CN-122014457-A - Boron-based powder fuel bimodal ramjet engine

Abstract

The invention discloses a boron-based powder fuel bimodal ramjet engine which comprises an air inlet component, a combustion chamber, an annular fuel gas generator and a pneumatic choking type powder fuel supply component, wherein the air inlet component is used for introducing and compressing incoming air, an equal straight section of the combustion chamber is axially and fixedly communicated with the rear end of the air inlet component, a first concave cavity and a second concave cavity are sequentially arranged in an injection section along the direction far away from the air inlet component, a plurality of first powder through hole arrays positioned on the front side of the first concave cavity and a plurality of gas through hole arrays positioned between the first concave cavity and the second concave cavity are arranged in the injection section, the annular fuel gas generator is used for conveying rich fuel gas to the injection section through the gas through hole arrays and sleeved on the outer side of the injection section, and the pneumatic choking type powder fuel supply component comprises an annular flow guide channel component and a powder supply component. The device can realize smooth conversion of the sub-combustion mode and the super-combustion mode, stable and controllable conveying of the powder fuel and high mixing and combustion efficiency with the incoming flow.

Inventors

• ZHAO BOYI
• HAN WENXUE
• LI CHAO
• HU CHUNBO
• CUI WEI
• LEI RONG
• DONG JIAXIN

Assignees

• 西北工业大学

Dates

Publication Date

20260512

Application Date

20260205

Claims (6)

1. 1. A boron-based pulverized fuel bimodal ramjet engine, characterized by comprising an air intake assembly (10), a combustion chamber (20), an annular fuel gas generator (30) and a pneumatic choked pulverized fuel supply assembly (40); the air inlet assembly (10) is used for introducing and compressing incoming air; The combustion chamber (20) is provided with an equal straight section (21), an injection section (22) and an expansion section (23) which are integrally connected, the equal straight section (21) is axially fixedly communicated with the rear end of the air inlet assembly (10), a first concave cavity (24) and a second concave cavity (25) are sequentially arranged in the injection section (22) along the direction away from the air inlet assembly (10), the injection section (22) is provided with a plurality of first powder through hole arrays (26) positioned on the front side of the first concave cavity (24) and a plurality of gas through hole arrays (27) positioned between the first concave cavity (24) and the second concave cavity (25), and the plurality of first powder through hole arrays (26) and the plurality of gas through hole arrays (27) are uniformly distributed along the circumferential direction of the injection section (22); The annular fuel gas generator (30) is used for conveying the rich fuel gas to the injection section (22) through the fuel gas through hole array (27), is sleeved outside the injection section (22), and is fixedly connected with the outer side wall of the injection section (22), wherein the front end of the annular fuel gas generator is positioned at the rear side of the first powder through hole array (26) and is positioned at the tail end of the injection section (22); The pneumatic choked powder fuel supply assembly (40) comprises an annular flow guide channel member (41) and a powder supply assembly (42); The annular flow guide channel member (41) is sleeved on the combustion chamber (20) and is used for introducing an incoming flow and dividing the flow into fluidization gas and driving gas to be conveyed to the powder supply assembly (42); The powder supply assembly (42) is sleeved on the annular flow guide channel member (41) and is used for driving the output of the internal boron-based powder fuel by means of driving gas and inputting the internal boron-based powder fuel into the combustion chamber (20) through the first powder through hole array (26), and fluidizing the boron-based powder fuel by means of fluidizing gas in the process of outputting the boron-based powder fuel.
2. 2. The boron-based powder fuel bimodal ramjet engine of claim 1 wherein the annular fuel gas generator (30) comprises a first annular cylindrical hollow housing (31), a second annular cylindrical hollow housing (32), an annular drain recess plate (33), a first annular solid fuel propellant charge (34), a second annular solid fuel propellant charge (35); The first annular cylindrical hollow shell (31) and the second annular cylindrical hollow shell (32) are sleeved on the injection section (22); The opposite sides of the first annular cylindrical hollow shell (31) and the second annular cylindrical hollow shell (32) are both open, the opposite sides are both sealed, and the two end walls of the annular drainage concave plate (33) are respectively and axially fixedly connected with the outer side walls of the first annular cylindrical hollow shell (31) and the second annular cylindrical hollow shell (32); The first annular solid fuel propellant grains (34) are filled and arranged in the first annular cylindrical hollow shell (31), and the second annular solid fuel propellant grains (35) are filled and arranged in the second annular cylindrical hollow shell (32); the gap between the inner walls of the first annular cylindrical hollow shell (31) and the second annular cylindrical hollow shell (32) forms a fuel-rich gas through hole (36), and the gap distance is larger than or equal to the width of the gas through hole array (27) along the axial direction of the engine; The inner sides of the outer walls of the openings of the first annular cylindrical hollow shell (31) and the second annular cylindrical hollow shell (32) are fixedly provided with igniters (37).
3. 3. The boron-based powder fuel bimodal ramjet engine according to claim 2, wherein the annular diversion channel member (41) is provided with a hollow annular shell (411), an annular fixed disc (412) and a first annular supporting disc (413), the first annular supporting disc (413) is integrally connected inside the front end of the hollow annular shell (411), the annular fixed disc (412) is integrally connected to the rear end face of the hollow annular shell (411), the inner wall of the first annular supporting disc (413) is fixedly connected to the part of the equal straight section (21) positioned at the front end of the first powder through hole array (26), and the inner diameters of the annular fixed disc (412) and the first annular supporting disc (413) are smaller than the inner diameter of the inner wall of the hollow annular shell (411) and are equal to the outer diameter of the injection section (22); At least two circles of evenly distributed fluidization air through holes (414) and at least two circles of evenly distributed driving air through holes (415) are formed in the outer wall of the hollow annular shell (411) along the circumferential direction, at least one air inlet hole (416) is formed in the front end of the outer side wall, the fluidization air through holes (414) are formed in the front end of the first concave cavity (24), and the driving air through holes (415) are formed in the rear end of the hollow annular shell (411); The front part of the hollow annular shell (411) positioned at the fluidization gas through hole (414) penetrates through the inner wall and the outer wall and is provided with a second powder through hole array (417), the second powder through hole array (417) of the inner wall of the hollow annular shell (411) is communicated with the second powder through hole array (417) of the outer wall in a sealing way through an arc-shaped communication plate (420), and the projection of each through hole of the second powder through hole array (417) on the outer side wall of the combustion chamber (20) along the radial direction of the hollow annular shell (411) is overlapped with each through hole of the second powder through hole array (417); The inside vertical fixedly connected with of cavity annular casing (411) is the same and internal diameter with equal straight section (21) first annular baffle (418) and second annular baffle (419) that the internal diameter is equal, first annular baffle (418) and second annular baffle (419) are located respectively first powder through-hole array (26) are followed equal straight section (21) axial both sides.
4. 4. A boron-based powder fuel bimodal ramjet engine according to claim 3, characterized in that the powder supply assembly (42) comprises a hollow annular powder tank (421), a fluidization cone (422), a fluidization disc (423), an annular piston (424) and an annular adjustment sleeve (425); The front end face of the hollow annular powder storage tank (421) is in an opening shape, the rear end face of the hollow annular powder storage tank (421) is in a sealing shape, the front end face of the hollow annular powder storage tank (421) is positioned at the rear side of the fluidization gas through hole (414) along the axial direction of the combustion chamber (20), and the rear end face is fixedly assembled with the annular fixed disc (412); The large opening sides of the fluidization cone (422) and the fluidization disc (423) face the hollow annular powder storage tank (421); The annular adjusting sleeve (425) is arranged at the front side of the second powder through hole array (417) along the axial direction of the combustion chamber (20) and is fixedly sleeved on the hollow annular shell (411); The front end of the fluidization disc (423) is positioned between the second powder through hole array (417) and the fluidization air through hole (414) and sleeved on the hollow annular shell (411), and the rear end of the fluidization disc (423) is fixedly connected with the front end surface of the hollow annular powder storage tank (421) in an axial direction; the front end of the fluidization cone (422) is fixedly sleeved on the annular adjusting sleeve (425), and the rear end of the fluidization cone is axially and fixedly connected with the front end surface of the hollow annular powder storage tank (421); the annular piston (424) is arranged inside the hollow annular powder storage tank (421), the outer side wall of the annular piston is in contact with the inner side of the outer side wall of the hollow annular powder storage tank (421), the inner side wall of the annular piston is in contact with the inner side of the inner side wall of the hollow annular powder storage tank (421), and the annular piston can slide towards the fluidization disc (423) along the axial direction of the hollow annular powder storage tank (421) under the action of driving gas.
5. 5. The boron-based powder fuel bimodal ramjet engine of claim 4, wherein the annular adjustment sleeve (425) comprises a second annular support disc (4251) and an annular sealing plate (4252), the second annular support disc (4251) is fixedly sleeved on the hollow annular shell (411), the front end of the annular sealing plate (4252) is integrally sleeved on the second annular support disc (4251), and a cavity formed between the annular sealing plate (4252) and the hollow annular shell (411) is a powder flow adjustment cavity (4253); A third annular supporting disc (4254) is vertically and fixedly connected to the inner side of the inner wall of the hollow annular powder storage tank (421), the third annular supporting disc (4254) is positioned at the rear side of the driving air through hole (415) along the axial direction of the combustion chamber (20), and a cavity formed between the inner wall of the hollow annular powder storage tank (421) and the hollow annular shell (411) is an annular flow guiding adjusting cavity (4255); A first annular adjusting plate (4256) capable of axially sliding along the hollow annular shell (411) is arranged in the powder flow adjusting cavity (4253), and the first annular adjusting plate (4256) is sleeved on the hollow annular shell (411) and is used for adjusting the overall opening of the second powder through hole array (417); The annular flow guide adjusting cavity (4255) is internally provided with a second annular adjusting plate (4257) and a third annular adjusting plate (4258) which can axially slide along the hollow annular shell (411), the second annular adjusting plate (4257) and the third annular adjusting plate (4258) are sleeved on the hollow annular shell (411), and the second annular adjusting plate (4257) is close to the fluidization disc (423); the second annular adjusting plate (4257) is used for adjusting the opening circle number of the fluidization air through hole (414), and the third annular adjusting plate (4258) is used for adjusting the opening circle number of the driving air through hole (415).
6. 6. The boron-based powder fuel bimodal ramjet engine according to claim 5, wherein the air intake assembly (10) comprises an air intake pipe (11) and a flow guide cone (12), the rear end of the air intake pipe (11) being in fixed communication with the front end of the equal straight section (21); the front end of the guide cone (12) extends out of the air inlet pipe (11), the middle part of the guide cone is fixedly connected with the inner wall of the front end of the air inlet pipe (11) through ribs (13) circumferentially assembled on the outer wall of the guide cone, the tail end of the guide cone is positioned at the tail part of the air inlet pipe (11), and an air inlet channel is formed by a hole between the air inlet pipe (11) and the guide cone (12).

Description

Boron-based powder fuel bimodal ramjet engine Technical Field The invention relates to the technical field of ramjet engines, in particular to a boron-based powder fuel bimodal ramjet engine. Background The ramjet engine is taken as an important component of the suction type propulsion system, and is considered as an ideal power device for realizing hypersonic flight due to the advantages of simple structure, high specific impulse, capability of working in a wide Mach number range and the like. In particular to a Dual-mode scramjet engine (Dual-Mode Scramjet, DMSJ), which can realize subsonic combustion and supersonic combustion in the same engine, can realize the advantages of the subsamjet engine and the scramjet engine, and can realize subsonic combustion in a combustion chamber when the flight Mach number of the engine is 3-6 and supersonic combustion in the combustion chamber when the flight Mach number is more than 6. Therefore, a bimodal ramjet engine (Dual-Mode Scramjet) capable of autonomously switching between the two modes of sub-combustion and super-combustion according to the incoming flow conditions has become a hot spot of current research. In the prior art, a dual-mode scramjet engine mostly adopts liquid hydrocarbon fuel or hydrogen fuel. In addition, the liquid fuel has the problems of dissociation of hydrocarbon fuel combustion products, poor combustion stability, limited engine specific impulse and the like under high Mach number flight. Hydrogen has excellent reactivity and wide flammability limit, but has low density, inconvenient storage and transportation, potential safety hazard and limited application. In order to improve the working performance of the dual-mode scramjet engine under the wide Mach number, boron-based powder fuel with higher heat value is applied to the field of the dual-mode scramjet engine. The boron-based powder fuel dual-mode scramjet engine adopts boron-based powder fuel with high heat value, stable storage and good safety as fuel, can remarkably improve the specific impact performance of the scramjet engine, has higher total incoming flow temperature when working under high Mach number, is not easy to dissociate the combustion products of the powder fuel, and can fully release the chemical energy of the fuel. However, when boron-based powder fuel is applied to a dual-mode scramjet engine, the difficulty of mode-to-mode conversion is high, and stable and controllable continuous conveying of powder is difficult to realize under a back pressure environment with wide range variation. In addition, the powder fuel has large inertia and low mixing efficiency with high-speed inflow, and the residence time of the powder fuel in supersonic airflow is extremely short, so that the problems of difficult ignition, unstable combustion, low efficiency and the like are caused. Especially at low speed, the total temperature of the incoming flow is low, and the blending combustion is more difficult. Disclosure of Invention Based on the above, it is necessary to provide a boron-based powder fuel bimodal ramjet engine, which can realize smooth transition between a sub-combustion mode and an overfire mode, stably and controllably convey powder fuel, and has high combustion efficiency in mixing with an incoming flow. The invention provides a boron-based powder fuel bimodal ramjet engine, which comprises an air inlet assembly, a combustion chamber, an annular fuel gas generator and a pneumatic choking type powder fuel supply assembly, wherein the air inlet assembly is connected with the annular fuel gas generator; the air inlet assembly is used for introducing and compressing incoming air; the combustion chamber is provided with an equal straight section, an injection section and an expansion section which are integrally connected, the equal straight section is axially and fixedly communicated with the rear end of the air inlet assembly, a first concave cavity and a second concave cavity are sequentially formed in the injection section along the direction away from the air inlet assembly, a plurality of first powder through hole arrays positioned on the front side of the first concave cavity and a plurality of gas through hole arrays positioned in the middle of the first concave cavity and the second concave cavity are formed in the injection section, and the plurality of first powder through hole arrays and the plurality of gas through hole arrays are uniformly distributed along the circumferential direction of the injection section; The annular fuel gas generator is used for conveying the rich fuel gas to the injection section through the gas through hole array, is sleeved on the outer side of the injection section, and is fixedly connected with the outer side wall of the injection section, wherein the front end of the annular fuel gas generator is positioned at the rear side of the first powder through hole array, and the rear end of the annular fuel gas generator is positioned at