3 is 0.6 - 0.7. The length-diameter ratio of the combustion chamber 3 is 1.2 - 1.5;

[0038] The number of the annular oscillation generating devices 1 is at least one. The positions of at least one annular oscillation generating device 1 correspond one by one to the positions of at least one first jet hole 301. The angles between adjacent two annular oscillation generating devices 1 are different from each other. The annular oscillation generating device 1 is made of metal;

[0039] In this embodiment, the number of the annular oscillation generating devices 1 is preferably 8 - 16, and the annular oscillation generating devices 1 are uniformly distributed on the annular oil pipe 202.

[0040] Each annular oscillation generating device 1 includes a housing 107. A fluid deflection section 104 is fixedly installed at one end of the housing 107. An outlet expansion section 105 is fixedly installed at the end of the fluid deflection section 104 away from the housing 107. The outlet expansion section 105 penetrates through the corresponding first jet hole 301 and extends into the combustion chamber 3. An inlet contraction section 102 is fixedly installed at the other end of the housing 107. A threaded section 101 is fixedly installed at the end of the inlet contraction section 102 away from the housing 107. A cavity 103 is formed inside the housing 107. A support column 108 is fixedly installed on the inner wall of the housing 107. A fluid separation device 109 is arranged inside the cavity 103. The fluid separation device 109 is fixedly connected with the support column 108. A return channel 106 is formed between the fluid separation device 109 and the inner wall of the housing 107;

[0041] The oil flow direction in the cavity 103 of the annular oscillation generating device 1 is axial, and the oil flow direction in the return channel 106 is opposite to that in the cavity 103 of the annular oscillation generating device 1.

[0042] The oil delivery device 2 includes an annular oil pipe 202, a main oil pipe 201 fixedly installed on the annular oil pipe 202, and an inlet installation hole 203 opened on the annular oil pipe 202; the fuel supply system of the engine is connected to the main oil pipe 201 and delivers fuel to the annular oil pipe 202.

[0043] The inlet installation hole 203 is a threaded hole, and the number of the inlet installation holes 203 is at least one. At least one threaded section 101 is threadedly installed corresponding to at least one inlet installation hole 203 one by one. The annular oscillation generating device 1 is installed on the annular oil pipe 202 through the cooperation of the threaded section 101 and the inlet installation hole 203. The annular oil pipe 202 is connected and communicated with both the annular oscillation generating device 1 and the main oil pipe 201. The installation angle between the main oil pipe 201 and the annular oscillation generating device 1 is 90° - 150°;

[0044] In this embodiment, the annular oil pipe 202 is a circular metal pipe, and the number of the annular oil pipes 202 is one.

[0045] There is at least one main oil pipe 201, and at least one main oil pipe 201 is circumferentially and evenly installed on the annular oil pipe 202.

[0046] In this embodiment, the main oil pipe 201 is a bendable metal pipe, and the main oil pipe 201 is connected to the fuel supply system of the engine to transport fuel into the oil delivery device 2; the number of the main oil pipes 201 is preferably 1 to 3, and the main oil pipes 201 are circumferentially and evenly distributed on the annular oil pipe 202.

[0047] The included angle of the inlet contraction section 102 is 50° to 70°, the included angle of the outlet expansion section 105 is 70° to 80°, and the ratio of the diameter of the outlet cross-section of the outlet expansion section 105 to the radius of the cross-section perpendicular to the axis of the combustion chamber 3 is 0.03 to 0.1;

[0048] At least one main oil pipe mounting hole 7 is formed in the outer casing 4 of the combustion chamber. The position of at least one main oil pipe mounting hole 7 corresponds to the position of at least one main oil pipe 201 one by one. One end of at least one main oil pipe 201 away from the annular oil pipe 202 penetrates through the corresponding main oil pipe mounting hole 7 and extends to the outside of the outer casing 4 of the combustion chamber.

[0049] Working principle: Fuel enters the annular oil pipe 202 through the main oil pipe 201 and flows from the annular oil pipe 202 into each annular oscillation generating device 1. The fuel enters the cavity 103 of the annular oscillation generating device 1 through the inlet contraction section 102. During the process of the fuel passing through the inlet contraction section 102, the cross-section of the fuel passing through the inlet contraction section 102 accelerates, flows into the cavity 103, and under the Coanda effect, part of the fuel flows along the fluid separation device 109 into the return channel 106 and flows out from the outlet of the return channel 106 at the end of the inlet, disturbing the fuel entering the cavity 103, changing the fuel flow direction to a certain extent, making the fuel flow into the opposite return flow, and then generating a disturbance in the opposite direction to the previous one on the fuel flowing into the cavity 103, so that the velocity direction of the ejected fuel changes periodically within a certain range, which can effectively improve the fuel atomization uniformity and the mixing degree of fuel and air, is beneficial to the full combustion of fuel, and reduces the emission of waste gas; at the same time, since the adjacent two annular oscillation generating devices 1 form a certain angle with each other, the injection ranges of the annular oscillation generating devices 1 overlap with each other, playing a role of flame linking, enabling the flame to spread rapidly in the cavity of the flame tube 3 and improving the gas combustion efficiency; the positions of the second jet holes 302 arranged on the flame tube outer shell 304 and the flame tube inner shell 305 correspond to each other, so that the air entering the cavity of the flame tube 3 from the combustion chamber collides with each other, reducing the air flow velocity in the cavity of the flame tube 3 and generating a vortex structure, and improving the fuel and air mixing efficiency; cooling holes 303 are provided on the flame tube outer shell 304 and the flame tube inner shell 305, which are used to balance the temperature distribution in the flame tube 3, improve the combustion efficiency and reduce the emission of pollutants at the same time.

[0050] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of various equivalent modifications or substitutions, and these modifications or substitutions should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. An annular fluid oscillator nozzle combustion chamber, characterized in that: It includes an outer casing of the combustion chamber (4), a flame tube (3) installed inside the outer casing of the combustion chamber (4), an annular oscillation generating device (1) installed on the side of the flame tube (3), an inner casing of the combustion chamber (5) installed inside the flame tube (3), an oil supply device (2) connected to the annular oscillation generating device (1), and a diffuser (6) fixedly installed on the outer casing of the combustion chamber (4).

2. The annular fluid oscillator nozzle combustion chamber according to claim 1, characterized in that, The flame tube (3) includes a flame tube outer shell (304) fixedly installed on the inner wall of the outer casing of the combustion chamber (4) and a flame tube inner shell (305) fixedly installed inside the flame tube outer shell (304). At least one first jet hole (301) is provided at one end of the flame tube outer shell (304). At least one second jet hole (302) is provided in the front sections of both the flame tube outer shell (304) and the flame tube inner shell (305). At least one set of cooling holes (303) is provided in the rear sections of the flame tube outer shell (304) and the flame tube inner shell (305) along the axial direction of the flame tube (3). The flame tube (3) further includes a flame tube support plate (306) fixedly installed on the flame tube inner shell (305), and the inner casing of the combustion chamber (5) is fixedly installed on the flame tube support plate (306).

3. The annular fluid oscillator nozzle combustion chamber according to claim 2, wherein The ratio of the distance from the center of the second jet hole (302) to one end of the flame tube outer shell (304) to the total length of the flame tube (3) is 0.2 - 0.

25. The arrangement range of the cooling holes (303) to the total length of the flame tube (3) is 0.6 - 0.

7. The aspect ratio of the flame tube (3) is 1.2 - 1.

5.

4. The annular fluid oscillator nozzle combustion chamber according to claim 2, characterized in that, The number of the annular oscillation generating devices (1) is at least one. The positions of at least one of the annular oscillation generating devices (1) correspond one by one to the positions of at least one first jet hole (301), and a certain angle is formed between adjacent two annular oscillation generating devices (1).

5. The annular fluid oscillator nozzle combustion chamber according to claim 4, characterized in that, Each annular oscillation generating device (1) includes a housing (107). A fluid deflection section (104) is fixedly installed at one end of the housing (107). An outlet expansion section (105) is fixedly installed at the end of the fluid deflection section (104) away from the housing (107). The outlet expansion section (105) penetrates through the corresponding first jet hole (301) and extends into the flame tube (3). An inlet contraction section (102) is fixedly installed at the other end of the housing (107). A threaded section (101) is fixedly installed at the end of the inlet contraction section (102) away from the housing (107). A cavity (103) is provided inside the housing (107). Support columns (108) are fixedly installed on the inner wall of the housing (107). A fluid separation device (109) is arranged inside the cavity (103). The fluid separation device (109) is fixedly connected to the support columns (108), and a reflux channel (106) is formed between the fluid separation device (109) and the inner wall of the housing (107).

6. The annular fluid oscillator nozzle combustion chamber according to claim 5, characterized in that, The oil pipeline device (2) includes an annular oil pipe (202), a main oil pipe (201) fixedly installed on the annular oil pipe (202), and an inlet mounting hole (203) formed in the annular oil pipe (202).

7. The annular fluid oscillator nozzle combustion chamber according to claim 6, characterized in that The inlet mounting hole (203) is a threaded hole, and the number of the inlet mounting holes (203) is at least one. At least one threaded section (101) is threadedly installed in one-to-one correspondence with at least one of the inlet mounting holes (203). The annular oil pipe (202) is communicated with both the annular oscillation generating device (1) and the main oil pipe (201). The installation angle between the main oil pipe (201) and the annular oscillation generating device (1) is 90° to 150°.

8. The annular fluid oscillator nozzle combustion chamber according to claim 7, characterized in that, At least one main oil pipe (201) is provided, and at least one of the main oil pipes (201) is circumferentially and evenly installed on the annular oil pipe (202).

9. The annular fluid oscillator nozzle combustion chamber according to claim 4, characterized in that, The included angle of the inlet contraction section (102) is 50° to 70°, the included angle of the outlet expansion section (105) is 70° to 80°, and the ratio of the diameter of the outlet cross-section of the outlet expansion section (105) to the radius of the cross-section of the combustion chamber (3) perpendicular to the axis is 0.03 to 0.

1.

10. The annular fluid oscillator nozzle combustion chamber according to claim 8, characterized in that, At least one main oil pipe mounting hole (7) is formed in the outer casing (4) of the combustion chamber. The position of at least one of the main oil pipe mounting holes (7) corresponds to the position of at least one main oil pipe (201) one by one. One end of at least one of the main oil pipes (201) far from the annular oil pipe (202) penetrates through the corresponding main oil pipe mounting hole (7) and extends to the outside of the outer casing (4) of the combustion chamber.

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