Metal fuel propellant and method of making same

Abstract

The application provides a metal fuel propellant and a preparation method thereof, and belongs to the technical field of solid propellants. 3 Compared with traditional aluminum-based propellants, the zirconium-based propellant has a greater density, and the increase of the density can not only increase the volume specific impulse of the propellant, but also increase the speed increment of a missile, so that the zirconium-based propellant has more excellent energy characteristics and can be applied to small volume engines; the application of zirconium hydride as a fuel additive increases the hydrogen content in the fuel, reduces the flame temperature of the propellant and improves the specific impulse of the propellant; the application of zirconium hydride as a fuel additive has good resistance to direct oxidation of perchlorate and can improve the energy characteristics and combustion performance of the zirconium-based propellant; and the application of aluminum powder as a fuel additive has high combustion heat value and good oxidation performance and can promote the combustion reaction of the zirconium powder.

Description

Technical Field

[0001] This invention belongs to the field of solid propellant technology, specifically relating to a metallic fuel propellant and its preparation method. Background Technology

[0002] Zirconium is an important new type of metallic material widely used in demanding fields such as chemical equipment, nuclear reactor components, aerospace technology, and medical devices. It is also a novel high-density composite propellant additive. Compared to traditional aluminum-based propellants, zirconium-based propellants can achieve a density of 4.0~5.0 g / cm³. 2 The density of zirconium-based propellants is approximately 1.6 times that of aluminum-based propellants. Increasing propellant density can improve both the missile's payload and the propellant's specific impulse. Under the same size conditions, zirconium powder exhibits superior combustion performance compared to aluminum powder, and the two-phase flow loss of zirconium-based propellants is significantly lower than that of aluminum-based propellants. Therefore, zirconium-based propellants have advantages over aluminum-based propellants, including higher bulk density, higher specific impulse, better combustion performance, lower two-phase flow loss, and higher energy characteristics. They are expected to be widely used in space propulsion, underwater propulsion, and other fields, making them a highly promising new type of high-density metallic fuel propellant with significant practical value.

[0003] Metallic fuel propellants are a crucial component of water ramjet engines and serve as the power source for various water ramjet engines, including those used in hypersonic torpedo cruise propulsion systems. Water ramjet engines utilize metallic fuels as combustion agents, with external seawater acting as both the primary oxidizer and working fluid. This technology is essential for enhancing the performance of next-generation hypersonic torpedoes and improving their penetration capabilities during the active phase. Furthermore, improving the energy characteristics of the propellant is a necessary condition for achieving longer ranges and faster penetration capabilities in next-generation high-performance torpedoes.

[0004] Chinese patent publication number CN113996307A reports a catalyst support for the preparation of high-energy-density fuels by zirconium, as well as its preparation method and application. This patent uses a zirconium source to prepare a catalyst that converts lignin into high-energy-density fuels such as bicyclic alkanes and tricyclic alkanes, which greatly improves the added value of lignin applications. However, it does not take full advantage of zirconium as a metallic material in terms of volume density and energy characteristics. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a metallic fuel propellant and a method for preparing the same. The metallic fuel propellant prepared by the present invention has the characteristics of good combustion performance, large volumetric impulse, and high energy characteristics.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0007] The present invention provides a metallic fuel propellant comprising fuel, fuel additives and an oxidant, wherein the fuel comprises metallic zirconium powder, the fuel additives comprise metallic aluminum powder and zirconium hydride, and the oxidant comprises perchlorate.

[0008] Preferably, the metallic fuel propellant comprises the following components in weight percentage:

[0009] Zirconium metal powder: 50~70%;

[0010] Zirconium hydride: 8~12%;

[0011] Aluminum powder: 10~30%;

[0012] Perchlorate: 8~12%.

[0013] Preferably, the zirconium powder includes ultrafine zirconium powder and conventional zirconium powder; the particle size of the ultrafine zirconium powder is 1~5μm, and the particle size of the conventional zirconium powder is 40~100μm.

[0014] Preferably, the mass ratio of ultrafine zirconium powder in the zirconium metal powder is ≤60%.

[0015] Preferably, the zirconium hydride has a particle size of 10~100μm.

[0016] Preferably, the particle size of the aluminum powder is 10~100μm.

[0017] Preferably, the perchlorate includes potassium perchlorate or ammonium perchlorate.

[0018] The present invention also provides a method for preparing the metallic fuel propellant described in the above technical solution, comprising the following steps:

[0019] The fuel, fuel additive, and oxidant are mixed, pressed, and dried in sequence to obtain the metallic fuel propellant.

[0020] Preferably, the pressing is performed using a pressing machine, and the pressing pressure is preferably 200 MPa.

[0021] This invention provides a metallic fuel propellant, comprising fuel, fuel additives, and an oxidant. The fuel includes zirconium powder, the fuel additives include aluminum powder and zirconium hydride, and the oxidant includes perchlorate. This invention uses zirconium powder as the fuel, which has extremely high energy density, effectively improving the propellant's specific impulse and making it suitable for small-volume engines. This invention uses ZrH2 as the fuel additive, which has good resistance to direct oxidation by perchlorate and can independently dehydrogenate to produce H2 and metallic Zr, reducing the gas molecular mass, significantly improving the fuel's energy characteristics and combustion performance, lowering the propellant's combustion temperature, and further increasing the propellant's specific impulse. This invention uses aluminum powder as the fuel additive, enhancing the combustion process, making combustion more complete, improving combustion efficiency, and thus increasing the propellant's thrust and combustion rate.

[0022] This invention also provides a method for preparing the metallic fuel propellant described in the above technical solution, comprising the following steps: sequentially mixing, pressing, and drying fuel, fuel additives, and oxidant to obtain the metallic fuel propellant. This invention employs a pressing molding process, which is simple to operate and has a relatively simplified process flow, enabling efficient production of large quantities of solid propellant products. Detailed Implementation

[0023] The present invention provides a metallic fuel propellant comprising fuel, fuel additives and an oxidant, wherein the fuel comprises metallic zirconium powder, the fuel additives comprise metallic aluminum powder and zirconium hydride, and the oxidant comprises perchlorate.

[0024] In this invention, unless otherwise specified, all components are commercially available products well known to those skilled in the art.

[0025] The metallic fuel propellant provided by this invention preferably comprises 50-70% zirconium powder by mass percentage, more preferably 50-60%, and even more preferably 53%. In this invention, the zirconium powder preferably comprises ultrafine zirconium powder and conventional zirconium powder; the particle size of the ultrafine zirconium powder is preferably 1-5 μm, more preferably 1-3 μm; the particle size of the conventional zirconium powder is preferably 40-100 μm, more preferably 60-80 μm. In this invention, the mass ratio of ultrafine zirconium powder in the metallic zirconium powder is preferably ≤60%. In this invention, the metallic zirconium powder has extremely high energy density, effectively improving the specific impulse of the propellant, and is suitable for small-volume engines. In this invention, the ultrafine zirconium powder replaces part of the conventional zirconium powder to obtain a new composite zirconium powder with a new particle density. The ultrafine zirconium powder can be fully mixed with other components in the propellant, increasing the density of the propellant. During propellant combustion, the ultrafine zirconium powder can provide a larger specific surface area, enhancing the combustion reaction and promoting a faster combustion rate. Conventional zirconium powder helps to provide a more stable combustion process.

[0026] The metallic fuel propellant provided by this invention preferably comprises 8-12% zirconium hydride, more preferably 9-11%, by mass percentage. In this invention, the particle size of the zirconium hydride is preferably 10-100 μm. In this invention, the zirconium hydride can be used as a fuel additive; ZrH2 has good resistance to direct oxidation by perchlorate, can independently dehydrogenate to generate H2 and metallic Zr, can reduce the molecular weight of the gas, significantly improves the energy characteristics and combustion performance of the fuel, lowers the combustion temperature of the propellant, and further increases the specific impulse of the propellant.

[0027] The metallic fuel propellant provided by the present invention preferably comprises 10-30% aluminum powder, more preferably 20-30%, by mass percentage. In the present invention, the particle size of the aluminum powder is preferably 10-100 μm. In the present invention, the aluminum powder can act as a fuel additive to enhance the combustion process, making combustion more complete and improving combustion efficiency, thereby increasing the thrust and combustion rate of the propellant.

[0028] The metal fuel propellant provided by the present invention preferably comprises 8-12% perchlorate, more preferably 9-11% by mass percentage. In the present invention, the perchlorate preferably comprises potassium perchlorate or ammonium perchlorate.

[0029] The present invention also provides a method for preparing the metallic fuel propellant described in the above technical solution, comprising the following steps:

[0030] The fuel, fuel additive, and oxidant are mixed, pressed, and dried in sequence to obtain the metallic fuel propellant.

[0031] In this invention, the pressing is preferably carried out using a pressing machine, and the pressing pressure is preferably 200 MPa.

[0032] The present invention does not impose any special limitations on the mixing, pressing and drying processes, and any processes well known to those skilled in the art can be used.

[0033] This invention employs a compression molding process, which is simple to operate and has a relatively simplified process flow, enabling the efficient production of large quantities of solid propellant products.

[0034] To further illustrate the present invention, the following detailed description of the metal fuel propellant and its preparation method provided by the present invention is provided in conjunction with embodiments, but these should not be construed as limiting the scope of protection of the present invention.

[0035] Example 1

[0036] The mass ratio of each component is as follows: zirconium metal powder (Zr): 53.3%; zirconium hydride (ZrH2): 9.8%; aluminum metal powder (Al): 26.9%; ammonium perchlorate (AP): 10.0%.

[0037] The aforementioned metallic zirconium powder is a composite zirconium powder composed of ultrafine zirconium powder and conventional zirconium powder. The ultrafine zirconium powder has a particle size of 1~5μm, and the conventional zirconium powder has a particle size of 40~100μm. In the composite zirconium powder, ultrafine zirconium powder accounts for 60% of the composite zirconium powder by mass, and the rest is conventional zirconium powder. The purity of the ultrafine zirconium powder is greater than 99%.

[0038] The zirconium hydride has a particle size of 10~100μm.

[0039] The particle size of the aluminum powder is 10~100μm.

[0040] The chemical raw materials required for the propellant are formulated and mixed according to the above formula.

[0041] The mixed raw materials from the above steps are placed into a press and pressed at a pressure of 200 MPa.

[0042] The solid propellant that has been molded and pressed in the above steps is dried to remove moisture and volatile substances, thereby increasing its density and mechanical strength.

[0043] The performance of the propellant was tested. This invention uses thermodynamic software to simulate a water-ramjet engine. This software, based on rigorous thermodynamic principles and equations, comprehensively considers important factors such as the propellant's chemical composition, combustion reaction equations, thermodynamic properties, and combustion products. This invention utilizes this thermodynamic calculation program to perform specific impulse calculations, enabling accurate performance evaluation of the propellant. The relevant propellant parameters are input into the software, with test conditions of a combustion chamber pressure of 68.6 MPa and a nozzle expansion ratio of 70. The optimal water-fuel ratio of the propellant was found to be approximately 1.9. Then, under the condition of a water-fuel ratio of 1.9, the specific impulse and volumetric specific impulse performance of the propellant were simulated. This software can calculate propellant performance parameters under different formulations and operating conditions. The software performs combustion simulation calculations based on various formulas, including the ideal gas law, thermodynamic equations, and enthalpy and entropy calculations.

[0044] Table 1 shows the formulation components and properties of the Zr / ZrH2 / Al / AP metallic fuel propellant obtained in this embodiment.

[0045] Table 1 Formulation components and properties of Zr / ZrH2 / Al / AP metallic fuel propellants

[0046]

[0047] As shown in Table 1, when the propellant is prepared according to the formulation in Table 1, the density of the Zr / ZrH2 / Al / AP metallic fuel propellant is 4.01 g / cm³. 3 Its specific impulse is 4532.9 m / s, and its volumetric specific impulse is 1.81 × 10⁻⁶ m / s. 4 kN·S / m 3 .

[0048] Example 2

[0049] Table 2 shows the formulation components and properties of the Zr / ZrH2 / Al / AP metallic fuel propellant obtained in this embodiment.

[0050] The preparation was carried out in accordance with the method described in Example 1.

[0051] Table 2 Formulation components and properties of Zr / ZrH2 / Al / AP metallic fuel propellants

[0052]

[0053] As shown in Table 2, when the propellant is prepared according to the formulation in Table 2, the density of the Zr / ZrH2 / Al / AP metallic fuel propellant is 4.18 g / cm³. 3 Its specific impulse is 4377.8 m / s, and its volumetric specific impulse is 1.83 × 10⁻⁶ m / s. 4 kN·S / m 3 .

[0054] Example 3

[0055] Table 3 shows the formulation components and properties of the Zr / ZrH2 / Al / AP metallic fuel propellant obtained in this embodiment.

[0056] The preparation was carried out in accordance with the method described in Example 1.

[0057] Table 3 Formulation components and properties of Zr / ZrH2 / Al / AP metallic fuel propellants

[0058]

[0059] As shown in Table 3, when the propellant is prepared according to the formulation in Table 3, the density of the Zr / ZrH2 / Al / AP metallic fuel propellant is 4.33 g / cm³. 3 Its specific impulse is 4198.0 m / s, and its volumetric specific impulse is 1.81 × 10⁻⁶ m / s. 4 kN·S / m 3 .

[0060] Example 4

[0061] Table 4 shows the formulation components and properties of the Zr / ZrH2 / Al / KP metallic fuel propellant obtained in this embodiment.

[0062] The preparation was carried out in accordance with the method described in Example 1.

[0063] Table 4 Formulation components and properties of Zr / ZrH2 / Al / KP metallic fuel propellants

[0064]

[0065] As shown in Table 4, when the propellant is prepared according to the formulation in Table 4, the density of the Zr / ZrH2 / Al / KP metallic fuel propellant is 4.21 g / cm³. 3 Its specific impulse is 4486.6 m / s, and its volumetric specific impulse is 1.89 × 10⁻⁶ m / s. 4 kN·S / m 3 .

[0066] Example 5

[0067] Table 5 shows the formulation components and properties of the Zr / ZrH2 / Al / KP metallic fuel propellant obtained in this embodiment.

[0068] The preparation was carried out in accordance with the method described in Example 1.

[0069] Table 5 Formulation components and properties of Zr / ZrH2 / Al / KP metallic fuel propellants

[0070]

[0071] As shown in Table 5, when the propellant is prepared according to the formulation in Table 5, the density of the Zr / ZrH2 / Al / KP metallic fuel propellant is 4.37 g / cm³. 3 The specific impulse is 4357.0 m / s, and the volumetric specific impulse is 1.90 × 10⁻⁶ m / s. 4 kN·S / m 3 .

[0072] Example 6

[0073] Table 6 shows the formulation components and properties of the Zr / ZrH2 / Al / KP metallic fuel propellant obtained in this embodiment.

[0074] The preparation was carried out in accordance with the method described in Example 1.

[0075] Table 6 Formulation components and properties of Zr / ZrH2 / Al / KP metallic fuel propellants

[0076]

[0077] As shown in Table 6, when the propellant is prepared according to the formula in Table 6, the density of the Zr / ZrH2 / Al / KP metallic fuel propellant is 4.56 g / cm³. 3 Its specific impulse is 4182.7 m / s, and its volumetric specific impulse is 1.91 × 10⁻⁶ m / s. 4 kN·S / m 3 .

[0078] As can be seen from the above embodiments, the present invention greatly improves the density, specific impulse and other properties of the propellant.

[0079] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, and not all embodiments. Other embodiments can be obtained based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A metallic fuel propellant suitable for water-ramming engines, comprising fuel, fuel additives, and an oxidizer, characterized in that, The fuel is zirconium metal powder, the fuel additive is aluminum metal powder and zirconium hydride, and the oxidant is perchlorate; The metallic fuel propellant is composed of the following components in weight percentage: Zirconium metal powder: 50~70%; Zirconium hydride: 8~12%; Aluminum powder: 22.2~30%; Perchlorate: 8~12%; The zirconium metal powder includes ultrafine zirconium powder and conventional zirconium powder; the particle size of the ultrafine zirconium powder is 1~5μm, and the particle size of the conventional zirconium powder is 40~100μm; the mass ratio of ultrafine zirconium powder in the zirconium metal powder is ≤60%.

2. The metallic fuel propellant according to claim 1, characterized in that, The zirconium hydride has a particle size of 10~100μm.

3. The metallic fuel propellant according to claim 1, characterized in that, The particle size of the aluminum powder is 10~100μm.

4. The metallic fuel propellant according to claim 1, characterized in that, The perchlorate includes potassium perchlorate or ammonium perchlorate.

5. The method for preparing the metallic fuel propellant according to any one of claims 1 to 4, characterized in that, Includes the following steps: The fuel, fuel additive, and oxidant are mixed, pressed, and dried in sequence to obtain the metallic fuel propellant.

6. The preparation method according to claim 5, characterized in that, The pressing is performed using a pressing machine, and the pressing pressure is 200 MPa.

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