Main fuel grade fuel nozzle with continuously adjustable fuel spray hole outlet area and adjusting methodTechnical Field
The invention belongs to the technical field of aero-engines, and particularly relates to a main combustion stage fuel nozzle with a continuously adjustable fuel nozzle orifice outlet area and an adjusting method.
Background
Among the design techniques of the combustion chamber of the aero-engine, the lean premixed pre-evaporation (Lean Premixed Prevaporized, LPP) combustion technique is a design mode with better development prospect at present, can obviously reduce the pollutant emissions such as NOx and the like, and improves the low-pollution emission performance of the combustion chamber. The head of the next generation low pollution combustion chamber adopts lean oil premixing pre-evaporation and graded partition combustion coupling design, a part of premixed part diffusion flame is formed by adopting a swirler, a centrifugal nozzle and a prefilming nozzle in a central precombustion stage area, a main combustion stage and a precombustion stage are concentrically arranged in a surrounding manner, the swirler and the direct injection nozzle in the main combustion stage area form a pre-mixing and evaporation oil-gas mixture, and the pre-mixed flame enters a flame tube combustion area to form premixed flame. Under the large working condition, most of fuel is sprayed out through the main combustion stage, so that the combustion area is mainly made of premixed flame with lower temperature, and the generation and emission of pollutants such as NOx, CO and the like can be obviously reduced.
However, under different working conditions, the air inlet flow, the air inlet speed and the turbulence degree of the air of the main combustion stage cyclone are changed, and the fuel flow matched with the air of the main combustion stage is also adjusted, so that the pre-mixing and pre-evaporating effects of the fuel are possibly inconsistent under different working conditions. For example, under a large working condition, the fuel injection momentum is large, the rotational flow air flow speed is high, the fuel atomization evaporation effect is too good, and the main combustion stage backfire problem can be caused; under the small working condition, the fuel injection momentum is small, the rotational flow air flow speed is small, the fuel atomization evaporation effect is poor, and uneven oil gas distribution at the outlet of the main combustion stage can be caused, so that the problems of hot spots formed in the combustion chamber and exceeding of NOx emission are caused.
The Chinese patent literature database discloses a low-pollution combustion chamber of a limited responsibility company of a Chinese aero-engine and a patent of a combustion control method thereof, the application number is 201810698522.1, the technical scheme refers to the solution of the low-pollution combustion chamber TAPS (Twin Annual Premixing Swirler), a plurality of pre-membrane plates are arranged in a main combustion stage channel, and direct fuel with different intensities is sprayed onto the pre-membrane plates under different working conditions to promote the fuel to be uniformly distributed. According to the technical scheme, reasonable distribution of fuel oil can be realized under different fuel oil flows, however, the pre-membrane plate enables the morphology of the fuel oil liquid column to be changed, and the difficulty of oil-gas organization is improved; moreover, although it is required that both fuel injection points operate at a small flow rate, one of the fuel injection points cannot operate effectively due to the high height of the pre-film plate. Therefore, the fuel injection ignition oil structure of the technical scheme is passive, the main combustion stage small-flow oil-gas mixing is possibly uneven, and the main combustion stage high-efficiency and rapid oil-gas mixing in a wide working condition range is difficult to realize.
Currently, there is a need to develop a main fuel stage fuel nozzle with continuously adjustable fuel nozzle orifice outlet area and an adjusting method.
Disclosure of Invention
The invention aims to provide a main fuel grade fuel nozzle with a continuously adjustable fuel spray hole outlet area, and the other technical problem to be solved is to provide a method for adjusting the main fuel grade fuel nozzle with the continuously adjustable fuel spray hole outlet area, which is used for overcoming the defects of the prior art.
The main fuel level fuel nozzle with the continuously adjustable fuel spray hole outlet area comprises a duty level fuel nozzle, a cyclone and a main fuel level fuel nozzle which are sleeved with one another from inside to outside in sequence along the same central axis, and the outlet of the main fuel level fuel nozzle is sleeved with a sleeve;
The fuel jet flow of the class-value fuel nozzle is unchanged, the cyclone rotates around the class-value fuel nozzle, the fuel jet flow of the main fuel nozzle is regulated, and then the total fuel jet flow of the main fuel nozzle with the continuously adjustable fuel jet orifice outlet area is changed.
Further, the duty grade fuel nozzle is a centrifugal nozzle or a prefilming nozzle;
oil supply pipeline of the class fuel nozzle and oil supply nozzle with fixed value on central axis of the class fuel nozzle; the oil supply pipeline of the class-on-duty fuel nozzle and the swirl vanes of the class-on-duty fuel nozzle circumferentially surround a plurality of central symmetry; the swirl blades of the class-on-duty fuel nozzle are single-stage axial swirl blades or multi-stage swirl blades, and the swirl blades of the class-on-duty fuel nozzle are communicated with the air inlet channel; the outlet of the class-valued fuel nozzle is an outlet venturi of the class-valued fuel nozzle;
The on-duty fuel nozzle supplies fuel through a fuel supply pipeline of the on-duty fuel nozzle and the fuel supply nozzle, atomizes the fuel through a swirl vane of the on-duty fuel nozzle, and forms a fuel jet of the on-duty fuel nozzle through an outlet venturi of the on-duty fuel nozzle.
Further, the main combustion grade fuel nozzle is a cylinder, and is sleeved and fixed on the swirl vane of the duty grade fuel nozzle; the front end of the main combustion stage fuel nozzle extends into an outlet venturi of the duty stage fuel nozzle;
A fuel supply pipeline of the main fuel nozzle perpendicular to the central axis is fixed on the main fuel nozzle; an annular cavity is arranged in the main combustion stage fuel nozzle, and the annular cavity forms an oil supply annular channel of the main combustion stage fuel nozzle; the oil supply pipeline of the main fuel grade fuel nozzle is communicated with the oil supply annular channel of the main fuel grade fuel nozzle sequentially through the oil supply pipeline connecting section of the main fuel grade fuel nozzle and the arc-shaped oil supply pipeline connecting channel of the main fuel grade fuel nozzle;
A plurality of main fuel level fuel nozzle oil supply ports which are uniformly distributed along the circumferential direction are formed on the outer wall surface of the main fuel level fuel nozzle; the oil supply port of the main combustion stage fuel nozzle is a water drop hole; the large end of the oil supply port of the main combustion grade fuel nozzle is the front end, the large end is close to the swirl vane of the valve class fuel nozzle, and the aperture range of the large end is 0.4 mm-0.6 mm; the small end of the oil supply port of the main combustion grade fuel nozzle is a rear end, the small end is close to an outlet venturi of the valve class fuel nozzle, and the small end has a pore diameter ranging from 0.1mm to 0.3mm; an included angle is formed between the symmetrical center line of the oil supply port of the main combustion stage fuel nozzle and the central axis.
Further, the cyclone is a double-layer cylinder and is sleeved on the outer wall surface of the main combustion stage fuel nozzle, and the cyclone is in sliding connection with the main combustion stage fuel nozzle; the inner layer of the cyclone is the inner wall surface of the cyclone, and the outer layer of the cyclone is the outer wall surface of the cyclone;
A plurality of centrally symmetrical cyclone blades are fixed between the inner wall surface of the cyclone and the outer wall surface of the cyclone along the circumferential direction;
The inner wall surface of the cyclone is provided with cyclone nozzle oil supply ports which are in one-to-one correspondence with the oil supply ports of the main combustion stage fuel nozzles, and the cyclone nozzle oil supply ports are positioned between the cyclone blades;
the outer layer of the cyclone is a cyclone outer wall surface, and a cyclone deflector rod vertical to the central axis is fixed on the cyclone outer wall surface; arc-shaped tooth plates are welded and fixed at the top end of the cyclone deflector rod, the arc-shaped tooth plates are meshed with gears of the control motor and the gears, and the control motor of the control motor and the gears drives the arc-shaped tooth plates to perform circumferential movement through the gears of the control motor and the gears so as to drive the cyclone to perform circumferential rotation; the arc-shaped tooth plates limit the swirler to rotate between a preset rotation angle I and a preset rotation angle II, in the rotation process, an oil supply port of the swirler nozzle and an oil supply port of the main fuel nozzle are gradually staggered, three points a, b and c are sequentially reached, and the fuel jet flow rates of the main fuel nozzle are respectively corresponding to the large, medium and small main fuel nozzles.
Further, the inner wall surface of the cyclone is sealed with the outer wall surface of the main combustion stage fuel nozzle, so that oil leakage is avoided after the oil supply port of the cyclone nozzle is in butt joint with the oil supply port of the main combustion stage fuel nozzle.
Further, the number of the oil supply ports of the cyclone nozzle is an integral multiple or half of that of the cyclone blades.
Further, the seal comprises an O-ring seal.
The invention relates to a method for adjusting a main fuel stage fuel nozzle with continuously adjustable fuel spray hole outlet area, which comprises a main fuel stage large-flow working state, a main fuel stage medium-flow working state and a main fuel stage small-flow working state;
main combustion stage high flow operating state:
The class-of-values fuel nozzle works, and the fuel jet of the class-of-values fuel nozzle is provided; when the engine is at cruising speed or cruising altitude, the air inlet flow is large, and the main fuel level fuel nozzle is required to jet large fuel flow according to the working state requirement; the fuel nozzle fuel supply port of the cyclone nozzle is communicated with the main fuel stage fuel nozzle fuel supply port in an aligned mode, the section of a fuel outlet at the point a is a front big and rear small water drop type, fuel is sprayed out from the point a to form a big fuel jet of the main fuel stage fuel nozzle, the big fuel jet is crushed and atomized under the action of cyclone airflow at the outlet of the cyclone blade, and is mixed with the cyclone airflow to form a uniform oil-gas mixture, and the uniform oil-gas mixture enters a combustion chamber for combustion;
flow operating state in main combustion stage:
The class-of-values fuel nozzle works, and the fuel jet of the class-of-values fuel nozzle is provided; when the rotation speed of the engine is low or the working height is increased, and the air inlet flow is reduced, the fuel jet of the main fuel level fuel nozzle needs to be reduced according to the working state requirement; the control motor of the control motor and the gear drives the arc-shaped tooth plates to perform circumferential movement through the gear of the control motor and the gear, so that the cyclone is driven to perform circumferential rotation, an oil supply port of the cyclone nozzle and an oil supply port of the main fuel level fuel nozzle are gradually dislocated, the point b is reached, the section of a fuel outlet of the point b is diamond-shaped, fuel is sprayed out from the point b to form a middle fuel jet of the main fuel level fuel nozzle, the diameter of a middle fuel jet column is reduced, the momentum is increased, the penetration depth is increased, the crushing and atomization effects of the fuel jet column under the middle flow are improved, the middle fuel jet is crushed and atomized under the action of cyclone airflow at the outlet of the cyclone blade, and is mixed with the cyclone airflow to form uniform oil-gas mixture, and the uniform oil-gas mixture enters a combustion chamber for combustion;
main combustion stage small flow operating state:
The class-of-values fuel nozzle works, and the fuel jet of the class-of-values fuel nozzle is provided; when the rotation speed of the engine further becomes lower or the working height continues to rise, and the air inlet flow is further reduced, the fuel jet of the main fuel grade fuel nozzle needs to be continuously reduced according to the working state requirement; the control motor for controlling the motor and the gear continuously drives the arc-shaped tooth plates to perform circumferential movement through the gear for controlling the motor and the gear, so that the cyclone is driven to continuously perform circumferential rotation, an oil supply port of a cyclone nozzle and an oil supply port of a main fuel level fuel nozzle are further staggered to reach a point c, the section of a fuel outlet of the point c is a front small and rear large water drop, fuel is sprayed out of the point c to form a small fuel jet of the main fuel level fuel nozzle, the diameter of a small fuel jet column is continuously reduced, the momentum is continuously increased, the penetration depth is continuously increased, the crushing and atomization effects of the fuel jet column under the small flow are sufficiently improved, the small fuel jet is crushed and atomized under the action of cyclone airflow at the outlet of the cyclone blade, and is mixed with the cyclone airflow to form a uniform oil-gas mixture, and the uniform oil-gas mixture enters a combustion chamber for combustion; the combustion chamber can be in an ideal working state under the condition of low flow, the formation of hot spots at the outlet of the combustion chamber and the generation of pollutants are reduced, and the stability of the combustion chamber is improved.
According to the main fuel level fuel nozzle with the continuously adjustable fuel nozzle outlet area and the adjusting method, according to the fuel flow and air inlet flow requirements, the motor gear is controlled to drive the deflector rod to perform circumferential movement, and then the oil supply port of the cyclone nozzle is driven to perform circumferential movement, so that the continuous change of the oil outlet area of the main fuel level fuel nozzle is realized, the purpose of adjusting and controlling the intensity of a fuel jet column is achieved, the fuel flow and the air inlet flow are matched, the efficient injection of fuel can be ensured under different working conditions, the uniform atomization and evaporation mixing of the fuel jet of the main fuel level fuel nozzle is ensured, the combustion temperature of a main combustion area is controlled, the pollutant emission of a combustion chamber is reduced, and the combustion efficiency and the combustion stability of the combustion chamber are realized.
Drawings
FIG. 1 is a schematic view (perspective view) of a main fuel stage fuel nozzle with continuously adjustable fuel nozzle orifice outlet area according to the present invention;
FIG. 2 is a left side view of FIG. 1;
FIG. 3 is a cross-sectional view A-A of FIG. 2;
FIG. 4 is a schematic view (perspective view) of a main stage fuel nozzle fuel supply port of a main stage fuel nozzle with continuously adjustable fuel nozzle orifice outlet area according to the present invention;
FIG. 5 is a schematic view (perspective view) of a swirler nozzle fuel supply port in a main fuel stage fuel nozzle with continuously adjustable fuel orifice outlet area according to the present invention;
FIG. 6 is a schematic view (partially enlarged view) showing three communication conditions of a swirler nozzle fuel supply port in a main fuel stage fuel nozzle with continuously adjustable fuel injection hole outlet area according to the present invention.
In the figure, 1. An on-duty fuel nozzle; 2. a main fuel stage fuel nozzle; 3. a cyclone; 4. a sleeve;
11. oil supply pipeline of class-valued fuel nozzle and oil supply nozzle; 12. swirl vanes of a class-valued fuel nozzle; 13. an outlet venturi of the duty grade fuel nozzle;
21. An oil supply pipeline of the main fuel grade fuel nozzle; 22. an oil supply pipeline connecting section of the main fuel grade fuel nozzle; 23. an arc-shaped connecting channel of an oil supply pipeline of the main fuel grade fuel nozzle; 24. an oil supply annular channel of the main fuel grade fuel nozzle; 25. a main fuel stage fuel nozzle fuel supply port;
31. controlling a motor and a gear; 32. arc tooth plates; 33. a cyclone deflector rod; 34. the outer wall surface of the cyclone; 35. a cyclone nozzle oil supply port; 36. the inner wall surface of the cyclone; 37. cyclone vanes.
Detailed Description
The invention is described in detail below with reference to the drawings and examples.
Examples: as shown in fig. 1-5, the main fuel stage fuel nozzle with the continuously adjustable outlet area of the fuel spray hole in the embodiment comprises a duty stage fuel nozzle 1, a cyclone 3 and a main fuel stage fuel nozzle 2 which are sleeved in sequence from inside to outside with the same central axis, and an outlet sleeve 4 of the main fuel stage fuel nozzle 2 is sleeved;
The fuel jet flow of the class-value fuel nozzle 1 is unchanged, the cyclone 3 rotates around the class-value fuel nozzle 1, the fuel jet flow of the main fuel stage fuel nozzle 2 is regulated, and then the total fuel jet flow of the main fuel stage fuel nozzle with a continuously adjustable fuel jet orifice outlet area is changed.
Further, the duty grade fuel nozzle 1 is a centrifugal nozzle or a prefilming nozzle;
an oil supply line of the class fuel nozzle 1 and an oil supply nozzle 11 fixed in value on the central axis of the class fuel nozzle; the oil supply pipeline of the class-on-duty fuel nozzle and the swirl vanes 12 of the class-on-duty fuel nozzle, which are symmetrical around a plurality of centers, of the oil supply nozzle 11 are arranged in the circumferential direction; the swirl vanes 12 of the class-on-duty fuel nozzle are single-stage axial swirl vanes or multi-stage swirl vanes, and the swirl vanes 12 of the class-on-duty fuel nozzle are communicated with the air inlet channel; the outlet of the duty fuel nozzle 1 is an outlet venturi 13 of the duty fuel nozzle;
The pilot fuel nozzle 1 supplies fuel through the fuel supply line of the pilot fuel nozzle and the fuel supply nozzle 11, atomizes the fuel through the swirl vanes 12 of the pilot fuel nozzle, and forms a fuel jet of the pilot fuel nozzle 1 through the outlet venturi 13 of the pilot fuel nozzle.
Further, the main fuel level fuel nozzle 2 is a cylinder, and is sleeved and fixed on the swirl vane 12 of the duty level fuel nozzle 1; the front end of the main combustion stage fuel nozzle 2 extends into an outlet venturi 13 of the duty stage fuel nozzle;
A main fuel nozzle fuel supply pipe 21 perpendicular to the central axis is fixed to the main fuel nozzle 2; an annular cavity is arranged in the main combustion stage fuel nozzle 2, and the annular cavity forms an oil supply annular channel 24 of the main combustion stage fuel nozzle; the oil supply pipeline 21 of the main fuel grade fuel nozzle is communicated with the oil supply annular channel 24 of the main fuel grade fuel nozzle sequentially through the oil supply pipeline connecting section 22 of the main fuel grade fuel nozzle and the oil supply pipeline arc-shaped connecting channel 23 of the main fuel grade fuel nozzle;
A plurality of main fuel level fuel nozzle oil supply ports 25 which are uniformly distributed along the circumferential direction are formed on the outer wall surface of the main fuel level fuel nozzle 2; the oil supply port 25 of the main combustion stage fuel nozzle is a water drop hole; the large end of the fuel supply port 25 of the main combustion grade fuel nozzle is the front end, the large end is close to the swirl vane 12 of the pilot grade fuel nozzle, and the hole diameter range of the large end is 0.4 mm-0.6 mm; the small end of the fuel supply port 25 of the main combustion grade fuel nozzle is a rear end, the small end is close to the outlet venturi 13 of the pilot grade fuel nozzle, and the small end has a pore diameter range of 0.1 mm-0.3 mm; an included angle is formed between the symmetrical center line of the fuel supply port 25 of the main fuel grade fuel nozzle and the central axis.
Further, the cyclone 3 is a double-layer cylinder and is sleeved on the outer wall surface of the main combustion stage fuel nozzle 2, and the cyclone 3 is in sliding connection with the main combustion stage fuel nozzle 2; the inner layer of the cyclone 3 is a cyclone inner wall surface 36, and the outer layer of the cyclone 3 is a cyclone outer wall surface 34;
A plurality of centrally symmetrical cyclone blades 37 are fixed between the inner wall surface 36 and the outer wall surface 34 of the cyclone along the circumferential direction;
A cyclone nozzle oil supply port 35 which is in one-to-one correspondence with the main fuel level fuel nozzle oil supply ports 25 is arranged on the inner wall surface 36 of the cyclone, and the cyclone nozzle oil supply ports 35 are positioned between the cyclone blades 37;
The outer layer of the cyclone 3 is a cyclone outer wall surface 34, and a cyclone deflector rod 33 vertical to the central axis is fixed on the cyclone outer wall surface 34; the arc-shaped tooth piece 32 is welded and fixed at the top end of the cyclone deflector rod 33, the arc-shaped tooth piece 32 is meshed with a control motor and a gear of the gear 31, and the control motor of the control motor and the gear 31 drives the arc-shaped tooth piece 32 to perform circumferential movement through the control motor and the gear of the gear 31 so as to drive the cyclone 3 to perform circumferential rotation; the arc-shaped tooth plates 32 limit the swirler 3 to rotate between a preset rotation angle I to a preset rotation angle II, and in the rotation process, the swirler nozzle oil supply port 35 and the main fuel level fuel nozzle oil supply port 25 are gradually staggered to sequentially reach three points a, b and c, and the three points correspond to the fuel jet flow of the large, medium and small main fuel level fuel nozzles 2 respectively.
Further, the inner wall surface 36 of the cyclone is sealed with the outer wall surface of the main fuel level fuel nozzle 2, so that oil leakage is avoided after the oil supply port 35 of the cyclone nozzle is in butt joint with the oil supply port 25 of the main fuel level fuel nozzle.
Further, the number of the cyclone nozzle oil supply ports 35 is an integer multiple or half of the number of the cyclone vanes 37.
Further, the seal comprises an O-ring seal.
As shown in fig. 6, the method for adjusting the fuel nozzle of the main combustion stage with the continuously adjustable outlet area of the fuel nozzle in this embodiment includes a main combustion stage large flow operating state, a main combustion stage medium flow operating state, and a main combustion stage small flow operating state;
main combustion stage high flow operating state:
the class-of-values fuel nozzle 1 works with a fuel jet of the class-of-values fuel nozzle 1; when the engine is at cruising speed or cruising altitude, the air inlet flow is large, and the main fuel level fuel nozzle 2 is required to jet large fuel flow according to the working state requirement; the fuel nozzle fuel supply port 35 of the cyclone nozzle is communicated with the fuel nozzle fuel supply port 25 of the main combustion stage, the fuel outlet section at the point a is in the form of water drops with big front and small back, the fuel is sprayed out from the point a to form large fuel jet flow of the main combustion stage fuel nozzle 2, the large fuel jet flow is crushed and atomized under the action of cyclone airflow at the outlet of the cyclone blade 37, and is mixed with the cyclone airflow to form a uniform oil-gas mixture, and the uniform oil-gas mixture enters a combustion chamber for combustion;
flow operating state in main combustion stage:
The class-of-values fuel nozzle 1 works with a fuel jet of the class-of-values fuel nozzle 1; when the engine speed becomes lower or the working height is increased, and the air inflow is reduced, the fuel jet of the main fuel level fuel nozzle 2 needs to be reduced according to the working state requirement; the control motor of the control motor and the gear 31 drives the arc-shaped tooth piece 32 to perform circumferential movement through the gear of the control motor and the gear 31, so that the cyclone 3 is driven to perform circumferential rotation, the cyclone nozzle oil supply port 35 and the main combustion stage oil nozzle oil supply port 25 are gradually dislocated to reach the point b, the section of the oil outlet of the point b is diamond-shaped, the oil is sprayed out from the point b to form a middle oil jet of the main combustion stage oil nozzle 2, the diameter of a middle oil jet column is reduced, the momentum is increased, the penetration depth is increased, the crushing and atomization effects of the oil jet column under the middle flow are improved, the middle oil jet is crushed and atomized under the action of the cyclone airflow at the outlet of the cyclone blade 37, and is mixed with the cyclone airflow to form a uniform oil-gas mixture, and the uniform oil-gas mixture enters the combustion chamber for combustion;
main combustion stage small flow operating state:
The class-of-values fuel nozzle 1 works with a fuel jet of the class-of-values fuel nozzle 1; when the engine speed further becomes lower or the working height continues to rise, and the air inlet flow is further reduced, the fuel jet of the main fuel grade fuel nozzle 2 needs to be continuously reduced according to the working state requirement; the control motor of the control motor and the gear 31 continuously drives the arc-shaped tooth piece 32 to perform circumferential movement through the gear of the control motor and the gear 31, so that the cyclone 3 is driven to continuously perform circumferential rotation, the cyclone nozzle oil supply port 35 and the main combustion stage oil nozzle oil supply port 25 are further staggered to reach the point c, the section of the oil outlet of the point c is a water drop with small front and large back, the oil is sprayed out of the point c to form a small oil jet of the main combustion stage oil nozzle 2, the diameter of a small oil jet column is continuously reduced, the momentum is continuously increased, the penetration depth is continuously increased, the crushing and atomization effects of the oil jet column under the small flow are sufficiently improved, the small oil jet is crushed and atomized under the action of the swirling airflow at the outlet of the cyclone blade 37, and is mixed with the swirling airflow to form a uniform oil-gas mixture, and the uniform oil-gas mixture enters the combustion chamber for combustion; the combustion chamber can be in an ideal working state under the condition of low flow, the formation of hot spots at the outlet of the combustion chamber and the generation of pollutants are reduced, and the stability of the combustion chamber is improved.
Although embodiments of the invention have been disclosed in the foregoing description and illustrated in the drawings, it will be understood by those skilled in the art that the present invention is not limited to the specific details and illustrations of features and steps set forth herein, and that all features of the invention disclosed, or steps of the method or process, except for mutually exclusive features and/or steps, may be combined in any manner without departing from the principles of the invention.