Catalytic bed and propelling system for gel hydrogen peroxide

Abstract

The invention provides a catalytic bed for gel hydrogen peroxide and a propelling system, and relates to the technical field of aerospace propelling system engines. The invention provides a catalytic bed for gel hydrogen peroxide, which comprises a catalytic bed shell, an injection cavity and a catalytic cavity, the capillary injection pipe is arranged in the injection cavity and is used for receiving the gel hydrogen peroxide and converting the gel hydrogen peroxide into liquid hydrogen peroxide; the atomization injector is arranged in the injection cavity and connected with the catalytic bed shell, and the atomization injector is communicated with the capillary injection pipe and the catalytic cavity; wherein the atomization injector is arranged to be capable of atomizing liquid hydrogen peroxide conveyed by the capillary injection pipe and conveying the atomized hydrogen peroxide into the catalytic chamber for catalytic decomposition. Through the structural design of the catalytic bed, the gel hydrogen peroxide can be effectively diffused in the catalytic bed and is in contact with the catalyst, and the catalytic decomposition efficiency of the gel hydrogen peroxide is remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of aerospace propulsion system engines, and more particularly to a catalytic bed and a propulsion system for gelled hydrogen peroxide. Background Art

[0002] Traditional solid or liquid rocket engines use solids or liquids as propellants, and it is difficult to balance the requirements of attitude control accuracy, structural simplification, safety, long-term storage, and high energy density. Gelled propellants can combine the advantages of solid and liquid propellants to achieve complementary performance advantages of solid and liquid propellants.

[0003] Gelled propellants exhibit a highly viscous gel state under static conditions, can maintain their shape, and significantly reduce the risk of storage leakage; they quickly liquefy when subjected to mechanical shear or temperature stimulation, facilitating transportation and combustion regulation, and at the same time having the safety characteristics of insensitive munitions. Hydrogen peroxide, as a green oxidant, has only oxygen and water vapor as its catalytic decomposition products and is an ideal substrate for gelled propellants. By adding a gelling agent to hydrogen peroxide, a gelled propellant with both high safety and environmental protection characteristics can be made. However, gelled hydrogen peroxide has an extremely high viscosity and is difficult to effectively diffuse and contact the catalyst in a conventional catalytic bed, resulting in extremely low decomposition efficiency or even inability to trigger the reaction, seriously restricting its practical application process in aerospace propulsion systems.

[0004] In view of this, the present application is specifically proposed. Summary of the Invention

[0005] The present application provides a catalytic bed and a propulsion system for gelled hydrogen peroxide, aiming to solve the problem in the prior art that gelled hydrogen peroxide has an extremely high viscosity and is difficult to effectively diffuse and contact the catalyst in a conventional catalytic bed, resulting in extremely low decomposition efficiency or even inability to trigger the reaction, seriously restricting its practical application process in aerospace propulsion systems.

[0006] On the one hand, the present application provides a catalytic bed for gelled hydrogen peroxide, including: a catalytic bed housing, forming a jet chamber and a catalytic chamber; a capillary jet pipe, arranged in the jet chamber, for receiving gelled hydrogen peroxide and converting the gelled hydrogen peroxide into liquid hydrogen peroxide; an atomizing injector, arranged in the jet chamber and connected to the catalytic bed housing, and the atomizing injector is communicated with the capillary jet pipe and the catalytic chamber; wherein, the atomizing injector is configured to be able to atomize the liquid hydrogen peroxide conveyed by the capillary jet pipe and convey the atomized hydrogen peroxide into the catalytic chamber for catalytic decomposition.

[0007] In some embodiments, a first injection hole and a second injection hole are formed in the atomizing injector, and the first injection hole and the second injection hole are respectively communicated with corresponding capillary injection tubes; wherein, the axis of the first injection hole intersects with the axis of the second injection hole, so that the liquid hydrogen peroxide flowing out through the first injection hole and the second injection hole collides to atomize the liquid hydrogen peroxide.

[0008] In some embodiments, the included angle between the axis of the first injection hole and the axis of the second injection hole is 20 to 100°; and / or both the first injection hole and the second injection hole are multiple in number. The multiple first injection holes are arranged in a spaced-apart and circumferential manner in the first area of the atomizing injector, and the multiple second injection holes are arranged in a spaced-apart and circumferential manner in the second area of the atomizing injector. The first area is located inside the second area in the radial direction of the atomizing injector, and the first injection holes and the second injection holes are arranged in one-to-one correspondence.

[0009] In some embodiments, a high-pressure air inlet is formed in the catalytic bed housing, and the high-pressure air inlet is communicated with the injection chamber to supply high-pressure gas to the injection chamber; a third injection hole and a fourth injection hole are formed in the atomizing injector. The third injection hole is communicated with the capillary injection tube, and the fourth injection hole is communicated with the injection chamber; wherein, the axis of the fourth injection hole intersects with the axis of the third injection hole, so that the high-pressure gas ejected through the fourth injection hole can collide with the liquid hydrogen peroxide ejected through the third injection hole to atomize the liquid hydrogen peroxide.

[0010] In some embodiments, there are multiple high-pressure air inlets, and the multiple high-pressure air inlets are arranged in a circumferential manner on the inner wall of the injection chamber; the included angle between the axis of the fourth injection hole and the axis of the third injection hole is 20 to 100°; and / or the fourth injection holes are symmetrically arranged, and the third injection hole is arranged between two paired fourth injection holes.

[0011] In some embodiments, the catalytic bed further includes a partition and flow equalizing plate, which is arranged in the catalytic chamber and connected to the catalytic bed housing to divide the catalytic chamber into a front-bed catalytic chamber and a rear-bed catalytic chamber; a number of flow equalizing through holes are formed in the partition and flow equalizing plate to communicate the front-bed catalytic chamber and the rear-bed catalytic chamber; the front-bed catalytic chamber is located between the injection chamber and the rear-bed catalytic chamber, and a chemical reaction type catalyst is arranged in the front-bed catalytic chamber, and a mesh-based catalyst is arranged in the rear-bed catalytic chamber to catalytically decompose the atomized hydrogen peroxide injected by the atomizing injector in stages.

[0012] The chemical reaction type catalyst provided in the front bed catalytic chamber can undergo violent oxidation-reduction reactions and catalytic decomposition reactions with hydrogen peroxide such as hydrogen peroxide to achieve the rapid startup and rapid temperature rise of the catalytic bed, and prompt the rapid increase in the decomposition efficiency; after the partially decomposed hydrogen peroxide and its decomposition gas in the front bed catalytic chamber enter the rear bed catalytic chamber and come into contact with the surface of the mesh-based catalyst provided in the rear bed catalytic chamber, a stable catalytic decomposition reaction occurs, further improving the catalytic decomposition efficiency, achieving the complete decomposition of hydrogen peroxide, and increasing the bed loading capacity of the catalytic bed. Thus, the purpose of comprehensively using the chemical reaction type catalyst and the mesh-based catalyst is to utilize the advantageous intervals of the two catalysts. The chemical reaction type catalyst realizes the rapid startup and rapid temperature rise of the catalytic bed, and the mesh-based catalyst can improve the decomposition efficiency and bed loading capacity of the catalytic bed.

[0013] In some embodiments, it further includes a filter screen, and the filter screen is arranged on the front and rear bed partition and flow equalizing plate to prevent the chemical reaction type catalyst from entering the rear bed catalytic chamber.

[0014] In some embodiments, the catalytic bed further includes a direct current injection panel and an outlet flow equalizing plate; feeding ports and discharging ports are respectively formed at both ends of the catalytic bed housing; the direct current injection panel is arranged in the injection chamber and is connected to the catalytic bed housing. A number of feeding through holes communicating with the feeding ports are formed on the direct current injection panel, and the capillary injection tubes are communicated with the feeding through holes; the outlet flow equalizing plate is arranged in the rear bed catalytic chamber and is connected to the catalytic bed housing. A number of discharging through holes communicating with the discharging ports are formed on the outlet flow equalizing plate.

[0015] In some embodiments, the chemical reaction type catalyst includes a carrier and an active component supported on the carrier, and the active component includes at least one of sodium borohydride, potassium permanganate, sodium permanganate or manganese oxide; and / or the mesh-based catalyst is a metal wire mesh plated with a catalytic active component, and the catalytic active component includes at least one of silver, platinum, palladium, iridium, ruthenium.

[0016] In some embodiments, the catalytic bed housing further forms a heat exchange chamber, and the heat exchange chamber surrounds the injection chamber and the catalytic chamber in the circumferential direction for circulating a heat exchange medium to preheat the catalyst in the catalytic bed.

[0017] In some embodiments, a heat exchange medium inlet and a heat exchange medium outlet respectively communicating with the heat exchange chamber are formed on the catalytic bed housing for the heat exchange medium to flow into or out of the heat exchange chamber; and / or a plurality of fins are arranged in the heat exchange chamber, and the plurality of fins are arranged at intervals in the circumferential direction of the catalytic chamber to divide the heat exchange chamber into a plurality of heat exchange channels.

[0018] On the other hand, the present application provides a propulsion system, which includes a catalytic bed as described above, and also includes a conveying device and a combustion chamber; the conveying device is communicated with the injection chamber to convey gelled hydrogen peroxide to the catalytic bed; the combustion chamber is communicated with the catalytic chamber to receive the high-temperature gas generated after the catalytic decomposition of gelled hydrogen peroxide; the nozzle is communicated with the combustion chamber to convert the thermal energy generated by the high-temperature gas in the combustion chamber into kinetic energy.

[0019] Compared with the prior art, the catalytic bed and the propulsion system for gelled hydrogen peroxide provided by the present application have at least the following beneficial effects:

[0020] Through the structural design of the catalytic bed, the injection chamber and the catalytic chamber are designed in the catalytic bed. The capillary injection tubes and the atomizing injectors are both arranged in the injection chamber, and the catalytic chamber is used to arrange the catalysts for promoting the decomposition reaction of hydrogen peroxide; after the gelled catalyst is fed into the catalytic bed, it enters the capillary injection tubes. The capillary injection tubes can provide a large shear force through a high pressure drop, so as to promote the opening of the hydrogen bonds between the gel factors in the gelled hydrogen peroxide, making the gelled hydrogen peroxide shear-thinning and the viscosity decreasing, which is beneficial to promoting the transformation of gelled hydrogen peroxide into a liquid state; the hydrogen peroxide processed by the capillary injection tubes passes through the atomizing injectors, and the atomizing injectors can inject and atomize it, that is, make the hydrogen peroxide liquid flow quickly form a liquid film, the liquid film breaks into liquid filaments, and the liquid filaments continue to break to generate small droplets, and perform catalytic decomposition with the catalysts in the catalytic chamber.

[0021] Thus, the gelled hydrogen peroxide is transformed from a gel state to tiny droplets under the synergistic action of the capillary injection tubes and the atomizing injectors, which is beneficial to quickly diffuse in the catalytic chamber and fully contact with the catalysts, thereby significantly improving the catalytic decomposition efficiency and effectively promoting the practical application process of gelled hydrogen peroxide in the aerospace propulsion system.

[0022] Other advantages and features of the catalytic bed and the propulsion system for gelled hydrogen peroxide provided by the present application will be elaborated in detail in the subsequent specific embodiments. Description of the Drawings

[0023] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required to be used in the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative efforts.

[0024] Figure 1 It is a perspective cross-sectional view of the catalytic bed provided according to an embodiment of the present application;

[0025] Figure 2 It is another perspective cross-sectional view of the catalytic bed provided according to an embodiment of the present application;

[0026] Figure 3 It is a schematic structural diagram of an atomizing injector provided according to an embodiment of the present application;

[0027] Figure 4 It is a cross-sectional view of an atomizing injector provided according to an embodiment of the present application;

[0028] Figure 5 It is a schematic structural diagram of an atomizing injector provided according to another embodiment of the present application;

[0029] Figure 6 It is a cross-sectional view of an atomizing injector provided according to another embodiment of the present application;

[0030] Figure 7 It is a schematic structural diagram of a partitioned flow equalizing plate provided according to an embodiment of the present application;

[0031] Figure 8 It is a partial structural schematic view of a catalytic bed housing from one perspective provided according to an embodiment of the present application;

[0032] Figure 9 It is a partial structural schematic view of a catalytic bed housing from another perspective provided according to an embodiment of the present application;

[0033] Figure 10 It is a partial structural cross-sectional view of a catalytic bed housing provided according to an embodiment of the present application;

[0034] Figure 11 It is a module schematic diagram of a propulsion system provided according to an embodiment of the present application.

[0035] The reference numerals are as follows:

[0036] 100, catalytic bed;

[0037] 10, catalytic bed housing; 11, feed inlet; 12, discharge outlet; 13, heat exchange medium inlet; 14, heat exchange medium outlet; 15, fin; A, injection chamber; B, catalytic chamber; B1, front bed catalytic chamber; B2, rear bed catalytic chamber; C, heat exchange chamber; 10A, high-pressure air inlet;

[0038] 20, capillary injection tube;

[0039] 30, atomizing injector; 30A, first injection hole; 30B, second injection hole; 30C, third injection hole; 30D, fourth injection hole;

[0040] 40, partitioned flow equalizing plate;

[0041] 50, direct current injection panel;

[0042] 60, outlet flow equalizing plate;

[0043] 70. Support ring

[0044] 1000. Propulsion system; 200. Conveyor; 300. Combustion chamber; 400. Nozzle Detailed implementation manners

[0045] In the description of the present invention, it should be understood that, when descriptions indicating orientation or positional relationships such as the terms "center", "inner", "outer", "axial direction", "radial direction", "circumferential direction", etc. appear, without special instructions, they are understood as being based on the orientation or positional relationships shown in the drawings. This is 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 therefore should not be construed as a limitation to the present invention

[0046] In addition, when features limited by "first" and "second" are only for descriptive purposes, they should not be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Features limited by "first" and "second" may explicitly or implicitly include at least one of the limited features. When descriptions such as "a plurality of" appear, the general meaning is at least including two, such as two, three, etc., unless otherwise specifically limited

[0047] It should be noted that the main characteristics of the gel hydrogen peroxide in the embodiments of the present application are high viscosity, certain plasticity, can maintain a certain shape when stationary, and become liquid after being stimulated by the outside world (mechanical stirring, temperature change), belonging to non-Newtonian fluid; the gel factor used in the gel hydrogen peroxide is a shear-thinning gel, with certain viscoelasticity, and its liquefaction can be achieved by applying a certain shear rate to it; when subjected to the action of an external shear force, the hydrogen bonds originally formed between the gel factors will be broken, and the three-dimensional gel network will also be broken accordingly. At this time, the gel system is broken under the action of the shear force. When the gel propellant in the embodiments of the present application is gel hydrogen peroxide, the viscosity range of the gel hydrogen peroxide is 1 - 500 Pa·s

[0048] As described above, since the high viscosity and low fluidity of the gel hydrogen peroxide are the key factors restricting its catalytic decomposition in a conventional catalytic bed, the general inventive concept of the present application is to provide a catalytic bed 100 and a propulsion system 1000 for the gel hydrogen peroxide. Through the structural design of the catalytic bed 100 and the propulsion system 1000, the gel hydrogen peroxide can reduce its viscosity under the action of the capillary injection tube 20 and the atomizing injector 30, change from the gel state to the liquid state, and after atomization, contact with the catalyst, so as to significantly increase the contact area with the catalyst, improve its fluidity, and further effectively improve the catalytic decomposition efficiency

[0049] Based on the above concept, with reference to Figure 1 and Figure 2As shown Figure 1 is a perspective cross-sectional view of a catalytic bed 100 provided according to an embodiment of the present application; Figure 2 is another perspective cross-section of the catalytic bed 100 provided according to an embodiment of the present application.

[0050] An embodiment of the present application provides a catalytic bed 100 for gel hydrogen peroxide, including: a catalytic bed housing 10, formed with a jet chamber A and a catalytic chamber B; a capillary jet tube 20, arranged in the jet chamber A, for receiving gel hydrogen peroxide and converting the gel hydrogen peroxide into liquid hydrogen peroxide; an atomizing injector 30, arranged in the jet chamber A and connected to the catalytic bed housing 10, and the atomizing injector 30 is communicated with the capillary jet tube 20 and the catalytic chamber B; wherein, the atomizing injector 30 is configured to atomize the liquid hydrogen peroxide conveyed by the capillary jet tube 20 and convey the atomized hydrogen peroxide into the catalytic chamber B for catalytic decomposition.

[0051] In an embodiment of the present application, the main function of the catalytic bed housing 10 is to provide a support structure. The catalytic bed housing 10 can be generally cylindrical as a whole. The jet chamber A and the catalytic chamber B can be axially distributed. The catalytic bed housing 10 adopting a divided chamber design (jet chamber A and catalytic chamber B) can realize the step-by-step treatment of hydrogen peroxide liquefaction and catalytic decomposition, and avoid the low reaction efficiency caused by the direct contact between unatomized gel hydrogen peroxide and the catalyst.

[0052] The capillary jet tube 20 and the atomizing injector 30 are arranged in the jet chamber A. The capillary jet tube 20 is arranged at the feed end of the gel hydrogen peroxide of the catalytic bed 100. The atomizing injector 30 is arranged between the capillary jet tube 20 and the catalytic chamber B and is respectively communicated with the capillary jet tube 20 and the catalytic chamber B. When the catalytic bed 100 works, the gel hydrogen peroxide enters the capillary jet tube 20. The capillary jet tube 20 provides a relatively high pressure drop to apply a high shear force to the gel hydrogen peroxide, destroys the three-dimensional network structure of the gel factor, realizes shear thinning, converts the high-viscosity gel into a liquid state. Subsequently, the atomizing injector 30 receives the liquid hydrogen peroxide conveyed by the capillary jet tube 20. During the flow of the liquid hydrogen peroxide, a liquid film is formed from the liquid flow, the liquid film breaks into liquid filaments, and the liquid filaments continue to break to generate liquid droplets, thereby realizing atomizing injection, so as to significantly improve the fluidity of hydrogen peroxide, increase the contact area with the catalyst, and effectively improve the catalytic decomposition efficiency of hydrogen peroxide.

[0053] It should be understood that the atomizing injector 30 in the embodiment of the present application has relatively high jet atomization performance compared with the direct current injector in the traditional catalytic bed, and can improve the jet atomization of gel hydrogen peroxide. For example, the atomizing injector 30 can be an impact injector or an air-assisted injector, etc.

[0054] Continue to refer to Figure 1 、 Figure 3 andFigure 4 As shown Figure 3 FIG. 30 is a schematic structural view of an atomizing injector 30 provided according to an embodiment of the present application; Figure 4 FIG. 31 is a cross-sectional view of the atomizing injector 30 provided according to an embodiment of the present application.

[0055] In some embodiments, the atomizing injector 30 is an impact injector. The atomizing injector 30 is provided with a first injection hole 30A and a second injection hole 30B. The first injection hole 30A and the second injection hole 30B are respectively communicated with corresponding capillary injection tubes 20; wherein, the axis of the first injection hole 30A intersects with the axis of the second injection hole 30B, so that the liquid hydrogen peroxide flowing out through the first injection hole 30A and the second injection hole 30B collides to atomize the liquid hydrogen peroxide.

[0056] In the embodiment of the present application, the atomizing injector 30 is an impact injector. The atomizing injector 30 is plate-shaped and arranged at one end of the injection chamber A close to the catalytic chamber B. The atomizing injector 30 is provided with a first injection hole 30A and a second injection hole 30B. The first injection hole 30A and the second injection hole 30B are respectively connected to the corresponding capillary injection tubes 20 and communicated, and the axis of the first injection hole 30A intersects with the axis of the second injection hole 30B. Thus, the liquid hydrogen peroxide ejected from the first injection hole 30A and the second injection hole 30B can collide to form a liquid film, the liquid film breaks into liquid filaments, and the liquid filaments continue to break to generate liquid droplets, thereby realizing the atomization of the liquid hydrogen peroxide.

[0057] It can be understood that the diameter of the hydrogen peroxide droplets formed in this embodiment depends on the diameters of the nozzles of the first injection hole 30A and the second injection hole 30B, the injection pressure drop, the pressure of the catalytic bed, the impact angle, etc. The liquid hydrogen peroxide jets ejected from the first injection hole 30A and the second injection hole 30B collide to generate a planar liquid film. The liquid film continuously generates circular surface waves and continuously diffuses. The disturbance of the surface air causes the liquid film to break and generate liquid droplets. The tiny liquid droplets generated by the breakage increase the wettability with the solid, thereby increasing the contact area between the gel catalyst and the catalyst in the catalytic bed.

[0058] The impact injector in the embodiment of the present application has a better atomization effect on the gel hydrogen peroxide than the traditional direct current type and centrifugal type injectors; as the jet Reynolds number and Weber number increase, the atomization modes of the gel liquid film of the impact injector are successively the edge closed mode, the edge open mode, the non-edge ray mode, the liquid filament separation mode, and the fully developed mode.

[0059] In the embodiments of the present application, the nozzle ends of the first injection hole 30A and the second injection hole 30B can adopt a conical structure, reduce the aspect ratio of the nozzle outlet, and have a square or elliptical nozzle outlet to facilitate the rupture of the gel liquid film. Moreover, the atomization effect of the liquid film can be improved by increasing the number of injection ports, injection pressure, impingement angle, temperature, chamber pressure, and reducing the injection port flow rate, impingement distance, etc.

[0060] Further, referring to Figure 4 , when the atomizing injector 30 is an impact-type injector, the included angle between the axis of the first injection hole 30A and the axis of the second injection hole 30B is 20 to 100°, and this included angle between the axes is the impingement angle of the two streams of liquid hydrogen peroxide.

[0061] Further, referring to Figure 3 and Figure 4 , both the first injection hole 30A and the second injection hole 30B are provided in multiple numbers. The multiple first injection holes 30A are arranged at intervals in a ring in the first area of the atomizing injector 30, and the multiple second injection holes 30B are arranged at intervals in a ring in the second area of the atomizing injector 30. The first area is located inside the second area in the radial direction of the atomizing injector 30, and the first injection hole 30A and the second injection hole 30B are arranged in one-to-one correspondence; thus, the first injection hole 30A and the second injection hole 30B can be arranged in a double-ring annular pattern. The first injection holes 30A in the inner ring are inclined at a certain angle towards the second injection holes 30B, and the second injection holes 30B in the outer ring are inclined at a certain angle towards the first injection holes 30A, so that when the liquid hydrogen peroxide passes through the atomizing injector 30, the liquid hydrogen peroxide jets ejected from the first injection holes 30A and the second injection holes 30B in the inner and outer rings will collide with each other, thereby realizing atomization.

[0062] Continuing to refer to Figure 1 , Figure 5 and Figure 6 shown, Figure 5 is a schematic structural diagram of the atomizing injector 30 according to another embodiment of the present application; Figure 6 is a cross-sectional view of the atomizing injector 30 according to another embodiment of the present application;

[0063] In some other embodiments, when the atomizing injector 30 is a gas-assisted injector, the catalytic bed housing 10 is provided with a high-pressure air inlet 10A, and the high-pressure air inlet 10A is communicated with the injection chamber A for supplying high-pressure gas into the injection chamber A; the atomizing injector 30 is provided with a third injection hole 30C and a fourth injection hole 30D. The third injection hole 30C is communicated with the capillary injection tube 20, and the fourth injection hole 30D is communicated with the injection chamber A; wherein, the axis of the fourth injection hole 30D intersects with the axis of the third injection hole 30C, so that the high-pressure gas ejected through the fourth injection hole 30D can collide with the liquid hydrogen peroxide ejected through the third injection hole 30C to atomize the liquid hydrogen peroxide.

[0064] The gas-assisted injector is a gas-coordinated atomizing injector. The main principle is to use compressed air to atomize the gel hydrogen peroxide. Exemplarily, the gas-assisted injector uses the interaction between a high-speed air flow and liquid hydrogen peroxide to generate a shear force, causing the hydrogen peroxide liquid flow to break and become unstable and then achieve atomization.

[0065] When the atomizing injector 30 in this embodiment is a gas-assisted injector, the atomizing injector 30 is in a plate shape and is arranged at one end of the injection chamber A close to the catalytic chamber B to separate the injection chamber A from the catalytic chamber B. The atomizing injector 30 is provided with a third injection hole 30C and a fourth injection hole 30D. The third injection hole 30C is communicated with the capillary injection tube 20, and the fourth injection hole 30D is communicated with the injection chamber A; to realize the supply of high-pressure air, the catalytic bed housing 10 is provided with a high-pressure air inlet 10A, and the high-pressure air inlet 10A is opened on the inner wall of the injection chamber A and is communicated with the injection chamber A, so that high-pressure gas can be injected into the injection chamber A and then introduced into the fourth injection hole 30D; since the axis of the fourth injection hole 30D intersects with the axis of the third injection hole 30C, the liquid hydrogen peroxide supplied by the capillary injection tube 20 into the third injection hole 30C is ejected through the third injection hole 30C and forms a liquid film under the impact of the high-pressure gas in the fourth injection hole 30D. The liquid film breaks into liquid filaments, and the liquid filaments continue to break to generate liquid droplets, thereby increasing the contact area with the subsequent catalyst.

[0066] It should be understood that during the atomization process, different magnitudes of gas-liquid shear effects will generate different forms of surface waves on the surface of the liquid jet. The continuous amplification of the surface wave amplitude will ultimately lead to the instability of the liquid jet. As the gas-liquid momentum ratio continues to increase, the enhancement of the aerodynamic force will promote the fragmentation process of the liquid jet. After the initial atomization process ends, a large number of liquid filament structures will be formed in the spray field. Therefore, the atomization effect of the atomizing injector 30 when it is a gas-assisted injector can be improved by increasing the gas-liquid momentum ratio, increasing the gas-liquid impact angle, increasing the quantity, injection pressure, temperature, chamber pressure, etc.

[0067] Further, referring to Figure 10 shown, it is a partial structural cross-sectional view of the catalytic bed housing 10 provided by the embodiment of the present application. In the embodiment of the present application, a plurality of high-pressure air inlets 10A are provided, and the plurality of high-pressure air inlets 10A are arranged in a ring on the inner wall of the injection chamber A to increase the injection amount of high-pressure gas.

[0068] Further, referring to Figure 5 and Figure 6 , in the embodiment of the present application, the included angle between the axis of the fourth injection hole 30D and the axis of the third injection hole 30C can be 20 to 100°, and this included angle is the impact angle between the liquid hydrogen peroxide and the high-pressure gas.

[0069] Further, the fourth injection holes 30D are symmetrically arranged, and the third injection holes 30C are arranged between two paired fourth injection holes 30D. Thus, the liquid hydrogen peroxide ejected from each third injection hole 30C can be atomized under the action of the high-pressure gas provided by the two fourth injection holes 30D, so as to further improve the atomization effect.

[0070] In some embodiments, referring Figure 1 , Figure 2 and Figure 7 shown, Figure 7 FIG. is a schematic structural view of the partition and flow equalizing plate 40 provided by an embodiment of the present application; the catalytic bed 100 further includes a partition and flow equalizing plate 40, and the partition and flow equalizing plate 40 is arranged in the catalytic chamber B and connected to the catalytic bed housing 10 to divide the catalytic chamber B into a front bed catalytic chamber B1 and a rear bed catalytic chamber B2; a plurality of flow equalizing holes are formed in the partition and flow equalizing plate 40, and the flow equalizing holes communicate the front bed catalytic chamber B1 and the rear bed catalytic chamber B2; the front bed catalytic chamber B1 is located between the injection chamber A and the rear bed catalytic chamber B2, and a chemical reaction type catalyst is arranged in the front bed catalytic chamber B1, and a mesh-based catalyst is arranged in the rear bed catalytic chamber B2 to catalytically decompose the atomized hydrogen peroxide injected by the atomizing injector 30 in stages.

[0071] The partition and flow equalizing plate 40 in this embodiment is in a plate shape, and the partition and flow equalizing plate 40 is arranged in the catalytic chamber B and connected to the catalytic bed housing 10 to divide the catalytic chamber B into a front bed catalytic chamber B1 and a rear bed catalytic chamber B2. The front bed catalytic chamber B1 receives the hydrogen peroxide injected by the atomizing injector 30 to catalytically decompose it. A plurality of flow equalizing holes are formed in the partition and flow equalizing plate 40, and the flow equalizing holes communicate the front bed catalytic chamber B1 and the rear bed catalytic chamber B2, so that the rear bed catalytic chamber B2 can continue to catalytically decompose the unreacted hydrogen peroxide after the catalytic treatment in the front bed catalytic chamber B1, so that the gelled hydrogen peroxide can be completely decomposed until it flows out of the catalytic bed.

[0072] The flow equalizing holes in the embodiment of the present application are uniformly distributed on the partition and flow equalizing plate 40, which is beneficial to minimizing the pressure drop as much as possible.

[0073] It should be noted that a chemical reaction type catalyst is arranged in the front bed catalytic chamber B1. The atomized hydrogen peroxide injected by the atomizing injector 30 undergoes an oxidation-reduction reaction and a catalytic decomposition reaction simultaneously under the action of the chemical reaction type catalyst in the front bed catalytic chamber B1. Exemplarily, the liquid hydrogen peroxide propellant reacts on the surface of the chemical reaction type catalyst to generate high-temperature water vapor and water vapor, and at the same time releases a large amount of heat. The high-temperature gas in turn heats the hydrogen peroxide propellant droplets to vaporize them into gaseous hydrogen peroxide vapor, thereby improving the catalytic decomposition efficiency.

[0074] It should be understood that the chemical reaction type catalyst in the embodiments of the present application refers to a chemical substance with high chemical reaction activity that can directly undergo an oxidation-reduction reaction with hydrogen peroxide, such as metal hydrides. For example, sodium borohydride, potassium permanganate particles, sodium permanganate, or manganese oxide, etc. can be used as catalytic active components. The carriers of these catalytic active components can be selected from carriers with high specific surface area, mechanical properties, and temperature resistance. Exemplarily, the carrier can be at least one of a particulate carrier (such as alumina, magnesia, titanium oxide, porous glass, activated carbon, nickel metal), a honeycomb ceramic carrier (such as cordierite, silicon carbide, etc. ceramics), or a porous foam carrier (such as nickel foam, aluminum, copper, titanium, or alumina).

[0075] Furthermore, a mesh-based catalyst is provided in the rear bed catalytic chamber B2. The mesh-based catalyst is formed by stacking and pressing together metal mesh sheets plated with catalytic active components on the surface. The stacking and pressing of the metal mesh sheets form tortuous channels for the flow of hydrogen peroxide; the mesh-based catalyst has a high bed load and catalytic reaction activity, a long service life, is stable and reliable, can be used for a long time, and the service life can reach 500 - 2000 seconds.

[0076] Taking hydrogen peroxide propellant as an example, the liquid hydrogen peroxide passing through the chemical reaction type catalyst undergoes a partial decomposition reaction but is not completely decomposed. At this time, the main components are the decomposed oxygen and water vapor, as well as the incompletely decomposed hydrogen peroxide vapor. When the incompletely decomposed hydrogen peroxide vapor flows through the tortuous channels inside the mesh-based catalyst, it comes into contact with the surface of the metal wire mesh and undergoes a catalytic decomposition reaction. The hydrogen peroxide is catalytically decomposed into oxygen and water vapor and releases heat to heat the catalytic bed, thereby accelerating the catalytic decomposition rate. As the flow progresses until complete decomposition, it decomposes into high-temperature water vapor and oxygen, thereby achieving the complete decomposition of gelled hydrogen peroxide and significantly improving the catalytic decomposition efficiency.

[0077] It should be understood that the catalytic active components of the mesh-based catalyst in the embodiments of the present application as catalysts for the catalytic decomposition of hydrogen peroxide can be selected from at least one of silver, platinum, palladium, iridium, or ruthenium; the base material of the metal wire mesh can be nickel, palladium, or stainless steel, etc.

[0078] It should be noted that the chemical reaction type catalyst provided in the front bed catalytic chamber B1 can undergo a violent oxidation-reduction reaction and a catalytic decomposition reaction with the hydrogen peroxide propellant to achieve a rapid start and rapid temperature rise of the catalytic bed 100, and promote a rapid increase in the decomposition efficiency; the partially decomposed hydrogen peroxide and its decomposition gas in the front bed catalytic chamber B1 enter the rear bed catalytic chamber B2, and after coming into contact with the surface of the mesh-based catalyst provided in the rear bed catalytic chamber B2, a stable catalytic decomposition reaction occurs, further improving the catalytic decomposition efficiency, achieving the complete decomposition of hydrogen peroxide, and improving the bed load capacity of the catalytic bed 100.

[0079] Therefore, the purpose of comprehensively using chemical reaction catalysts and mesh-based catalysts in the catalytic bed 100 is to utilize the advantageous ranges of the two catalysts. The chemical reaction catalysts achieve the rapid startup and rapid temperature rise of the catalytic bed 100, and the mesh-based catalysts can improve the decomposition efficiency and bed loading capacity of the catalytic bed 100.

[0080] Reference Figure 1 As shown, in the embodiment of the present application, an annular support ring 70 is further provided in the front bed catalytic chamber B1. The outer wall of the support ring 70 fits with the front bed catalytic chamber B1. The two ends of the support ring 70 along the axial direction are respectively connected to the atomizing injector 30 and the partition flow equalizing plate 40, so as to improve the loading stability of the chemical reaction catalyst and the overall structural strength of the catalytic bed 100.

[0081] In some embodiments of the present application, the catalytic bed 100 further includes a filter screen (not shown), and the filter screen is arranged on the front and rear bed partition flow equalizing plate 40 to prevent the chemical reaction catalyst from entering the rear bed catalytic chamber B2.

[0082] Continue to refer to Figure 1 and Figure 2 , in some embodiments, the catalytic bed 100 further includes a direct current injection panel 50 and an outlet flow equalizing plate 60; the two ends of the catalytic bed housing 10 are respectively provided with a feed inlet 11 and a discharge outlet 12; the direct current injection panel 50 is arranged in the injection chamber A and is connected to the catalytic bed housing 10. A number of feed through holes communicating with the feed inlet 11 are provided on the direct current injection panel 50, and the capillary injection tube 20 is communicated with the feed through holes; the outlet flow equalizing plate 60 is arranged in the rear bed catalytic chamber B2 and is connected to the catalytic bed housing 10. A number of discharge through holes communicating with the discharge outlet 12 are provided on the outlet flow equalizing plate 60.

[0083] In this embodiment, the two ends of the catalytic bed housing 10 are respectively provided with a feed inlet 11 and a discharge outlet 12. The feed inlet 11 is used to communicate with the conveying device 200 of the propulsion system 1000. The direct current injection panel 50 is arranged in the injection chamber A and is arranged opposite to the atomizing injector 30. A number of feed through holes communicating with the feed inlet 11 are provided on the direct current injection panel 50, and the capillary injection tube 20 is communicated with the feed through holes, so that the gel hydrogen peroxide supplied by the conveying device 200 enters the direct current injection panel 50 after passing through the feed inlet 11, and then is converted into atomized liquid hydrogen peroxide under the action of the capillary injection tube 20 and the atomizing injector 30 and enters the catalytic chamber B for catalytic decomposition. The outlet flow equalizing plate 60 is arranged in the rear bed catalytic chamber B2 and is connected to the catalytic bed housing 10. A number of discharge through holes communicating with the discharge outlet 12 are provided on the outlet flow equalizing plate 60. The discharge outlet 12 is used to communicate with the combustion chamber 300 of the propulsion system 1000 to supply the gas obtained after catalytic decomposition into the combustion chamber 300 for combustion ignition.

[0084] Reference Figure 1 、Figure 8 and Figure 9 as shown Figure 8 is a partial structural schematic view of a perspective of a catalytic bed housing 10 provided according to an embodiment of the present application; Figure 9 is a partial structural schematic view of another perspective of a catalytic bed housing 10 provided according to an embodiment of the present application;

[0085] To increase the initial reaction rate of the catalytic bed, in some embodiments, a heat exchange cavity C is further formed in the catalytic bed housing 10. The heat exchange cavity C is disposed circumferentially around the injection chamber A and the catalytic chamber B for circulating a heat exchange medium to preheat the catalyst in the catalytic bed 100.

[0086] By using the heat exchange cavity C to circumferentially wrap the injection chamber A and the catalytic chamber B, before the catalytic bed 100 starts to work, a preheated fluid heat exchange medium can be introduced into the heat exchange cavity C. For example, the catalyst in the catalytic bed 100 can be preheated by a high-temperature liquid or gas (50 - 200 °C) to increase the reaction rate between the catalyst and hydrogen peroxide and improve the starting performance of the catalytic bed 100 (reduce the starting delay time and improve the catalytic efficiency).

[0087] In addition, when the catalytic bed 100 is operating normally, the temperature of the heat exchange medium is significantly lower than the adiabatic decomposition temperature of hydrogen peroxide (for example, the adiabatic decomposition temperature of hydrogen peroxide is 900 - 950 °C). Therefore, the heat exchange medium can also cool the housing of the catalytic bed 100 at this time to prevent the catalytic bed housing 10 from failing due to overheating.

[0088] Further, a heat exchange medium inlet 13 and a heat exchange medium outlet 14 respectively communicating with the heat exchange cavity C are provided on the catalytic bed housing 10 for the heat exchange medium to flow into or out of the heat exchange cavity C.

[0089] Refer to Figure 8 and Figure 9 , in some embodiments, to improve the heat exchange efficiency, a plurality of fins 15 are provided in the heat exchange cavity C. The plurality of fins 15 are circumferentially spaced and arranged along the circumference of the catalytic chamber B to divide the heat exchange cavity C into a plurality of heat exchange channels, which is conducive to strengthening convective heat transfer and effectively improving the heat exchange efficiency.

[0090] Refer to Figure 11 as shown Figure 11It is a schematic diagram of the modules of the propulsion system 1000 provided according to the embodiments of the present application. Another embodiment of the present application provides a propulsion system 1000, which includes the catalytic bed 100 as described above, and also includes a conveying device 200, a combustion chamber 300, and a nozzle 400; the conveying device 200 is communicated with the injection chamber A, and the conveying device 200 can convey gel hydrogen peroxide to the catalytic bed 100; the combustion chamber 300 is communicated with the catalytic chamber B to receive the high-temperature gas generated after the catalytic decomposition of gel hydrogen peroxide and provide a space for gas combustion; the nozzle 400 is communicated with the combustion chamber 300 to convert the thermal energy generated by the combustion of the high-temperature and high-pressure gas in the combustion chamber 300 into kinetic energy.

[0091] In summary, through the design of the catalytic bed 100 and the propulsion system 1000 in the embodiments of the present application, gel hydrogen peroxide is atomized and injected from the gel state into liquid droplets under the synergistic action of the capillary injection tube 20 and the atomizing injector 30, so as to quickly diffuse in the catalytic chamber B and fully contact with the catalyst, and is completely decomposed into gas after passing through the front-bed catalytic chamber B1 and the rear-bed catalytic chamber B2, which significantly improves the catalytic decomposition efficiency of the catalytic bed 100 and is conducive to promoting the practical application process of gel hydrogen peroxide in the aerospace propulsion system.

[0092] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limitations of the present invention. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A catalytic bed (100) for gel hydrogen peroxide, characterized in that, Comprising: A catalytic bed housing (10) formed with an injection chamber (A) and a catalytic chamber (B); A capillary injection tube (20) disposed in the injection chamber (A) for receiving gelled hydrogen peroxide and converting the gelled hydrogen peroxide into liquid hydrogen peroxide; An atomizing injector (30) disposed in the injection chamber (A) and connected to the catalytic bed housing (10), and the atomizing injector (30) is in communication with the capillary injection tube (20) and the catalytic chamber (B); Wherein, the atomizing injector (30) is configured to atomize the liquid hydrogen peroxide conveyed by the capillary injection tube (20) and convey the atomized hydrogen peroxide into the catalytic chamber (B) for catalytic decomposition.

2. The catalytic bed (100) according to claim 1, wherein The atomizing injector (30) is provided with a first injection hole (30A) and a second injection hole (30B), and the first injection hole (30A) and the second injection hole (30B) are respectively in communication with the corresponding capillary injection tube (20); Wherein, the axis of the first injection hole (30A) intersects with the axis of the second injection hole (30B) so that the liquid hydrogen peroxide flowing out through the first injection hole (30A) and the second injection hole (30B) collides to atomize the liquid hydrogen peroxide.

3. The catalytic bed (100) according to claim 2, wherein The included angle between the axis of the first injection hole (30A) and the axis of the second injection hole (30B) is 20 to 100°; and / or Both the first injection holes (30A) and the second injection holes (30B) are multiple in number. The multiple first injection holes (30A) are spaced apart and arranged in a ring in a first area of the atomizing injector (30), and the multiple second injection holes (30B) are spaced apart and arranged in a ring in a second area of the atomizing injector (30). The first area is located inside the second area in the radial direction of the atomizing injector (30), and the first injection holes (30A) and the second injection holes (30B) are arranged in one-to-one correspondence.

4. The catalytic bed (100) according to claim 1, wherein The catalytic bed housing (10) is provided with a high-pressure air inlet (10A), and the high-pressure air inlet (10A) is in communication with the injection chamber (A) for supplying high-pressure gas to the injection chamber (A); The atomizing injector (30) is provided with a third injection hole (30C) and a fourth injection hole (30D). The third injection hole (30C) is in communication with the capillary injection tube (20), and the fourth injection hole (30D) is in communication with the injection chamber (A); Wherein, the axis of the fourth injection hole (30D) intersects with the axis of the third injection hole (30C) so that the high-pressure gas ejected through the fourth injection hole (30D) can collide with the liquid hydrogen peroxide ejected through the third injection hole (30C) to atomize the liquid hydrogen peroxide.

5. The catalytic bed (100) according to claim 4, wherein a plurality of high-pressure air inlets (10A) are provided, and the plurality of high-pressure air inlets (10A) are annularly arranged on the inner wall of the injection chamber (A); the included angle between the axis of the fourth injection hole (30D) and the axis of the third injection hole (30C) is 20 to 100°; and / or the fourth injection holes (30D) are symmetrically arranged, and the third injection hole (30C) is arranged between two paired fourth injection holes (30D).

6. The catalytic bed (100) according to any one of claims 1 to 5, wherein the catalytic bed (100) further includes a partition and flow equalizing plate (40), and the partition and flow equalizing plate (40) is arranged in the catalytic chamber (B) and connected to the catalytic bed housing (10) to divide the catalytic chamber (B) into a front bed catalytic chamber (B1) and a rear bed catalytic chamber (B2); a plurality of flow equalizing through holes are formed in the partition and flow equalizing plate (40), and the flow equalizing through holes communicate the front bed catalytic chamber (B1) and the rear bed catalytic chamber (B2); the front bed catalytic chamber (B1) is located between the injection chamber (A) and the rear bed catalytic chamber (B2), and a chemical reaction type catalyst is arranged in the front bed catalytic chamber (B1), and a mesh-based catalyst is arranged in the rear bed catalytic chamber (B2) to catalytically decompose the atomized hydrogen peroxide injected by the atomizing injector (30) in stages.

7. The catalytic bed (100) according to claim 6, characterized in that, The catalytic bed (100) further includes a direct current injection panel (50) and an outlet flow equalizing plate (60); feeding ports (11) and discharging ports (12) are respectively formed at two ends of the catalytic bed housing (10); the direct current injection panel (50) is arranged in the injection chamber (A) and connected to the catalytic bed housing (10), and a plurality of feeding through holes capable of communicating with the feeding port (11) are formed in the direct current injection panel (50), and the capillary injection tubes (20) are communicated with the feeding through holes; the outlet flow equalizing plate (60) is arranged in the rear bed catalytic chamber (B2) and connected to the catalytic bed housing (10), and a plurality of discharging through holes capable of communicating with the discharging port (12) are formed in the outlet flow equalizing plate (60).

8. The catalytic bed (100) according to claim 1, characterized in that, The catalytic bed housing (10) further forms a heat exchange chamber (C), and the heat exchange chamber (C) surrounds the injection chamber (A) and the catalytic chamber (B) in the circumferential direction for circulating a heat exchange medium to preheat the catalyst in the catalytic bed (100).

9. The catalytic bed (100) according to claim 8, characterized in that, a heat exchange medium inlet (13) and a heat exchange medium outlet (14) respectively communicating with the heat exchange chamber (C) are formed on the catalytic bed housing (10) for the heat exchange medium to flow into or out of the heat exchange chamber (C); and / or a plurality of fins (15) are arranged in the heat exchange chamber (C), and the plurality of fins (15) are annularly arranged at intervals along the circumferential direction of the catalytic chamber (B) to divide the heat exchange chamber (C) into a plurality of heat exchange channels.

10. A propulsion system (1000), characterized in that, It includes a catalytic bed (100) as described in any one of claims 1 to 9, and further includes a conveying device (200), a combustion chamber (300), and a nozzle (400); The conveying device (200) is communicated with the injection chamber (A) to convey gel hydrogen peroxide to the catalytic bed (100); The combustion chamber (300) is communicated with the catalytic chamber (B) to receive the gas generated after the catalytic decomposition of gel hydrogen peroxide; The nozzle (400) is communicated with the combustion chamber (300) to convert the thermal energy generated by the gas in the combustion chamber (300) into kinetic energy.

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