Powder particle reinforced mixing device for supersonic combustion chamber

Abstract

The invention discloses a powder particle reinforced mixing device for a supersonic combustion chamber. The powder particle reinforced mixing device comprises a partially-covered concave cavity structure and a gas collecting chamber used for spraying combustible gas into the partially-covered concave cavity structure. A first baffle plate and a second baffle plate are partially covered in the concave cavity structure; the first baffle is arranged above the flow inlet, and the second baffle is arranged below the flow inlet. The first baffle and / or the second baffle are horizontally arranged, or one end far away from the flow inlet inclines towards the outer side of the vertical direction partially covering the concave cavity structure. A first powder fuel and fluidizing gas two-phase flow injection hole is formed in the position, located over the first baffle, of the top of the first shell section, and a second powder fuel and fluidizing gas two-phase flow injection hole is formed in the position, located under the second baffle, of the bottom of the second shell section. The gas burner has the characteristics that the residence time of powder particles in the partially-covered cavity structure is long, and the temperature in the cavity structure can be increased through self-sustaining combustion of the combustible gas, so that the powder particles have higher combustion efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of scramjet engines, and particularly to a powder particle enhanced mixing device for a supersonic combustion chamber. Background Art

[0002] A scramjet engine is a ramjet engine in which fuel burns in a supersonic airflow, and has the characteristics of simple structure and high specific impulse performance. A supersonic combustion chamber is the core component of a scramjet engine. After the high-speed airflow is decelerated and pressurized by a constant cross-section isolation section, it enters the combustion chamber at supersonic speed. At the same time, fuel enters the combustion chamber, and within an extremely short millisecond-level time, a series of processes such as fuel-air mixing, ignition, and combustion occur. The high-temperature and high-pressure gas generated by combustion is expanded and accelerated through the expansion section and discharged to generate thrust to propel the aircraft forward.

[0003] A powder scramjet engine is a scramjet engine that uses solid powder fuel. The powder fuel represented by boron and aluminum has a higher calorific value than hydrocarbon fuel. When a powder fuel scramjet engine operates, the pure cold-state powder fuel experiences processes such as evaporation, oxidation film rupture, surface heterogeneous reaction, gas-phase reaction, and surface condensation after entering the combustion chamber, and requires a long ignition delay time and a high ignition temperature. However, in a supersonic combustion chamber, the airflow velocity is fast, and the residence time of the fuel in the combustion chamber is extremely short, usually at the millisecond level, resulting in a reduction in the combustion efficiency of the powder fuel flow. Summary of the Invention

[0004] Based on this, in view of the above technical problems, it is necessary to provide a powder particle enhanced mixing device for a supersonic combustion chamber, in which the residence time of the powder particles in the partially covered cavity structure is long, and the self-sustained combustion of the combustible gas can increase the temperature in the cavity structure, so that the powder particles have a high combustion efficiency.

[0005] The present invention provides a powder particle enhanced mixing device for a supersonic combustion chamber, including a partially covered cavity structure and at least one gas collection chamber for injecting combustible gas into the interior of the partially covered cavity structure, and the gas collection chamber is communicated with the partially covered cavity structure;

[0006] The partially covered cavity structure is provided with a housing and a first baffle and a second baffle fixedly connected to the interior of the housing for forming a partially covered area inside the partially covered cavity structure;

[0007] The housing includes a first shell section and a second shell section that are communicated with each other and integrally connected. The first shell section is in the shape of a cuboid, the second shell section is in the shape of a frustum of a quadrangular pyramid, the bottom of the second shell section is connected to the first shell section, and the top of the second shell section is set as an opening, serving as the outflow port of the partially covered cavity structure;

[0008] An inlet for supersonic oncoming flow is provided on one side of the first shell section away from the second shell section;

[0009] The first baffle is arranged above the inlet, and the second baffle is arranged below the inlet. Both the first baffle and the second baffle are fixedly connected to the inner side of the first shell section away from the second shell section.

[0010] In one embodiment, the inlet and the outlet are aligned in the horizontal direction.

[0011] The first baffle and / or the second baffle is / are arranged horizontally, or the end of the first baffle and / or the second baffle away from the inlet inclines towards the outside in the vertical direction of partially covering the cavity structure.

[0012] At the top of the first shell section, there is a first two-phase flow injection hole for powdered fuel and fluidizing gas directly above the first baffle, and at the bottom of the second shell section, there is a second two-phase flow injection hole for powdered fuel and fluidizing gas directly below the second baffle.

[0013] In one embodiment, a first gas collecting chamber and a second gas collecting chamber are provided.

[0014] The first gas collecting chamber and the second gas collecting chamber are respectively arranged above and below the inlet, and are both fixedly connected to the side of the first shell section away from the second shell section.

[0015] In one embodiment, along the direction from the inlet to the outlet, a plurality of combustible gas injection holes arranged in parallel penetrate through the first baffle and the second baffle internally.

[0016] Both the first gas collecting chamber and the second gas collecting chamber are provided with a combustible gas inlet and a number of combustible gas outlets equal to the number of combustible gas injection holes, and any one combustible gas injection hole is communicated with one combustible gas outlet.

[0017] In one embodiment, a spiral nozzle is fixedly assembled in the first two-phase flow injection hole for powdered fuel and fluidizing gas and / or the second two-phase flow injection hole for powdered fuel and fluidizing gas. The spiral nozzle extends into the partially covered cavity structure internally, and the spiral nozzle has a plurality of outlets along its spiral flow path.

[0018] In one embodiment, both the first baffle and the second baffle are equal in length and width to the first shell section.

[0019] In one embodiment, the first two-phase flow injection hole for powdered fuel and fluidizing gas is directly above the center position of the first baffle, and the second two-phase flow injection hole for powdered fuel and fluidizing gas is directly below the center position of the second baffle.

[0020] In one embodiment, the distance between the first gas collecting chamber and the second gas collecting chamber is greater than or equal to the height of the inlet.

[0021] In one embodiment, the angle at which one end of the first baffle and / or the second baffle away from the inlet flowside inclines outward in the vertical direction of the partially covered cavity structure is less than or equal to 10°.

[0022] Advantages of the present invention:

[0023] (1) By arranging baffles on the upper and lower sides of the inlet of the partially covered cavity structure, a baffle-covered area is formed inside the cavity structure. The powder fuel and fluidizing gas two-phase flow injection holes are directly above or below the baffle. After the powder fuel enters the baffle-covered area, a small recirculation area will be induced under the action of the baffle. In addition, the powder particles will have a certain velocity under the drive of the fluidizing gas. Due to inertia, the powder particles will collide with the baffle, increasing their movement trajectories in the baffle-covered area. The recirculation area and the collision can increase the residence time of the powder fuel in the partially covered cavity structure, increase the powder fuel concentration, and thus improve the combustion efficiency of the powder fuel. The powder particle enhanced mixing device of the present invention can be used as a supersonic combustor with a high combustion rate.

[0024] (2) By injecting combustible gas into the partially covered cavity structure through the gas collecting chamber, the self-sustained combustion of the combustible gas in the partially covered cavity structure can generate a high-temperature area inside the partially covered cavity structure, creating favorable conditions for the temperature increase of the powder particles, thereby promoting their ignition process and achieving an improvement in combustion efficiency.

[0025] (3) The powder fuel and fluidizing gas two-phase flow injection holes of the present invention are internally equipped with spiral nozzles. The spiral nozzles have multiple outlets along their spiral flow channels. Then, the powder fuel and fluidizing gas two-phase flow can enter the partially covered area from different outlets, being more dispersed, enabling more particles to quickly increase their temperature in the high-temperature area and reach the ignition temperature, creating conditions for efficient combustion. Description of the Drawings

[0026] Figure 1 is a schematic diagram of the overall structure of the powder particle enhanced mixing device for a supersonic combustor provided by an embodiment of the present invention;

[0027] Figure 2 is Figure 1 a schematic diagram of the structure from another angle;

[0028] Figure 3 is Figure 2 a schematic diagram of the cross-sectional structure along the AA plane;

[0029] Figure 4 is Figure 1 a schematic diagram of the structure at one end of the inlet;

[0030] Figure 5 is Figure 4 a schematic diagram of the cross-sectional structure along the BB plane;

[0031] Figure 6 This is the velocity vector diagram of the internal gas flow when the powder particle enhanced mixing device for a supersonic combustion chamber provided by the embodiment of the present invention is working;

[0032] Figure 7 This is the movement trajectory diagram of the internal powder particles when the powder particle enhanced mixing device for a supersonic combustion chamber provided by the embodiment of the present invention is working.

[0033] Explanation of reference numerals: 100, partially covered cavity structure; 110, housing; 111, first housing section; 112, second housing section; 113, outlet; 114, inlet; 120, first baffle; 130, second baffle; 140, first powder fuel and fluidizing gas two-phase flow injection hole; 150, second powder fuel and fluidizing gas two-phase flow injection hole; 200, first gas collecting chamber; 210, combustible gas inlet; 220, combustible gas outlet; 300, second gas collecting chamber; 400, combustible gas injection hole; 500, spiral nozzle. Detailed implementation manners

[0034] To make the above objects, features and advantages of the present invention more obvious and understandable, the following detailed description of the specific implementation manners of the present invention will be given with reference to the accompanying drawings.

[0035] It should be noted that in the description of the present invention, "upper", "lower", "top", "bottom", the orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings. It should be understood that these orientation terms are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation to the present invention. Figure 1 In an embodiment, as shown in, the powder particle enhanced mixing device for a supersonic combustion chamber in this embodiment includes a partially covered cavity structure 100 and at least one gas collecting chamber for injecting combustible gas into the interior of the partially covered cavity structure 100, and the gas collecting chamber is communicated with the partially covered cavity structure 100.

[0036] In this embodiment, the partially covered cavity structure 100 is provided with a housing 110, and a first baffle 120 and a second baffle 130 fixedly connected to the interior of the housing 110 for forming a partially covered area inside the partially covered cavity structure 100. Figures 1 to 3

[0037]

[0038] ​​The housing 110 includes a first housing section 111 and a second housing section 112 that are interconnected and integrally connected. The first housing section 111 is in the shape of a cuboid, and the second housing section 112 is in the shape of a frustum of a square pyramid. The bottom of the second housing section 112 is connected to the first housing section 111, and the top of the second housing section 112 is provided with an opening, serving as an outflow port 113 that partially covers the concave cavity structure 100. The outflow port 113 is used for partially covering and discharging the high-temperature gas generated by fuel combustion and the remaining powder particles in the concave cavity structure 100, and can be connected to the expansion section thereafter.

[0039] It should be noted that the bottom surface of the second housing section 112 with a larger area in the shape of a frustum of a square pyramid is the bottom of the second housing section 112.

[0040] As Figure 4 shown, an inflow port 114 for supersonic oncoming flow is provided on the side of the first housing section 111 away from the second housing section 112 and is aligned in the horizontal direction. Specifically, the inflow port 114 and the outflow port 113 have the same shape and equal size, or the size of the outflow port 113 is larger than that of the inflow port 114.

[0041] The inflow port 114 is used for high-speed air flow to enter and partially cover the concave cavity structure 100, and is connected to the equivalent isolation section.

[0042] A first baffle 120 is provided above the inflow port 114, and a second baffle 130 is provided below the inflow port 114. Both the first baffle 120 and the second baffle 130 are fixedly connected to the inside of the side of the first housing section 111 away from the second housing section 112.

[0043] The first baffle 120 and / or the second baffle 130 are horizontally arranged, or the end of the first baffle 120 and / or the second baffle 130 away from the inflow port 114 is inclined outward in the vertical direction of the partially covered concave cavity structure 100.

[0044] Specifically, the angle at which the end of the first baffle 120 and / or the second baffle 130 away from the inflow port 114 is inclined outward in the vertical direction of the partially covered concave cavity structure 100 is less than or equal to 10°.

[0045] Among them, the position where the bottom surface of the first baffle 120 is connected to the side of the first housing section 111 away from the second housing section 112 is above the top edge of the inflow port 114, or the two are in the same plane. The position where the top surface of the first baffle 120 is connected to the side of the first housing section 111 away from the second housing section 112 is below the bottom edge of the inflow port 114, or the two are in the same plane.

[0046] The baffle can form a covering area with the wall surface of the partially covered concave cavity structure 100 to achieve partial coverage of the concave cavity structure.

[0047] In this embodiment, a first two-phase flow injection hole 140 of powder fuel and fluidizing gas is provided directly above the top of the first shell segment 111 and located directly above the first baffle 120, and a second two-phase flow injection hole 150 of powder fuel and fluidizing gas is provided directly below the bottom of the second shell segment 112 and located directly below the second baffle 130. The function of the fluidizing gas is to transport the powder fuel.

[0048] When the two-phase flow of powder fuel and fluidizing gas enters the covering area, due to the presence of the baffle, after the powder fuel enters the baffle covering area, a small recirculation area will be induced under the action of the baffle, and the velocity of the powder fuel in the baffle covering area is smaller than that of the powder fuel in the concave cavity structure, increasing the residence time of the powder particles in the concave cavity. In addition, under the action of the fluidizing gas, the powder fuel has a certain initial velocity, and under the action of inertia, it will collide with the baffle along its movement trajectory, extending its movement trajectory in the covering area, thereby increasing the residence time.

[0049] In one of the embodiments, a first gas collecting chamber 200 and a second gas collecting chamber 300 are provided; the first gas collecting chamber 200 and the second gas collecting chamber 300 are respectively arranged above and below the inlet 114, and are both fixedly connected to the side of the first shell segment 111 away from the second shell segment 112. The distance between the first gas collecting chamber 200 and the second gas collecting chamber 300 is greater than or equal to the height of the inlet 114.

[0050] In one of the embodiments, as Figure 5 shown, along the direction from the inlet 114 to the outlet 113, a plurality of parallel arranged combustible gas injection holes 400 penetrate through the first baffle 120 and the second baffle 130; the first gas collecting chamber 200 and the second gas collecting chamber 300 are both provided with a combustible gas inlet 210 and a combustible gas outlet 220 with the same number as the combustible gas injection holes 400, and any one of the combustible gas injection holes 400 is communicated with a combustible gas outlet 220.

[0051] Specifically, the combustible gas inlets 210 of the first gas collecting chamber 200 and the second gas collecting chamber 300 are both communicated with an external combustible gas supply device.

[0052] The first gas collecting chamber 200 is used to introduce combustible gas into a part of the covered concave cavity structure 100 through the combustible gas injection holes 400 in the first baffle 120, and the second gas collecting chamber 300 is used to introduce combustible gas into a part of the covered concave cavity structure 100 through the combustible gas injection holes 400 in the second baffle 130. After the combustible gas enters the part of the covered concave cavity structure 100, it can self-ignite and generate a high-temperature area inside the part of the covered concave cavity structure 100, creating favorable conditions for heating the powder particles, thereby promoting the ignition process of the powder particles and improving the combustion efficiency.

[0053] In one embodiment, a spiral nozzle 500 is fixedly assembled in the first pulverized fuel and fluidizing gas two-phase flow injection hole 140 and / or the second pulverized fuel and fluidizing gas two-phase flow injection hole 150. The spiral nozzle 500 extends into the interior of the partially covered cavity structure 100, and the spiral nozzle 500 has a plurality of outlets along its spiral flow path.

[0054] Driven by the fluidizing gas, the powder particles can enter the baffle-covered area from different outlets, and the entry situation is more dispersed, which can increase the heating rate of the powder particles.

[0055] Specifically, one end of the spiral flow path of the spiral nozzle 500 is connected to the pneumatic drive piston supply device, and the other end is an outlet, and the direction of this outlet is preferably aligned with the inlet 114 of the partially covered cavity structure 100.

[0056] In one embodiment, both the first baffle 120 and the second baffle 130 are equal in length and width to the first shell section 111, achieving full coverage in the vertical direction.

[0057] In one embodiment, the first pulverized fuel and fluidizing gas two-phase flow injection hole 140 is directly above the center position of the first baffle 120, and the second pulverized fuel and fluidizing gas two-phase flow injection hole 150 is directly below the center position of the second baffle 130. Then, when the two-phase flow of pulverized fuel and fluidizing gas enters the covered area from the spiral nozzle 500, it is more uniform.

[0058] To verify the beneficial effects of the present invention, a fluent numerical simulation method is adopted. A set of specific structural parameters and working parameters of the powder particle enhanced mixing device for a supersonic combustor are set, and a velocity vector diagram of the internal air flow of the powder particle enhanced mixing device for a supersonic combustor of the present invention during operation is obtained as Figure 6 shown, and a movement trajectory diagram of the powder particles is as Figure 7 shown.

[0059] It should be noted that under the condition of satisfying the above-described embodiments, the structural parameters and working parameters of the powder particle enhanced mixing device for a supersonic combustor can be specifically set by those skilled in the art according to the actual size of the powder particles.

[0060] From Figure 6 it can be seen that within the baffle-covered area, the direction and magnitude of the air flow velocity in the covered area formed after adding the baffle have changed greatly compared with the uncovered area, the velocity decreases and a small recirculation area is formed. The powder particles move with the air flow. The powder particles slow down in the covered area and perform a recirculation movement, increasing the residence time within the entire partially covered cavity structure 100. From Figure 7It can be seen that the particle trajectory density is relatively large within the baffle coverage area. It can be seen that due to the presence of the baffle, most of the powder particles will move within the baffle coverage area, increasing the residence time of the powder particles within the partially covered cavity structure 100. The increase in the residence time of the powder particles within the partially covered cavity structure 100 can play a good buffering role in the blending and temperature increase of the powder particles.

[0061] The above-described embodiments merely represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the present invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the appended claims.

Claims

1. A powder particle enhanced mixing device for a supersonic combustion chamber, characterized in that It includes a partially covered cavity structure (100) and at least one gas collecting chamber for injecting combustible gas into the interior of the partially covered cavity structure (100), and the gas collecting chamber is communicated with the partially covered cavity structure (100); The partially covered cavity structure (100) is provided with a housing (110), a first baffle (120) and a second baffle (130) fixedly connected inside the housing (110) for forming a partially covered area inside the partially covered cavity structure (100); The housing (110) includes a first housing section (111) and a second housing section (112) which are communicated with each other and integrally connected. The first housing section (111) is in the shape of a cuboid, the second housing section (112) is in the shape of a frustum of a quadrangular pyramid, the bottom of the second housing section (112) is connected to the first housing section (111), and the top of the second housing section (112) is set as an opening, serving as an outflow port (113) of the partially covered cavity structure (100); An inlet port (114) for supersonic oncoming flow is arranged on one side of the first housing section (111) away from the second housing section (112). The first baffle (120) is arranged above the inlet port (114), the second baffle (130) is arranged below the inlet port (114), and both the first baffle (120) and the second baffle (130) are fixedly connected to the inside of one side of the first housing section (111) away from the second housing section (112).

2. The powder particle enhanced mixing device for a supersonic combustion chamber according to claim 1, wherein The inlet port (114) and the outflow port (113) are aligned in the horizontal direction; The first baffle (120) and / or the second baffle (130) are horizontally arranged, or one end of the first baffle (120) and / or the second baffle (130) away from the inlet port (114) inclines outward in the vertical direction of the partially covered cavity structure (100); A first two-phase flow injection hole (140) for first powder fuel and fluidizing gas is arranged directly above the first baffle (120) at the top of the first housing section (111), and a second two-phase flow injection hole (150) for second powder fuel and fluidizing gas is arranged directly below the second baffle (130) at the bottom of the second housing section (112).

3. The powder particle enhanced mixing device for a supersonic combustion chamber according to claim 1, characterized in that, A first gas collecting chamber (200) and a second gas collecting chamber (300) are provided; The first gas collecting chamber (200) and the second gas collecting chamber (300) are respectively arranged above and below the inlet port (114), and are both fixedly connected to one side of the first housing section (111) away from the second housing section (112).

4. The powder particle reinforced mixing device for a supersonic combustion chamber according to claim 3, characterized in that, Along the direction from the inlet port (114) to the outflow port (113), a plurality of combustible gas injection holes (400) arranged in parallel are penetrated through the interiors of the first baffle (120) and the second baffle (130); Both the first gas collecting chamber (200) and the second gas collecting chamber (300) are provided with a combustible gas inlet (210) and combustible gas outlets (220) with the same number as the combustible gas injection holes (400), and any one combustible gas injection hole (400) is communicated with one combustible gas outlet (220).

5. The powder particle enhanced mixing device for a supersonic combustor according to claim 1, wherein, A spiral nozzle (500) is fixedly assembled in the first powder fuel and fluidizing gas two-phase flow injection hole (140) and / or the second powder fuel and fluidizing gas two-phase flow injection hole (150). The spiral nozzle (500) extends into the interior of the partially covered cavity structure (100), and the spiral nozzle (500) has a plurality of outlets along its spiral flow path.

6. The powder particle reinforced mixing device for a supersonic combustion chamber according to claim 4 or 5, characterized in that, Both the first baffle (120) and the second baffle (130) are equal in length and width to the first shell section (111).

7. The powder particle enhanced mixing device for a supersonic combustion chamber according to claim 6, wherein, The first powder fuel and fluidizing gas two-phase flow injection hole (140) is directly above the center position of the first baffle (120), and the second powder fuel and fluidizing gas two-phase flow injection hole (150) is directly below the center position of the second baffle (130).

8. The powder particle enhanced mixing device for a supersonic combustor according to claim 7, wherein, The distance between the first gas collecting chamber (200) and the second gas collecting chamber (300) is greater than or equal to the height of the inlet port (114).

9. The powder particle enhanced mixing device for a supersonic combustion chamber according to claim 1, characterized in that, The angle at which the end of the first baffle (120) and / or the second baffle (130) away from the inlet port (114) inclines outward in the vertical direction of the partially covered cavity structure (100) is less than or equal to 10°.

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