Granule for end face combustion solid-liquid fuel gas generator

Abstract

The invention provides a grain for an end face combustion solid-liquid fuel gas generator. The grain comprises a body. One end of the body is of a conical surface structure, and a group of blades for improving the combustion rate of the grain are arranged in the body; the body and the blades are made of the same material; a combustion medium is fully nested in the body. The device is simple and reasonable in structural design, solves the problem that the shape of a combustion surface is difficult to maintain in the combustion process of the paraffin-based grain end face, meets the supply requirement of high-flow rich combustion gas, and is suitable for popularization and application.

Description

Technical Field

[0001] The present invention relates to the technical field of gas generators, in particular to a charge column for an end-face combustion solid-liquid gas generator. Background Art

[0002] Solid-liquid gas generators use separately stored solid-liquid two-phase propellants, generally in the form of a combination of solid fuel and liquid oxidizer. Therefore, solid-liquid gas generators combine many advantages of liquid gas generators and solid gas generators, such as relatively simple structure, excellent safety, repeatable restart, adjustable flow, green and non-toxic, and low cost. Based on the above advantages, solid-liquid gas generators can be widely used in commercial and other fields as a fuel-rich gas supply system. Among them, solid-liquid gas generators using end-face combustion are an important structural form. This combustion organization form has attracted the attention of researchers due to its advantages of constant combustion surface and relatively stable combustion conditions.

[0003] Similar to solid-liquid rocket engines, traditional end-burning solid-liquid gas generators typically use polymers such as hydroxyl-terminated polybutadiene, polyethylene, and polymethyl methacrylate as solid fuel. Due to the low recession rate of traditional solid combustion, end-burning solid-liquid gas generators are limited by the difficulty of producing large flows of rich fuel gas. To provide abundant rich fuel gas, increasing the diameter of the grain and combining it with swirl injection can increase the burning surface area and improve the recession rate. This results in the disadvantage of increasing the size and weight of the gas generator structure. Furthermore, due to the influence of the swirl field, the burning surface of the grain often changes shape, affecting the stability of the combustion conditions.

[0004] Therefore, paraffin fuel, as a high-degradation fuel, shows its unique advantages in application in solid-liquid gas generators. Its degradation rate is several times that of traditional fuels (such as hydroxyl-terminated polybutadiene), which gives it the potential to achieve a large flow of rich fuel gas supply with only a smaller grain diameter, effectively solving the difficulty of increasing the gas flow of end-fired solid-liquid gas generators and improving volume utilization. At the same time, the purchase and processing costs of paraffin are low, and the testing and use costs of gas generators can be greatly reduced. In addition, the combustion calorific value of paraffin is basically the same as that of hydroxyl-terminated polybutadiene, and its liquefied liquid film has excellent thermal protection capabilities.

[0005] However, the mechanical properties of paraffin fuel are significantly inferior to those of hydroxyl-terminated polybutadiene, making it susceptible to softening and collapse during prolonged combustion. While adding binders and hardeners to paraffin improves mechanical properties, this also negates much of the advantage of a high rate of decay. During end-face combustion, paraffin fuel is also affected by the fluidity of the surface liquid film, making it more difficult to maintain its end-face structure. Especially when combined with swirl injection, the surface structure often becomes uneven, significantly altering the combustion surface area and causing deviations in actual operating conditions.

[0006] These issues hinder the further development of paraffin-based fuels and must be addressed if they are to be used in end-fired solid-liquid gas generators. However, current research on improving the performance of end-fired solid-liquid gas generators is still very scarce. Traditional grain design cannot effectively address the problems encountered in end-fired combustion, and from a grain material perspective alone, it is difficult to find a grain material or additive that can achieve both high regression rates and good mechanical properties.

[0007] In summary, it is necessary to make further innovations to the existing technologies. Summary of the Invention

[0008] In response to the technical problems existing in the above-mentioned background technology, the present invention proposes a propellant column for end-face combustion solid-liquid gas generator, which has a simple and reasonable structural design, solves the problem that the shape of the combustion surface is difficult to maintain during the end-face combustion of paraffin-based propellants, and meets the supply demand of large-flow rich fuel gas.

[0009] In order to solve the above technical problems, the present invention provides a charge for an end-face combustion solid-liquid gas generator, which includes a main body; one end of the main body is a conical structure, and a group of blades for increasing the combustion rate of the charge are arranged inside; the material selected for the main body and the blades is consistent; and the combustion medium is fully nested inside the main body.

[0010] The grain used for the end-face combustion solid-liquid gas generator, wherein: the cone angle of the conical surface structure at one end of the grain is greater than or equal to 45°.

[0011] The charge for the end-face combustion solid-liquid gas generator, wherein: the shape of the blades conforms to the Archimedean spiral equation.

[0012] The charge for the end-face combustion solid-liquid gas generator, wherein: the materials of the body and the blades can both be ABS material; the ABS material is composed of 43% acrylonitrile, 50% butadiene and 7% styrene in mass percentage.

[0013] The charge column for end-face combustion solid-liquid gas generator, wherein: the material of the body and the blades can also be made of aluminum-magnesium alloy; the aluminum-magnesium alloy includes AlSi 10 Mg and Al 90 Mg 10 .

[0014] The powder column for the end-face combustion solid-liquid gas generator, wherein: the combustion medium (3) includes paraffin-based fuel; the paraffin-based fuel is composed of 58% by mass of low-melting point paraffin, 20% by mass of high molecular wax, 10% by mass of adhesive, 10% by mass of hardener and 2% by mass of carbon powder.

[0015] The powder column used for the end-face combustion solid-liquid gas generator, wherein the mass fraction of the paraffin-based fuel is higher than 75%.

[0016] The powder column used for the end-face combustion solid-liquid gas generator, wherein: the combustion medium also includes aluminum powder and magnesium powder.

[0017] The grain used for the end-face combustion solid-liquid gas generator, wherein: the ratio of the length to the diameter of the grain is between 0.1-5.0.

[0018] The grain used for the end-face combustion solid-liquid gas generator, wherein the molding method of the grain includes at least one of the following: casting or additive manufacturing.

[0019] By adopting the above technical solution, the present invention has the following beneficial effects:

[0020] The invention has a simple and reasonable grain structure design for an end-face combustion solid-liquid gas generator, solves the problem that the shape of the combustion surface of the paraffin-based grain of the end-face combustion solid-liquid gas generator is difficult to maintain, and greatly improves the combustion rate of the paraffin-based fuel by providing spiral blades that conform to the Archimedean spiral equation, so that the solid-liquid gas generator can provide a larger flow of rich fuel gas with a smaller combustion chamber volume, effectively improving the volume utilization rate; secondly, the use of ABS or aluminum-magnesium alloy bodies and blades greatly improves the mechanical properties of the grain, while improving the safety of the solid-liquid gas generator, making it suitable for promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1This is a schematic structural diagram of a charge column used in a solid-liquid gas generator according to the present invention;

[0023] Figure 2 This is a front view of a charge column used for a solid-liquid gas generator according to the present invention;

[0024] Figure 3 AA sectional view of a charge for a solid-liquid gas generator according to the present invention;

[0025] Figure 4 It is a BB-cross-sectional view of a charge for a solid-liquid gas generator according to the present invention;

[0026] Figure 5 This is a comparison chart of the test results of the regression rate of the grain used in the solid-liquid gas generator of the present invention and the traditional grain. DETAILED DESCRIPTION

[0027] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0028] The present invention will be further explained below with reference to specific embodiments.

[0029] like Figure 1-4 As shown, this embodiment provides a charge for an end-face combustion solid-liquid gas generator, comprising a body 1 , blades 2 and a combustion medium 3 .

[0030] One end of the main body 1 has a conical structure with a cone angle greater than or equal to 45 degrees, which is used to increase the burning surface area and reduce the diameter of the charge; a group of blades 2 for increasing the burning rate of the charge are arranged in the main body 1; the shape of the blade 2 conforms to the Archimedean spiral equation to construct the initial profile and then extrapolate the blade thickness to form; and a combustion medium 3 is nested between the main body 1 and the blade 2, and the combustion medium 3 includes paraffin-based fuel, and the mass fraction of the paraffin-based fuel is higher than 75%; the combustion medium may also include aluminum powder and magnesium powder; the mass proportion of some low-melting-point paraffin and polymer wax can be replaced, and the mass percentage of aluminum powder and magnesium powder is less than or equal to 25%, which is used to increase the combustion calorific value of the combustion medium 3.

[0031] The material of the body 1 and the blade 2 is the same, both made of ABS or aluminum-magnesium alloy; the aluminum-magnesium alloy includes AlSi 10 Mg and Al 90 Mg 10 .

[0032] Among them, the thickness of the blade 2 is 0.5-5mm, and it rotates outward 4-10 times along the radial direction of the grain. The rotation direction of the blade 2 matches the injection method of the oxidant injector of the solid-liquid gas generator. If the injector injects clockwise, the rotation direction of the blade 2 is opposite to the swirl injection direction, which can further increase the grain retreat rate.

[0033] In this embodiment, the body 1 is 1.5 mm thick and 104 mm long; the blades 2 are 1.2 mm thick. The profile of the blades 2 satisfies the Archimedean spiral equation r = θ / 50, where r represents the radius in polar coordinates and θ represents the arc in polar coordinates. The grain's outer diameter is 84 mm, and the grain length-to-diameter ratio is approximately 1.24. The body 1 and blades 2 are constructed from ABS, a material with a low burning rate and high mechanical properties. The ABS material is composed of 43% acrylonitrile, 50% butadiene, and 7% styrene by weight. The combustion medium 3 includes a paraffin-based fuel composed of 58% low-melting-point paraffin wax, 20% polymer wax, 10% binder, 10% hardener, and 2% carbon powder. The mass fraction of the paraffin-based fuel ranges from 75% to 95%. To increase the calorific value of the paraffin-based fuel, high-performance materials such as aluminum powder or magnesium powder may be added to the combustion medium 3.

[0034] The length-to-diameter ratio of the drug column of the present invention is between 0.1 and 5.0; and the molding method of the drug column of the present invention includes at least one of the following: casting or additive manufacturing technology.

[0035] This example is based on a ground test bench for a solid-liquid gas generator with an oxidant flow rate of 10 g / s. The rotation direction of the grain blades is set to clockwise, which can achieve excellent experimental performance. Figure 5 As shown, the retreat rate of the grain is greatly improved on the basis of paraffin-based fuel.

[0036] In one embodiment of the present invention, the main body 1 and the blades 2 are integrally formed using additive manufacturing technology. The rear body 1 and the blades 2 are used as molds, and the combustion medium 3 is poured by casting. Finally, it is ensured that the charge is integrally formed, and there is no gap between the main body 2, the blades 3 and the combustion medium 3.

[0037] By combining the advantages of high-degradation paraffin-based fuels with high-mechanical-property materials such as ABS, this invention not only solves the problem of paraffin-based grains having difficulty maintaining their combustion surface shape during end-face combustion, but also meets the demand for high-flow, fuel-rich gas supply in end-face combustion solid-liquid gas generators. The spirally arranged blades primarily increase the combustion rate of the paraffin-based fuel, effectively improving the engine's volume utilization. Furthermore, the use of ABS material for the main body 1 and blades 2 significantly enhances the mechanical properties of the grain, strengthens the ability to maintain the combustion surface structure, and improves the safety of solid-liquid rocket engines.

[0038] The present invention has a simple and reasonable structural design, solves the problem that the shape of the burning surface is difficult to maintain during the combustion of the end face of the paraffin-based charge, and meets the supply demand for a large flow of rich fuel gas.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A charge for an end-fired solid-liquid gas generator, characterized by: The charge comprises a body (1); one end of the body (1) is a conical structure, and a group of blades (2) for increasing the burning rate of the charge are arranged inside; the material selected for the body (1) and the blades (2) is consistent; and a combustion medium (3) is fully nested inside the body (1).

2. The charge for the end-fired solid-liquid gas generator according to claim 1, characterized in that: The cone angle of the conical structure at one end of the medicine column is greater than or equal to 45°.

3. The charge for an end-fired solid-liquid gas generator according to claim 1, characterized in that: The shape of the blade (2) conforms to the Archimedean spiral equation.

4. The charge for an end-fired solid-liquid gas generator according to claim 1, characterized in that: The body (1) and the blades (2) can both be made of ABS material; the ABS material is composed of 43% by mass of acrylonitrile, 50% by mass of butadiene, and 7% by mass of styrene.

5. The charge for the end-fired solid-liquid gas generator according to claim 1, characterized in that: The material of the body (1) and the blade (2) can also be aluminum-magnesium alloy; the aluminum-magnesium alloy includes AlSi 10 Mg and Al 90 Mg 10 .

6. The charge for an end-fired solid-liquid gas generator according to claim 1, characterized in that: The combustion medium (3) includes paraffin-based fuel; the paraffin-based fuel is composed of 58% by mass of low-melting-point paraffin, 20% of high-molecular wax, 10% of adhesive, 10% of hardener and 2% of carbon powder.

7. The charge for the end-fired solid-liquid gas generator according to claim 6, characterized in that: The mass fraction of the paraffin-based fuel is higher than 75%.

8. The charge for an end-fired solid-liquid gas generator according to claim 1, characterized in that: The combustion medium (3) may also include aluminum powder and magnesium powder, and the mass percentage of the aluminum powder to the magnesium powder is less than or equal to 25%.

9. The charge for an end-fired solid-liquid gas generator according to claim 1, characterized in that: The length to diameter ratio of the drug column is between 0.1 and 5.

0.

10. The charge for the end-fired solid-liquid gas generator according to claim 1, characterized in that: The forming method of the drug column includes at least one of the following: casting or additive manufacturing.

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