CN107741030B - A vane-injected low-emission combustor head with cooling structure - Google Patents

Abstract

The invention discloses a vane injection low-emission combustor head with a cooling structure. The head adopts a central staged combustion organization mode and mainly includes a main combustion stage and a precombustion stage. The main combustion stage adopts the blade opening structure, the fuel is injected axially, and it is a premixed flame to ensure low emissions under heavy working conditions. The pre-combustion stage adopts a bipolar radial swirler, which is a diffused flame to ensure stable flame and ignition performance under small working conditions. In addition, the head adopts a side-by-side three oil circuit channels, which can meet the requirements of large working conditions. The pre-combustion stage oil circuit can cool the main combustion stage oil circuit to prevent nozzle coking. Under small working conditions, the main fuel stage oil circuit does not supply oil to form a cavity, which can play the role of heat insulation protection. In addition, the pre-combustion stage adopts dual oil circuit centrifugal nozzles, which can meet the good atomization performance under different working conditions. The invention can ensure the heat protection of the head, prevent the nozzle from coking, ensure the normal and safe operation of the head, and help the combustion chamber to have good performances such as good discharge and flame stability under different working conditions.

Description

A vane-injected low-emission combustor head with cooling structure

technical field

The invention relates to the technical field of the head of a low-emission combustion chamber, in particular to a head of a low-emission combustion chamber which has a cooling structure, can prevent carbon deposition in nozzles, and is sprayed by blades.

Background technique

Civil aviation The main development trend of the combustion chamber of modern civil aviation engines is low-pollution combustion. With the increasingly stringent international aviation emission standards, the combustion chamber of civil aviation engines must meet the new emission standards. The currently adopted CAEP6 (Committee on Aviation Environmental Protection) standard has very strict regulations on pollutant emissions, especially the requirements for NOx pollution emissions; while the latest CAEP8 standard proposes to reduce NOx emissions by 15% on the CAEP6 emission standards, With the rapid development of the aviation industry and the continuous improvement of people's awareness of environmental protection, higher requirements will be put forward for the pollution emissions of gas turbine combustors in the future.

In addition to meeting the low emission performance, the head of the aero-engine combustor needs to work in a high-temperature and high-pressure environment for a long time. In order to prevent its thermal deformation and nozzle overheating carbon deposition, the head needs to be thermally protected.

To sum up, based on the practical application of engineering, the present invention designs a blade-injection low-emission head with a cooling structure. This head adopts a side-by-side three-oil circuit structure, which can prevent fuel Overheating causes carbon deposits in the nozzle, and the head has a cavity heat insulation structure, which plays the role of thermal protection of the head. The head also adopts the vane-type axial injection method, which can make the fuel and air well mixed, thereby improving the combustion efficiency and reducing the emission of pollutants.

Contents of the invention

The technical problem to be solved by the present invention is: aiming at the increasingly stringent emission standards of aero-engines in the world, the axial fuel injection method on the blades is adopted to provide a combustion chamber head capable of reducing emissions, and to work on the aero-engine combustion chamber head. The high-temperature and high-pressure environment adopts a side-by-side three-oil circuit structure to give full play to the cooling pre-combustion stage oil circuit function under different working conditions and prevent carbon deposits in the nozzle. And a heat insulation cavity is applied in the head to prevent the oil circuit from overheating and carbon deposition.

The technical scheme adopted in the present invention is: a head of a blade-jet low-emission combustion chamber with a cooling structure, which adopts a centrally graded combustion organization and a structure of three parallel oil circuits, mainly composed of an oil rod, a main body of the head, and a main combustion chamber Stage vane, main combustion stage blade sleeve, interstage section, pre-combustion stage primary swirler, pre-combustion stage secondary swirler, venturi tube, pre-combustion stage sleeve, pre-combustion stage double oil circuit centrifugal nozzle The oil rod and the head body can be integrally formed by 3D printing. The head body includes the front end of the head body and the rear end of the head body. The main combustion stage blades and the head body are 3D printed together. Each blade is axially There are main combustion stage oil holes in the positions, which are used to inject fuel and mix with air. The main combustion stage blade sleeve is set outside the main combustion stage blade and welded. The interstage section is used to isolate the pre-combustion stage and the main combustion stage. Combustion grade flame, its outer diameter has threads, can be threaded with the head body; its inner diameter is also threaded, can be connected with pre-combustion grade sleeve, pre-combustion grade primary cyclone and pre-combustion grade secondary cyclone The swirler is a radially slotted inlet swirler, and the two can be welded together with the venturi tube. In addition, the secondary cyclone of the pre-combustion stage can be welded with the pre-combustion stage sleeve to form the pre-combustion stage as a whole, and then threaded with the interstage section and the front end of the head body to form the entire head.

Among them, the oil rod and the main body of the head are integrally formed by 3D printing technology, and there are three side-by-side oil circuits inside the two, and the effective flow area of the main oil circuit is between 10mm ² -80mm ² The oil rod enters the main body of the head, and after turning around in the front end of the main body of the head, enters each blade, and then sprays out from the small hole on each blade. The pre-combustion stage dual oil circuit includes the pre-combustion stage main oil circuit and the pre-combustion stage auxiliary oil circuit, both of which are distributed on both sides of the main combustion stage oil circuit to play the role of thermal protection. Among them, the effective flow area of the main oil circuit of the pre-combustion stage is between 5mm ² and 50mm ² , and the effective flow area of the auxiliary oil circuit of the pre-combustion stage is between 1mm ² and 30mm ² . The dual-circuit oil of the pre-combustion stage flows into the main body of the head through the oil rod, and after turning around the main fuel-stage oil circuit in the front end of the head main body, it enters the rear end of the head main body and enters the dual-circuit of the pre-combustion stage Centrifugal nozzle for spraying.

Wherein, the head body includes, but is not limited to, one or more heat-insulating cavities, which can protect the oil circuit from heat.

Wherein, the number of blades of the main combustion stage is 12-36, the angle is 15°-60°, the blade thickness is 0.8-2mm, and the swirl number is 0.5-1.2. There is an oil injection hole in the axial direction of each blade, the diameter of the oil hole is 0.2-1.5mm, and the total flow rate is 60-180kg/(hr*Mpa^0.5), which can fully mix the fuel and air. Can reduce pollutant emissions.

Wherein, the pre-combustion stage dual oil circuit centrifugal nozzle is connected to the center of the main body of the head through threads, and cooperates with the Venturi tube to achieve good atomization and combustion effects. The flow rate of the small oil circuit nozzle of the pre-combustion stage dual oil circuit centrifugal nozzle is 5-30kg/(hr*Mpa^0.5), and the flow rate of the large oil circuit nozzle is 10-100kg/(hr*Mpa^0.5). The opening angle of the oil mist sprayed by the pre-combustion stage dual oil circuit centrifugal nozzle is 30-120°, and the opening angle of the venturi tube outlet is 20-70°.

Wherein, the outlet opening angle of the pre-combustion level sleeve is 10°-60°, and its opening angle is designed to match the opening angle of the Venturi tube (8), so that the state of the pre-combustion level oil mist is better, and the pre-combustion level The super flame achieves stable and efficient combustion.

Wherein, the swirl number of the primary cyclone of the pre-combustion stage is 0.3-1.2, and the swirl number of the secondary cyclone of the pre-combustion stage is 0.2-1.2.

Among them, the ratio of the effective area of the primary cyclone of the pre-combustion stage to the secondary cyclone of the pre-combustion stage is between 1:8 and 9:1, and the ratio of the overall effective area of the pre-combustion stage to the effective area of the main combustion engine is between 1:4-1:10.

Among them, the interstage section has cooling holes in the axial direction, the number is 10-36, and the hole diameter is 0.5-2mm; there are pneumatic diversion holes in the radial direction, the number is 10-36, the hole diameter is 0.1-2mm, can be matched with the outer diameter of the pre-combustion stage sleeve, and affect the reflow area of the interstage section, thereby stabilizing the flame.

Working principle of the present invention: the combustion organization mode adopts the center classification, including main combustion level and pre-combustion level structure. The main combustion stage adopts the blade opening structure, and the fuel is injected axially. After being mixed with air, it is sprayed out of the head for combustion. It is a premixed flame to ensure low emissions under large working conditions. The pre-combustion stage adopts a bipolar radial swirler and a diffusion flame to ensure flame stability, ignition performance and combustion efficiency under small working conditions. In addition, the head adopts a side-by-side three oil circuit channels, which can meet the requirements of large working conditions. The pre-combustion stage oil circuit can cool the main combustion stage oil circuit to prevent nozzle coking. Under small working conditions, the main fuel stage oil circuit does not supply oil to form a cavity, which can play the role of heat insulation protection. There is also an insulating cavity in the head for thermal protection. In addition, the pre-combustion stage adopts dual oil circuit centrifugal nozzles, which can meet the good atomization performance under different working conditions and pressures. The invention is beneficial for the combustion chamber to have good performances such as good discharge and flame stability under different working conditions, can ensure thermal protection of the head, prevent coking of the nozzle, and ensure normal and safe operation of the head.

Compared with the prior art, the present invention has the following advantages:

(1) The reliability of the head is high. The head adopts a side-by-side three oil circuit flow channel, which can meet the large working conditions. The pre-combustion stage oil circuit can cool the main combustion stage oil circuit and prevent the nozzle from coking. Under small working conditions, the main fuel stage oil circuit does not supply oil to form a cavity, which can play the role of heat insulation protection. There is also an insulating cavity in the head for thermal protection.

(2) Excellent emission performance. The head adopts the axial injection method of multiple blades, which can make the fuel and air be mixed efficiently, which is beneficial to reduce emissions. In addition, the pre-combustion stage dual-oil centrifugal nozzle is matched with the double-click radial swirler and Venturi tube, which can ensure flame stability, ignition performance and combustion efficiency under small working conditions.

(3) The processing cycle and cost are low. The head is processed by 3D printing and some parts are machined, so the processing cycle is shorter and the cost is lower.

Description of drawings

Fig. 1 is the structure schematic diagram of the vane injection low-emission combustor head with cooling structure of the present invention;

Fig. 2 is the positive triaxial view of the head of the blade-injection low-emission combustor with cooling structure of the present invention;

Fig. 3 is a schematic diagram of the three oil passage fluid domains at the head of the vane injection low-emission combustor with cooling structure of the present invention, wherein Fig. 3(a) is a positive three-axis view, Fig. 3(b) is a main view, Fig. 3(c ) is the left view;

Fig. 4 is the schematic diagram of the interstage section of the blade injection low-emission combustor head with cooling structure of the present invention, wherein, Fig. 4 (a) is a sectional view of the interstage section, and Fig. 4 (b) is a left view of the interstage section;

Fig. 5 is the venturi schematic diagram of the vane injection low-emission combustor head with cooling structure of the present invention, wherein, Fig. 5 (a) is a left view of the venturi, and Fig. 5 (b) is a sectional view of the venturi;

Fig. 6 is a schematic diagram of the pre-combustion stage primary swirler of the present invention with a blade injection low-emission combustor head with a cooling structure, wherein Fig. 6 (a) is a right view of the pre-combustion stage primary swirler, Fig. 6 (b) is a sectional view of the pre-combustion stage primary cyclone;

Fig. 7 is the schematic diagram of the pre-combustion stage secondary swirler and the pre-combustion stage sleeve of the vane injection low-emission combustor head with cooling structure of the present invention, wherein, Fig. 7 (a) is the pre-combustion stage secondary swirl Figure 7(b) is the left side view of the pre-combustion stage secondary cyclone and pre-combustion stage sleeve;

Fig. 8 is a schematic diagram of the pre-combustion stage dual oil circuit centrifugal nozzle with cooling structure blade injection low emission combustion chamber head of the present invention, wherein Fig. 8 (a) is a cross-sectional view of the pre-combustion stage dual oil circuit centrifugal nozzle, Fig. 8 ( b) is the left view of the pre-combustion stage dual oil circuit centrifugal nozzle;

Fig. 9 is a schematic diagram of the oil rod and the head body of the vane injection low-emission combustion chamber head with a cooling structure of the present invention, wherein Fig. 9 (a) is a right view of the oil rod and the head body, and Fig. 9 (b) is The sectional view of the oil rod and the main body of the head, Fig. 9(c) is a top view of the oil rod and the main body of the head.

In the figure: 1 is the oil rod, 2 is the main body of the head, 3 is the blade of the main combustion stage, 4 is the sleeve of the blade of the main combustion stage, 5 is the interstage section, 6 is the primary cyclone of the pre-combustion stage, and 7 is the pre-combustion stage Combustion level secondary cyclone, 8 is the venturi tube, 9 is the pre-combustion level sleeve, 10 is the pre-combustion level dual oil circuit centrifugal nozzle, 11 is the front end of the main body of the head, 12 is the rear end of the main body of the head, and 13 is the 14 is the main oil circuit of the pre-combustion level, 15 is the auxiliary oil circuit of the pre-combustion level, and 16 is the heat-insulating capacity cavity.

Detailed ways

Describe the present invention in detail below in conjunction with accompanying drawing and specific embodiment:

As shown in Figure 1, it is a blade-jet low-emission head with a cooling structure described in the embodiment of the present invention. It adopts a centrally graded combustion organization and a structure of three oil circuits in parallel. It is mainly composed of an oil rod 1, a head Part body 2, main combustion stage blade 3, main combustion stage blade sleeve 4, interstage section 5, pre-combustion stage primary swirler 6, pre-combustion stage secondary swirler 7, venturi tube 8, pre-combustion stage Stage sleeve 9, pre-combustion stage double oil circuit centrifugal nozzle 10 and so on. The oil rod 1 and the head body 2 can be integrally formed by 3D printing, wherein the head body 2 includes a front end 11 of the head body and a rear end 12 of the head body. The main fuel stage blade 3 and the head body 2 are 3D printed together, and each blade has a main fuel stage oil hole in the axial position, which is used to inject fuel and mix it with air. The main combustion stage vane sleeve 4 is sleeved on the outside of the main combustion stage vane 3 and welded. The interstage section 5 is used to isolate the flames of the pre-combustion stage and the main combustion stage. Its outer diameter is threaded and can be threaded with the head body 2 ; its inner diameter is also threaded and can be connected with the pre-combustion stage sleeve 9 . The primary cyclone 6 of the pre-combustion stage and the secondary cyclone 7 of the pre-combustion stage are radially slotted inlet type cyclones, and both can be welded together with the venturi tube 8 . In addition, the secondary cyclone 7 of the pre-combustion stage can be welded with the pre-combustion stage sleeve 9 to form the pre-combustion stage as a whole, and then screwed with the interstage section 5 and the head body 2 to form the entire head.

In addition, the head main body 2 includes, but is not limited to, one or more heat-insulating cavities 16, which can protect the oil circuit from heat.

As shown in Figure 2, the oil rod 1 and the head body 2 are integrally formed by 3D printing technology. Main combustion stage blades 3, the number of blades is 12-36, the angle is 15°-60°, the blade thickness is 0.8-2mm, and the swirl number is 0.5-1.2kg/(hr*Mpa^0.5). There is an oil injection hole in the axial direction of each blade, the diameter of the oil hole is 0.2-1.5mm, and the total flow rate is 60-180, which can fully mix the fuel and air and reduce the emission of pollutants.

As shown in Figure 3, there are three side-by-side oil circuits inside the head. Among them, the effective flow area of the main fuel oil circuit 13 is between 10 mm ² and 80 mm ² , the main fuel oil enters the head body 2 from the oil rod 1, and after turning around in the front end 11 of the head body, it is Spray from small holes on each blade. The pre-combustion stage dual oil circuit includes a pre-combustion stage main oil circuit 14 and a pre-combustion stage auxiliary oil circuit 15, both of which are distributed on both sides of the main combustion stage oil circuit to play a thermal protection role. Among them, the effective flow area of the pre-combustion stage main oil circuit 14 is between 5 mm ² and 50 mm ² , and the effective flow area of the pre-combustion stage auxiliary oil circuit 15 is between 1 mm ² and 30 mm ² . The two-way oil of the pre-combustion stage flows through the oil rod 1 and enters the head body 2. After turning around the main fuel stage oil circuit 13 in the front end 11 of the head body in the circumferential direction, it enters the rear end 12 of the head body and enters the pre-combustion stage. Fuel stage dual oil circuit centrifugal nozzle 10 for injection.

As shown in Figure 4, the interstage section 5 has cooling holes in the axial direction, the number is 10-36, and the hole diameter is 0.5-2mm; there are pneumatic diversion holes in the radial direction, the number is 10-36, The hole diameter is 0.1-2mm, which can be matched with the outer diameter of the pre-combustion stage sleeve 9 to affect the reflow area of the interstage section, thereby stabilizing the flame.

As shown in Figure 5, the opening angle of the outlet of the venturi tube 8 is 20-70°, and it is welded with the primary cyclone 6 of the pre-combustion stage and the secondary cyclone 7 of the pre-combustion stage.

As shown in Figure 6 and Figure 7, the swirl number of the primary cyclone 6 of the pre-combustion stage is 0.3-1.2, and the swirl number of the secondary cyclone 7 of the pre-combustion stage is 0.2-1.2. Can be reversed. The outlet opening angle of the pre-combustion stage sleeve 9 is 10°-60°, which can make the state of the pre-combustion stage oil mist better, and the pre-combustion stage flame achieves stable and efficient combustion.

As shown in Fig. 8, the centrifugal nozzle 10 of the pre-combustion stage double oil circuit is connected to the center of the head body 2 through threads, and cooperates with the venturi tube 8 to achieve good atomization and combustion effects. The flow rate of the small oil circuit nozzle of the pre-combustion stage dual oil circuit centrifugal nozzle 10 is 5-30kg/(hr*Mpa^0.5), and the flow rate of the large oil circuit nozzle is 10-100kg/(hr*Mpa^0.5). The opening angle of the oil mist sprayed by the pre-combustion stage double oil circuit centrifugal nozzle 10 is 30-120°.

As shown in FIG. 9 , the main fuel oil rod 1 , the head body 2 and the main fuel blade 3 can be integrally formed by 3D printing technology.

Claims (9)

1. a kind of blade with cooling structure sprays low emission combustor head, it is characterised in that: using center classification Combustion method, blade spray fuel oil and the side by side structure of three oil circuits, mainly by beam hanger (1), head body (2), main combustion stage Blade (3), main combustion stage blade sleeve (4), interstage section (5), pre-combustion grade level-one cyclone (6), pre-combustion grade second cyclone (7), Venturi tube (8), pre-combustion grade sleeve (9), pre-combustion grade double oil circuits swirl atomizer (10) are constituted, wherein beam hanger (1) and head body (2) It is integrally formed by 3D printing, wherein head body (2) includes head body front end (11) and head body rear end (12), main combustion stage 3D printing is completed together for blade (3) and head body (2), main combustion stage oilhole is provided on each blade axial position, for spraying Fuel oil is penetrated, is blended with air, main combustion stage blade sleeve (4) is covered outside and to be welded, interstage section in main combustion stage blade (3) (5) for pre-combustion grade and main combustion stage flame to be isolated, there is the outer diameter of interstage section (5) screw thread and head body (2) to carry out screw thread company It connects；The internal diameter of interstage section (5) also has screw thread, is attached with pre-combustion grade sleeve (9), pre-combustion grade level-one cyclone (6) and pre- Firing grade second cyclone (7) is radially slotted air admission type cyclone, and the two welds together with Venturi tube (8), and pre-combustion grade two Grade cyclone (7) is welded with pre-combustion grade sleeve (9), so that it is whole to form pre-combustion grade, then with interstage section (5), head body Front end (11) is threadedly coupled, and entire head is constituted.

2. a kind of blade with cooling structure according to claim 1 sprays low emission combustor head, feature exists In: both the beam hanger (1) and head body (2) whole interior possess side-by-side three oil circuits, wherein main combustion stage oil circuit (13) Valid circulation area is between 10mm2-80mm2, and main combustion stage oil enters head body (2) from beam hanger (1), and in head body After circumferentially turning around in front end (11), sprayed into each blade, then by aperture on each blade, pre-combustion grade double oil circuits include Pre-combustion grade working connection (14) and pre-combustion grade auxiliary oil circuit (15), the two are distributed in main combustion stage oil circuit two sides, play the role of thermal protection, Middle pre-combustion grade working connection (14) valid circulation area is between 50 mm2 of 5mm2-, pre-combustion grade auxiliary oil circuit (15) valid circulation area Between 30 mm2 of 1mm2-, the two-way oil stream of pre-combustion grade enters head body (2) through beam hanger (1), in head body front end (11) after being turned around in the circumferential in around main combustion stage oil circuit (13), into head body rear end (12) and enter the double oil of pre-combustion grade Road swirl atomizer (10), is sprayed.

3. a kind of blade with cooling structure according to claim 1 sprays low emission combustor head, feature exists In: in the head body (2), includes one or more heat-insulated cavities (16), play the role of thermal protection to oil circuit.

4. a kind of blade with cooling structure according to claim 1 sprays low emission combustor head, feature exists In: the main combustion stage blade (3), blade number are 12-36, and angle is 15 °-60 °, and vane thickness is 0.8-2mm, Swirling number is 0.5-1.2, and nozzle opening is provided on the axial direction of each blade, and oilhole diameter is 0.2-1.5mm, total flow Number is 60-180 kg/ (hr*Mpa^0.5), and fuel oil and air can be made sufficiently to be blended, the discharge of pollutant is reduced.

5. a kind of blade with cooling structure according to claim 1 sprays low emission combustor head, feature exists In the pre-combustion grade double oil circuits swirl atomizer (10), be threadingly attached to head body (2) center, and with Venturi tube (8) Cooperation, reaches good atomization, combustion efficiency, the small oil circuit nozzle of pre-combustion grade double oil circuits swirl atomizer (10), and flow number is 5- 30 kg/ (hr*Mpa^0.5), big oil circuit nozzle flow number are 10-100 kg/ (hr*Mpa^0.5), the centrifugation of pre-combustion grade double oil circuits It is 30 ° -120 ° that nozzle (10), which sprays mist of oil subtended angle, and it is 20 ° -70 ° that Venturi tube (8), which exports subtended angle,.

6. a kind of blade with cooling structure according to claim 1 sprays low emission combustor head, feature exists In: the outlet subtended angle of pre-combustion grade sleeve (9) is 10 ° -60 °, and subtended angle and Venturi tube (8) subtended angle carry out matched design, makes pre-burning Grade mist of oil state is preferable, and pre-combustion grade flame reaches stability and high efficiency burning.

7. a kind of blade with cooling structure according to claim 1 sprays low emission combustor head, feature exists It is 0.3-1.2 in: pre-combustion grade level-one cyclone (6) swirling number, pre-combustion grade second cyclone (7) swirling number is 0.2-1.2, two Person is the same as rotation or derotation.

8. a kind of blade with cooling structure according to claim 1 sprays low emission combustor head, feature exists In: the ratio between effective area of pre-combustion grade level-one cyclone (6) and pre-combustion grade second cyclone (7) is between 1:8-9:1, pre-burning Grade overall the ratio between effective area and main combustion engine effective area are between 1:4-1:10.

9. a kind of blade with cooling structure according to claim 1 sprays low emission combustor head, feature exists In: cooling hole is provided in interstage section (5) axial direction, number is 10-36, and aperture is 0.5-2mm；It is provided with gas in radial directions Dynamic deflector hole, number are 10-36, and aperture is 0.1-2mm, can be matched with pre-combustion grade sleeve (9) outer diameter, between grade Section recirculating zone is influenced, to play the role of stable flame.