阅读说明：本技术 利用气冷结构匹配点火位置的值班火焰稳定器及设计方法 (On-duty flame stabilizer using air cooling structure to match ignition position and design method ) 是由 范育新 陈玉乾 郭昆 赵世龙 于 2019-11-12 设计创作，主要内容包括：本发明公开了一种利用气冷结构匹配点火位置的值班火焰稳定器及设计方法。值班火焰稳定器包括火焰稳定器主体、离心式喷嘴和点火器。由于在稳定器上开设冷却孔,引外涵冷却气在热侧壁面形成一层薄的气膜,从而实现对稳定器的热防护,可以根据稳定器壁温分布加密局部位置的冷却孔。在稳定器的倒圆角抑制流动分离的发生,有效防止位于稳定器热侧的热燃气通过冷却孔倒流进冷气侧,避免稳定器壁面温度过高而发生烧蚀。本发明利用稳定器上冷却孔的不同开孔方向组合实现对值班火焰稳定器的流场结构进行主动控制,有效地降低稳定器热侧壁面温度,提高稳定器在高温燃气中的寿命。本发明结构简单,提高点火可靠性、火焰稳定性及点火位置布置的自主可控性。(The invention discloses an on-duty flame stabilizer using an air cooling structure to match an ignition position and a design method. The on-duty flame holder includes a flame holder body, a swirler and an igniter. Because the cooling holes are formed in the stabilizer, the outer culvert cooling air is guided to form a thin air film on the wall surface of the hot side, so that the thermal protection of the stabilizer is realized, and the cooling holes in local positions can be encrypted according to the temperature distribution of the wall of the stabilizer. The fillet at the stabilizer restraines the emergence of flowing the separation, effectively prevents to be located the hot gas of stabilizer hot side and advances the cold gas side through the cooling hole refluence, avoids stabilizer wall temperature too high and takes place to ablate. The invention utilizes the combination of different opening directions of the cooling holes on the stabilizer to realize the active control of the flow field structure of the flame stabilizer on duty, effectively reduces the temperature of the wall surface at the hot side of the stabilizer and prolongs the service life of the stabilizer in high-temperature fuel gas. The invention has simple structure, and improves the ignition reliability, the flame stability and the autonomous controllability of the ignition position arrangement.)

1. An on-duty flame stabilizer matched with an ignition position by using an air cooling structure is characterized by comprising a flame stabilizer main body (1), wherein the flame stabilizer main body (1) comprises a front plate (101) extending horizontally, an inclined plate (102) arranged at the rear end of the front plate (101) and extending obliquely upwards, and a rear plate (103) arranged at the rear end of the inclined plate (102) and extending horizontally; a concave cavity (2) is formed below the structure formed by the inclined plate (102) and the rear plate (103); the back plate (103) is provided with a centrifugal nozzle (3) and an igniter (4); rounding (104) at the joint of the sloping plate (102) and the rear plate (103) on the side wall surface of the cold air; the flame stabilizer main body (1) is provided with a plurality of cooling holes as an air cooling structure.

2. The on-duty flame holder matched with ignition position using air cooling structure as claimed in claim 1, wherein the thermal protection means is a plurality of first cooling holes (105) provided on the inclined plate (102) and a plurality of second cooling holes (106) provided on the rear plate (103).

3. The flame stabilizer on duty using air cooling structure to match ignition position of claim 2, wherein the opening angle of the first cooling holes (105) on the tilted plate (102) is α the opening direction of the first cooling holes (105) and the tilted plate, the opening angle of the second cooling holes (106) on the rear plate (103) is β the opening direction of the second cooling holes (106) and the rear plate, and the included angle α and the included angle β are the same or different.

4. The on-duty flame holder using an air-cooled structure to match an ignition position as set forth in claim 2, wherein the plurality of first cooling holes (105) and the plurality of second cooling holes (106) are arranged in a row.

5. The on-duty flame holder for matching ignition position using air cooling structure according to claim 1, wherein the inclined plate (102) is included at an angle θ of 60 ° with the front plate (101).

6. The on-duty flame holder for matching ignition position using air cooling structure according to claim 1, wherein the centrifugal nozzle (3) is a pressure atomizing nozzle and the igniter (4) is a high energy igniter.

7. A design method of an on-duty flame stabilizer using an air cooling structure to match an ignition position is characterized by comprising the following steps:

(a) designing specification parameters of a flame stabilizer main body (1), wherein the specification parameters comprise the lengths of a front plate (101) and a rear plate (103) which form the flame stabilizer main body (1) and the distance between the front plate and the rear plate, and determining an included angle theta between an inclined plate (102) and the front plate (101) or the rear plate (103);

(b) setting an air cooling structure: the inclined plate (102) and the rear plate (103) are subjected to thermal protection in a gas film cooling mode, the arrangement modes of the first cooling holes (105) and the second cooling holes (106) are arranged in rows, the hole diameter and the hole spacing of the cooling holes can be determined according to actual requirements, and the hole opening density of a local area is adjusted according to the temperature distribution conditions of the hot side walls of the inclined plate (102) and the rear plate (103) during stable combustion;

(c) the opening angle of a first cooling hole (105) on the inclined plate (102) is an included angle α between the opening direction and the inclined plate, the opening angle of a second cooling hole (106) on the rear plate (103) is an included angle β between the opening direction and the inclined plate, and the return flow region is controlled by utilizing different combinations of the opening directions of the first cooling hole (105) and the second cooling hole (106), so that the independent control of the optimal ignition position required by the afterburner is realized;

(d) rounding (104) at the joint of the cold air side wall surface inclined plate (102) and the rear plate (103);

(e) the method comprises the steps of selecting a centrifugal nozzle (3) according to actual requirements such as oil supply quantity and an atomization angle of on-duty ignition of an afterburner, selecting an igniter (4) according to the actual ignition energy requirement, and respectively determining the positions of the centrifugal nozzle (3) and the igniter (4) according to a flow field structure controlled by an air cooling structure and a matched ignition position.

Technical Field

The invention relates to the technical field of aviation power propulsion systems, in particular to an on-duty flame stabilizer using an air cooling structure to match an ignition position and a design method.

Background

With the continuous development of modern advanced aero-engine technology, the turbofan engine gradually replaces the earlier developed turbojet engine with the advantages of high economy, good operational performance and the like in a cruising state. In order to ensure that the turbofan afterburner can work stably, the afterburner is required to implement soft ignition, namely ignition is carried out under a very low oil-gas ratio, and the function can be realized by adopting an on-duty flame stabilizer. The large backflow area behind the on-duty flame stabilizer has the function of spreading the flame with stable inside outwards, and the on-duty stabilizer is an effective measure for improving the stable combustion of mixed gas and expanding the stable working range. The currently mainly used on-duty flame stabilizer mainly comprises: v-shaped flame stabilizer, double V-shaped flame stabilizer, film evaporation V-shaped duty stabilizer, special evaporation V-shaped flame stabilizer, evaporation type flame stabilizer, sand dune standing vortex flame stabilizer and the like.

The flame stabilizer on duty is a core component for ensuring stable combustion of the afterburner of the aircraft engine, the service life and the ignition performance of the flame stabilizer are improved, and the working reliability of the turbofan afterburner is ensured. With the development of modern advanced turbofan engines, in order to achieve a larger thrust-weight ratio, the temperature rise of the main combustion chamber is increased, the temperature of the gas in front of the turbine is obviously increased, and the incoming flow speed and temperature entering the afterburner are greatly increased. The increased incoming flow velocity places higher demands on the stability design of the flame stabilizer on duty. The improvement of the incoming flow temperature brings new challenges to the design work of the stabilizer, and in order to ensure that the stabilizer works stably and reliably under the high-temperature condition, the wall surface temperature of the stabilizer must be ensured within the range which can be borne by materials, and the flame stabilizer is prevented from being ablated by high-temperature fuel gas, so that a proper amount of cooling gas needs to be introduced to cool the stabilizer, and the service life of the stabilizer is prolonged.

Disclosure of Invention

The purpose of the invention is as follows: the invention aims to solve the technical problem of providing an on-duty flame stabilizer which utilizes an air cooling structure to match an ignition position, so that the working life and the reliability of the on-duty flame stabilizer under the condition of high-temperature gas are improved, the requirements of a afterburner on different ignition positions under the condition of high-temperature high-speed incoming flow are met, and the wide ignition and stable working range of the on-duty flame stabilizer is ensured. The invention also provides a design method of the flame stabilizer on duty by matching the air cooling structure with the ignition position.

The technical scheme is as follows: in order to achieve the above object, the flame stabilizer on duty using an air cooling structure to match an ignition position according to the present invention includes a flame stabilizer main body, wherein the flame stabilizer main body includes a front plate extending horizontally, an inclined plate disposed at a rear end of the front plate and extending obliquely upward, and a rear plate disposed at a rear end of the inclined plate and extending horizontally; a concave cavity is formed below the structure formed by the inclined plate and the rear plate; the back plate is provided with a centrifugal nozzle and an igniter; rounding off the joint of the inclined plate and the rear plate on the side wall surface of the cold air; the flame stabilizer main body is provided with a plurality of cooling holes as air cooling structures.

The air cooling structure is air film cooling, and the special treatment of the fillet at the corner of the side wall surface of the cold air side of the stabilizer can effectively prevent the ablation of the stabilizer caused by the backflow of high-temperature fuel gas at the hot side into the cold air side through the cooling hole, so the cooling and structural scheme can ensure the service life and the reliability of the stabilizer under the condition of high-temperature fuel gas.

The inclined plate and the rear plate of the flame stabilizer main body form a concave cavity-shaped structure, a high-temperature and high-speed main flow is included to form a low-speed backflow area in the concave cavity, and a high oil-gas ratio can be locally kept in the backflow area under a lean oil state, so that the wide ignition and stable working range of the flame stabilizer on duty is ensured.

The joint of the inclined plate and the rear plate on the outer side wall surface of the flame stabilizer main body, namely the corner, adopts a fillet treatment mode, so that the flow separation of cold airflow of the outer culvert channel at the corner can be inhibited, and the high-temperature fuel gas on the hot side is prevented from flowing back to the cold airflow side through the cooling hole to cause the ablation of the stabilizer.

The air cooling structure comprises a plurality of first cooling holes arranged on the inclined plate and a plurality of second cooling holes arranged on the rear plate.

The opening angle of the first cooling holes on the inclined plate is α the opening direction of the first cooling holes and the inclined plate, the opening angle of the second cooling holes on the rear plate is β the opening direction of the second cooling holes and the rear plate, and the included angle α is the same as or different from the included angle β.

The arrangement modes of the first cooling holes and the second cooling holes are all in a socket arrangement mode, when the on-duty flame stabilizer is stably combusted, the high-temperature area is in the cavity and is subjected to heat transfer and radiation, the inclined plate and the rear plate are high in temperature, the cooling holes are formed in the inclined plate and the rear plate, and the working life and the reliability of the on-duty flame stabilizer under the high-temperature gas condition can be effectively improved due to the socket arrangement.

The included angle between the inclined plate and the front plate is 60 degrees.

The centrifugal nozzle is a pressure atomizing nozzle, and the igniter is a high-energy igniter.

The invention relates to a design method of an on-duty flame stabilizer using an air cooling structure to match an ignition position, which comprises the following steps:

(a) designing specification parameters of the flame stabilizer main body, wherein the specification parameters comprise the length of a front plate and a rear plate (the distance between the front plate and the rear plate) which form the flame stabilizer main body, and determining an included angle theta between an inclined plate and the front plate or the rear plate;

(b) setting an air cooling structure: the inclined plate and the rear plate are thermally protected in a gas film cooling mode, the arrangement modes of the first cooling holes and the second cooling holes are arranged in a row, the aperture and the hole spacing of the cooling holes can be determined according to actual requirements, and meanwhile, the hole opening density of a local area is adjusted according to the temperature distribution condition of the hot side walls of the inclined plate and the rear plate during stable combustion, so that the cooling effect of the whole plate is controlled, and the optimal ignition position required by the afterburner is autonomously controlled;

(c) the opening angle of the first cooling hole on the inclined plate is α the included angle between the opening direction and the inclined plate, the opening angle of the second cooling hole on the rear plate is β the included angle between the opening direction and the inclined plate, and the reflux area is controlled by utilizing different combinations of the opening directions of the first cooling hole and the second cooling hole, so that the independent control of the optimal ignition position required by the afterburner is realized;

(d) rounding off the joint of the inclined plate and the rear plate on the side wall surface of the cold air;

(e) selecting a centrifugal nozzle according to actual requirements of the afterburner on-duty ignition such as oil supply quantity, an atomization angle and the like, selecting an igniter according to the actual ignition energy requirement, and respectively determining the positions of the centrifugal nozzle and the igniter according to a flow field structure controlled by an air cooling structure and a matched ignition position.

Further, in step (e), the swirler is a conventional pressure atomization nozzle, and the igniter is a conventional high-energy igniter;

the positions of the centrifugal nozzle and the igniter can be respectively determined according to the flow field structure and the ignition position matched by the air cooling structure, so that the aims of improving the atomization effect, the combustion efficiency and the ignition performance of the flame stabilizer on duty and widening the ignition range are fulfilled.

The reflux zone is formed in the concave cavity, the structure of the reflux zone is basically not interfered by the flow velocity of the main flow of the inner culvert, the structure, the position and the size of the reflux zone can be actively controlled by the air cooling structure, and the optimal ignition position and the optimal ignition range are matched by the air cooling structure, so the design scheme can meet the requirements of different afterburner structures on the ignition position under the conditions of high temperature and high speed incoming flow. The flame stabilizer on duty adopts a centrifugal nozzle oil supply scheme, and in a lean oil state, a high oil-gas ratio can be locally kept in a backflow region due to a low-speed backflow region in the concave cavity, so that the wide ignition and stable working range of the flame stabilizer on duty can be ensured.

Has the advantages that: (1) according to the on-duty flame stabilizer using the air cooling structure to match the ignition position, the high-temperature wall surface of the stabilizer is cooled by adopting the air film, and the special treatment of chamfering at the corner of the cold air side wall surface of the stabilizer can effectively prevent the high-temperature fuel gas at the hot side from flowing back into the cold air side through the cooling hole to cause ablation of the stabilizer, so that the cooling and structural scheme can ensure the working life and reliability of the stabilizer under the condition of high-temperature fuel gas; (2) the backflow zone is formed in the cavity of the flame stabilizer main body, the structure of the backflow zone is basically not interfered by the flow velocity of the main flow of the connotation, the structure, the position and the size of the backflow zone can be actively controlled by the opening directions of the first cooling hole on the inclined plate and the second cooling hole on the rear plate, and the optimal ignition position and the optimal ignition range are matched by the air-cooled structure, so that the design scheme can meet the requirements of an afterburner on different ignition positions under the conditions of high temperature and high speed incoming flow, and the flame stabilizer with the class number has higher universality on different afterburner structures; (3) the on-duty flame stabilizer adopts the concave cavity of the centrifugal nozzle oil supply scheme, and under the lean state, a high oil-gas ratio can be locally kept in a backflow region due to the low-speed backflow region in the concave cavity, so that the wide ignition and stable working range of the on-duty flame stabilizer can be ensured; the positions of the centrifugal nozzle and the igniter can be respectively determined according to the flow field structure controlled by the air cooling structure and the matched ignition position, so that the aims of improving the atomization effect, the combustion efficiency and the ignition performance of the class-on-duty flame stabilizer and widening the ignition range are fulfilled; (4) the flame stabilizer on duty has the advantages of simple structure, long service life, reliable cooling scheme, autonomously controllable ignition position, good ignition performance, large working range of the stabilizer and the like, and is particularly suitable for afterburners under the working conditions of high temperature and high speed incoming flow.

Drawings

FIG. 1 is a schematic view of an on-duty flame holder of the present invention utilizing an air cooling configuration to match the ignition location;

FIG. 2 is a comparison graph of the front and rear total pressure distribution of the fillet at the joint of the outer wall inclined plate and the rear plate;

FIG. 3 is a comparison of flow field traces for different combinations of cooling hole angles;

FIG. 4 is a schematic diagram of the temperature distribution of the front and rear hot side walls of the airless cooling structure;

FIG. 5 is a schematic diagram of the temperature distribution of the front and rear hot side walls of the gas-filled cold structure.

Detailed Description

The invention provides an on-duty flame stabilizer using an air cooling structure to match an ignition position, and in order to make the purpose, technical scheme and effect of the invention clearer and clearer, the invention is further described in detail by referring to the attached drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.