A spherical shaped charge nozzle

Abstract

This invention discloses a spherical shaped charge nozzle, comprising a nozzle outer wall, a nozzle propagation section, a nozzle contraction section, a nozzle converging cavity, a nozzle throat, and a nozzle expansion section. The front end of the nozzle propagation section is connected to the rear end of the combustion chamber of a detonation engine. The rear end of the nozzle propagation section is provided with the nozzle contraction section, forming a bend. The nozzle converging cavity has a spherical structure, and the bend is evenly distributed on the outer wall surface of the nozzle converging cavity. The nozzle adopts a structure with a uniformly decreasing inner diameter from the inlet of the nozzle propagation section to the outlet of the nozzle contraction section, and the axis at the outlet of the nozzle contraction section passes through the center of the nozzle converging cavity. The nozzle throat and the nozzle expansion section are coaxially arranged sequentially at the rear end of the nozzle converging cavity. This nozzle has a simple structure, simple assembly process, high safety and reliability, and good engineering applicability and interchangeability.

Description

Technical Field

[0001] This invention belongs to the field of detonation engine technology and mainly relates to a spherical shaped charge nozzle. Background Technology

[0002] Currently, traditional pulse detonation engines operate at low frequencies and have low combustion chamber pressures. The boost ratio from a single detonation is limited, and the thrust is discontinuous. Increasing the engine's operating frequency and combustion chamber filling pressure can further improve engine performance. However, detonation engines are constrained by size; the larger the diameter, the more difficult it is to initiate detonation, limiting the operating frequency and resulting in discontinuous thrust. Using high-pressure filling detonation can lead to fuel overfilling, where fresh fuel is discharged from the detonation tube with the exhaust gas before participating in the combustion reaction, resulting in decreased combustion efficiency and a drop in engine specific impulse. Summary of the Invention

[0003] The purpose of this invention is to provide a spherical shaped charge nozzle that solves the problems of low operating frequency of detonation engines and overfilling under high pressure in existing technologies.

[0004] To achieve the above objectives, the present invention employs the following technical solution: A spherical shaped charge nozzle includes a nozzle outer wall, a nozzle propagation section, a nozzle contraction section, a nozzle converging cavity, a nozzle throat, and a nozzle expansion section, wherein: The front end of the nozzle propagation section is connected to the rear end of the combustion chamber of the detonation engine. The rear end of the nozzle propagation section is provided with a nozzle contraction section, and the two together form a bend. The nozzle converging cavity is a spherical structure, and the bend is evenly arranged on the outer wall of the nozzle converging cavity. From the inlet of the nozzle propagation section to the outlet of the nozzle contraction section, the inner diameter is uniformly reduced. The axis at the outlet of the nozzle contraction section passes through the center of the sphere of the nozzle converging cavity. The nozzle throat and the nozzle expansion section are arranged coaxially at the rear end of the nozzle converging cavity. After the detonation engine ignites, the generated detonation wave and overfilled fuel flow propagate through the nozzle propagation section and nozzle contraction section with variable cross-section, forming a primary compression zone. When the detonation wave diffuses through the nozzle contraction section outlet towards the nozzle converging cavity, the surrounding constraints change abruptly, and the shock wave and reaction surface of the detonation wave gradually decouple from the periphery of the wave surface towards the center, degenerating into a leading shock wave and a reaction surface. After the simultaneous ignition of the detonation engines in the same group, the leading shock wave and combustion products generate a high-speed radial flow that is axisymmetric around the axis of the nozzle converging cavity. The high-speed radial flow propagates towards the center of the converging cavity and collides at the center point of the nozzle converging cavity, generating local high temperature and high pressure, thus forming a secondary compression zone. This zone compresses the combustion products and overfilled fuel and triggers secondary detonation combustion. The combustion products generated by the secondary detonation in the secondary compression zone are propelled by the detonation wave and shock wave reflected from the front end of the nozzle converging cavity to form a hypersonic jet. This jet is ejected towards the nozzle throat at the rear end of the nozzle converging cavity in a controlled impact direction.

[0005] Furthermore, the axis of the nozzle propagation section is parallel to the axis of the nozzle converging cavity; the inner diameter change rate of both the nozzle propagation section and the nozzle contraction section is 0.5~0.8, and the angle between the axis of the nozzle contraction section outlet and the axis of the nozzle converging cavity is 30°~90°.

[0006] Furthermore, the number of nozzle propagation sections is designed to be 2N, where N is a positive integer; two sets of nozzle propagation sections symmetrical to the axis of the nozzle converging cavity form a group, the combustion chambers corresponding to the same set of nozzle propagation sections are synchronously ignited, and the combustion chambers of different groups are asynchronously pulsed ignited.

[0007] Furthermore, the spherical radius of the nozzle converging cavity The diameter of the nozzle converging section exit Calculation yielded:

[0008] in, The preset nozzle expansion ratio, This refers to the outlet diameter of the nozzle's converging section.

[0009] Furthermore, the nozzle converging chamber is made of high-temperature alloy material, and the outer wall thickness of the nozzle converging chamber is... :

[0010] in, This is the pressure fluctuation coefficient. The radius of the nozzle converging cavity sphere; This is the welding strength attenuation coefficient. The working pressure of the secondary compression zone; This represents the allowable stress of the material.

[0011] Furthermore, the nozzle throat is a Laval nozzle contraction section configuration, and the nozzle expansion section is a Laval nozzle expansion section configuration.

[0012] Furthermore, the expansion angle of the nozzle expansion section is 10°~18°, and the length of the nozzle expansion section... throat diameter of the nozzle throat The ratio is 8 to 9.5.

[0013] Furthermore, the exit diameter of the nozzle expansion section Calculated using the following formula:

[0014] in This refers to the exit cross-sectional area of ​​the nozzle expansion section. This is the exit cross-sectional area of ​​the nozzle throat. This refers to the diameter of the throat of the nozzle.

[0015] A detonation engine employing the aforementioned spherical shaped charge nozzle.

[0016] Compared with the prior art, the present invention has the following technical features: This invention employs synchronous ignition of the same set of detonation tubes and asynchronous ignition of each set of detonation tubes to increase the engine's operating frequency and generate continuous thrust. In the concave region of the nozzle converging chamber, detonation waves collide, converge, and repeatedly superimpose, forming a high-temperature, high-pressure region. This compresses unreacted fuel and triggers secondary detonation combustion, improving fuel utilization and increasing the engine's specific impulse. The spherical shaped charge nozzle of this invention features concentrated energy, strong directionality, and a fast exhaust jet, accelerating the discharge of combustion gases, improving engine combustion efficiency, and further enhancing the engine's propulsive performance. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the spherical energy-concentrating nozzle structure of the present invention; Figure 2 This is a schematic diagram of a spherical shaped charge nozzle prototype; Figure 3 This is a side view of a spherical shaped charge nozzle; Figure 4 This is a front view of a spherical shaped charge nozzle. Figure 5 This is a simulation calculation cloud map of a spherical shaped charge nozzle.

[0018] Explanation of reference numerals in the attached drawings: 1. Outer wall of nozzle; 2. Propagation section of nozzle; 3. Contraction section of nozzle; 4. Converging chamber of nozzle; 5. Throat of nozzle; 6. Expansion section of nozzle; 7. Flange; 8. Combustion chamber. Detailed Implementation

[0019] This invention provides a spherical shaped charge nozzle that incorporates the concepts of energy convergence and secondary detonation into the design of a detonation engine, thereby improving the engine's operating frequency and performance. The operating frequency is increased by synchronous ignition of the same set of detonation tubes and asynchronous ignition of the other sets. The spherical shaped charge nozzle's throat pressure build-up and the superposition and convergence of detonation waves trigger secondary detonation combustion in overfilled fuel. Furthermore, the concentrated energy, strong directionality, and rapid exhaust jet of the spherical shaped charge nozzle further enhance the engine's propulsive performance. This nozzle is suitable for rocket-type pulse detonation engines and combined ramjet pulse detonation engines.

[0020] The present invention provides a spherical shaped charge nozzle, comprising a nozzle outer wall 1, a nozzle propagation section 2, a nozzle contraction section 3, a nozzle converging cavity 4, a nozzle throat 5, and a nozzle expansion section 6, wherein: The front end of the nozzle propagation section 2 is connected to the rear end of the combustion chamber 8 of the detonation engine. The rear end of the nozzle propagation section 2 is provided with a nozzle contraction section 3, which together form a bent section. The nozzle converging cavity 4 has a spherical structure, and the bent section is evenly distributed on the outer wall surface of the nozzle converging cavity 4. The inner diameter of the nozzle propagation section 2 is uniformly reduced from the inlet to the outlet of the nozzle contraction section 3. The axis at the outlet of the nozzle contraction section 3 passes through the center of the sphere of the nozzle converging cavity 4. The nozzle throat 5 and the nozzle expansion section 6 are arranged coaxially at the rear end of the nozzle converging cavity 4. In a preferred embodiment of the present invention, after the detonation engine is ignited, the generated detonation wave, combustion products, and overfilled fuel propagate through the nozzle propagation section 2 and the nozzle contraction section 3 via a variable cross-section, forming a primary compression zone. When the detonation wave diffuses through the nozzle contraction section 3 towards the nozzle converging cavity 4, the surrounding (wall) constraint conditions abruptly change. The shock wave and reaction surface of the detonation wave gradually decouple from the periphery of the wave surface towards the center, degenerating into a leading shock wave and a reaction surface. The leading shock wave and combustion products form a high-speed radial flow toward the center of the nozzle converging cavity 4. After synchronous ignition of the same group of detonation engines, a high-speed radial flow symmetrical about axis A of the nozzle converging cavity 4 is generated. The high-speed radial flow propagates toward the center of the converging cavity 4 and collides at the center point of the nozzle converging cavity 4, generating local high temperature and high pressure, with a pressure value of [insert pressure value here]. This creates a secondary compression zone, which compresses the combustion products and incompletely reacted fuel mixture and triggers secondary detonation combustion, allowing the fuel molecules to fully release energy and further increasing the pressure and temperature of the nozzle converging chamber 4, thus increasing the kinetic energy of the shock wave. The combustion products generated by the secondary detonation in the secondary compression zone are driven by the detonation wave and shock wave reflected from the front end of the nozzle converging chamber 4 to form a hypersonic jet. This jet is ejected towards the nozzle throat 5 at the rear end of the nozzle converging chamber 4 in a controlled impact direction.

[0021] The rear end of the combustion chamber of the detonation engine 8 is connected to the nozzle propagation section 2 via a flange 7. Traditional pulse detonation engines have low pressure, limited pressure ratio for a single detonation, and are constrained by size specifications, limiting their operating frequency. To further increase the operating frequency of the detonation engine, a combustion chamber 8 with a diameter of 20-40 mm is preferred as the input device for the spherical shaped charge nozzle. The detonation engine uses inexpensive conventional fuels, such as gasoline, kerosene, acetylene, butane, propane, natural gas, and a mixture of air or oxidizer to form a mixed fuel. This mixed fuel is ignited in the combustion chamber 8 of the detonation engine at a suitable equivalence ratio, initiating detonation. Under effective positive pressure, the combustion products and unreacted mixed fuel are injected into the nozzle propagation section 2.

[0022] The front end of nozzle propagation section 2 is connected to the rear end of combustion chamber 8 of the detonation engine via flange 7. The cross-sectional area of ​​the rear outlet of combustion chamber 8 is the same as the cross-sectional area of ​​the front inlet of nozzle propagation section 2. The rear end of nozzle propagation section 2 is connected to the front end of nozzle contraction section 3. During the ignition process of the detonation engine, a detonation wave is generated. The detonation wave rapidly sweeps across the mixed fuel, accelerating the chemical reaction of the mixed fuel and forming combustion products. The combustion products and unreacted mixed fuel are propelled towards the rear end of the combustion chamber by the detonation wave and flow into nozzle propagation section 2. Nozzle propagation section 2 is generally of a contraction configuration, with its inner diameter gradually decreasing from the front end to the rear end. Its length is 80mm~120mm, and the rate of change of inner diameter is 0.5~0.8. For incompressible fluids, when flowing steadily in a pipe, the mass of fluid passing through any cross-sectional area of ​​the pipe per unit time is equal, i.e. , Volumetric flow rate, For flow rate, The cross-sectional area of ​​the pipe is denoted as 2. As the internal cross-sectional area of ​​the nozzle propagation section 2 gradually decreases, the propagation speed of the combustion products flowing out from the rear end of the combustion chamber 8 of the detonation engine in the nozzle propagation section 2 gradually increases. The rapid increase in flow velocity generates a significant pressure difference, and the pressure inside the nozzle propagation section 2 gradually increases.

[0023] In a preferred embodiment of the present invention, the front end of the nozzle converging section 3 is connected to the nozzle propagation section 2, and the rear end is connected to the nozzle converging cavity 4. The nozzle converging section 3 and the nozzle propagation section 2 are integrally cast, with an internal converging configuration, and the overall structure is a bent section. The inner diameter of the nozzle converging section 3 gradually decreases from the front end to the rear end. In this embodiment, the turning radius is 60mm, and a uniform variable diameter configuration is adopted, with an inner diameter change rate of 0.5~0.8, which must be consistent with the inner diameter change rate of the nozzle propagation section 2, i.e., the outlet diameter of the nozzle converging section 3. The inlet diameter of nozzle propagation section 2 0.5 to 0.8 times, When the inner diameter change rate is 0.5~0.8, the combustion products flowing inside can smoothly transition from the large diameter to the small diameter, enabling a rapid increase in flow velocity to generate a significant pressure difference. This establishes a higher pressure at the throat of the nozzle propagation section 2, forming a primary compression zone with a pressure value of [value missing]. At the same time, it can avoid excessive contraction angle inside the nozzle contraction section 3, which would cause combustion products to flow and separate from the pipe wall, resulting in vortices and turbulence.

[0024] The bends formed by the nozzle propagation section 2 and the nozzle contraction section 3 are circumferentially distributed on the outer wall of the nozzle converging cavity 4. The axis of the nozzle propagation section 2 is parallel to the axis A of the coaxially arranged nozzle converging cavity 4, nozzle throat 5, and nozzle expansion section 6. To ensure that the detonation wave collides with each other at the center point of the sphere within the nozzle converging cavity 4, and forms multiple collisions and reflections at the front sphere of the nozzle converging cavity 4, the extended axis of the nozzle contraction section 3 outlet (throat position) must pass through the center of the sphere of the nozzle converging cavity 4. The angle between the axis of the nozzle contraction section 3 outlet and the axis A of the nozzle converging cavity 4 is designed to be 30° to 90°, and the number of nozzle propagation sections 2 is designed to be 2N (N=1 / 2 / 3). The two sets of nozzle propagation sections 2 symmetrical to the axis A of the nozzle converging cavity 4 are... A set of combustors; to ensure that the combustion chambers 8 of the detonation engines connected to each nozzle propagation section 2 generate detonation waves of the same frequency, the combustion chambers 8 of the detonation engines corresponding to the same set of nozzle propagation sections 2 (i.e., the same set of combustion chambers) need to be ignited synchronously; to increase the collision frequency of the detonation waves and the number of secondary detonations in the nozzle converging cavity 4, thereby increasing the exhaust efficiency and thrust performance of the spherical energy-conforming nozzle, the combustion chambers 8 of different sets can adopt asynchronous pulse ignition. This method can adjust the flow rate of combustion products and mixed fuel by means of the propagation speed of the detonation waves, accelerate the outflow of combustion products and the inflow of mixed fuel, and form a rapid cyclic detonation; the ignition time interval is the duration from which the combustion chambers of a set of detonation engines complete ignition, form detonation, and discharge combustion products.

[0025] In a preferred embodiment of the present invention, the outer wall of the nozzle converging cavity 4 is connected to the nozzle contraction section 3, and the nozzle throat 5 is coaxially disposed at the rear end of the nozzle converging cavity 4; the nozzle converging cavity 4 adopts a spherical configuration, and its spherical radius is... It can be obtained from the nozzle converging section outlet with a diameter of 3 Calculations show that, due to the sudden expansion configuration formed by the nozzle converging chamber 4 and the nozzle contraction section 3 outlet, the detonation wave and combustion products are subjected to the working pressure of the primary compression zone when passing through the nozzle contraction section 3 outlet. Driven by the detonation wave, the momentum of the combustion products increases, and they are injected from the nozzle contraction section 3 into the nozzle converging chamber 4. When the detonation wave and combustion products are injected into the nozzle converging chamber 4, the surrounding (wall) constraint conditions change abruptly, similar to a Laval nozzle, and the preferred nozzle expansion ratio is obtained. When the expansion ratio is 7-10, under-expansion or over-expansion can be avoided, preventing blockage. The spherical radius of the nozzle converging cavity 4 can be obtained using the following expansion ratio formula. :

[0026] in The radius of the nozzle converging cavity is 4 spheres. The nozzle converging section 3 has an outlet diameter; there exists at least a spherical radius between the center of the nozzle converging chamber 4 and the nozzle throat 5. The distance.

[0027] In a preferred embodiment of the present invention, the working pressure at the center of the nozzle converging cavity 4 is high, the gas flow is complex, and there are numerous shock wave collisions and reflections. Therefore, the nozzle converging cavity 4 needs to be made of a material with high strength, good toughness, good rigidity, and good processability and economy. Considering the above factors, in one embodiment of the present invention, the nozzle converging cavity 4 is designed to be made of a high-temperature alloy material and integrally formed using a 3D printing process, resulting in a material with high strength. Therefore, based on the material strength of the high-temperature alloy, the outer wall thickness of the nozzle converging cavity 4 can be calculated. :

[0028] in This is the pressure fluctuation coefficient, usually taken as 1.1; The radius of the nozzle converging cavity is 4 spheres; This is the welding strength attenuation coefficient, usually taken as 0.99; The working pressure of the secondary compression zone; This represents the allowable stress of the material.

[0029] In a preferred embodiment of the present invention, the front end of the nozzle throat 5 is connected to the nozzle converging cavity 4, and the rear end is connected to the nozzle expansion section 6. This component is a Laval nozzle contraction section configuration. To ensure that the high-speed jet formed at the center of the nozzle converging cavity 4 can smoothly pass through the nozzle throat 5 and be discharged, the throat diameter of the nozzle throat 5 is... The nozzle should have a converging section 3 outlet diameter. Slightly larger .

[0030] In a preferred embodiment of the present invention, the front end of the nozzle expansion section 6 is connected to the nozzle throat 5, and the overall configuration is a Laval nozzle expansion section configuration. To balance the acceleration of the high-speed jet formed by combustion products and reduce energy loss, the expansion angle of the nozzle expansion section 6 is preferably 10°~18°; to ensure that the high-speed jet expands sufficiently and maintains stable efficiency after passing through the Laval nozzle, the length of the nozzle expansion section 6 is... The throat diameter of nozzle throat 5 The ratio is designed to be 8~9.5, therefore, the length of the nozzle expansion section 6 can be obtained based on the optimal length-radial ratio. , ,in The diameter of the throat 5 of the nozzle throat.

[0031] To optimize the pressure matching of the high-speed jet, avoid under-expansion or over-expansion, and further improve thrust efficiency, the nozzle expansion ratio is optimized. Therefore, the exit diameter of nozzle expansion section 6 It can be obtained based on the optimal expansion ratio. ,in The nozzle expansion section 6 has an exit cross-sectional area. Let 5 be the exit cross-sectional area of ​​the nozzle throat. The diameter of the throat 5 of the nozzle throat.

[0032] Compared with conventional Laval nozzles, spherical shaped charge nozzles have the advantages of concentrated energy, strong directionality, and high exhaust jet velocity, which can further improve the engine's performance.

[0033] In a preferred embodiment of the present invention, two symmetrical combustion chambers 8 are grouped together and synchronous ignition is adopted. The two groups of combustion chambers 8 adopt asynchronous ignition. The detonation wave and overfilled fuel propagate through the nozzle propagation section 2 to the nozzle contraction section 3 with variable cross-section. Under the pressure build-up at the outlet of the nozzle contraction section 3, the overfilled fuel accumulates in the nozzle converging cavity 4. When the detonation wave passes through the outlet of the nozzle contraction section 3, the surrounding (wall) constraint conditions change abruptly. The shock wave and the reaction surface of the detonation wave gradually decouple from the periphery of the wave surface to the center, degenerating into a leading shock wave and a reaction surface. Multiple leading shock waves collide, converge, and repeatedly superimpose in the concave area at the front end of the nozzle converging cavity 4, generating a local high temperature and high pressure zone. This compresses the overfilled fuel that has not participated in the reaction and triggers secondary detonation combustion, allowing the fuel molecules to fully release energy and increasing the pressure and temperature of the nozzle converging cavity 4. Subsequently, the detonation combustion generates a large amount of high temperature and high pressure gas, which is discharged along the axis A of the nozzle expansion section 6, generating thrust. Compared with conventional Laval nozzles, spherical shaped charge nozzles have the advantages of concentrated energy, strong directionality, and high exhaust jet velocity, which can further improve the engine's performance. The nozzle has a simple structure, simple assembly process, high safety and reliability, and good engineering applicability and interchangeability.

[0034] Example: Based on the design conditions, the internal flow field of the spherical shaped charge nozzle was simulated and calculated to obtain the working conditions of the spherical shaped charge nozzle and the reaction process of the nozzle converging cavity 4 during one working cycle. Specific calculation results are as follows: Figure 5 As shown, the calculated working pressure P0 at the inlet of nozzle propagation section 2 is 28 MPa, and the working pressure at the outlet of the throat of nozzle compression section 3 is... The pressure in nozzle converging chamber 4 after the impact, reflection, and secondary compression detonation of the detonation wave is 50 MPa. It rapidly increases to 100 MPa, then expands and accelerates through the nozzle before being discharged, generating thrust.

[0035] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A spherical shaped charge nozzle, characterized in that, It includes the nozzle outer wall (1), the nozzle propagation section (2), the nozzle contraction section (3), the nozzle converging chamber (4), the nozzle throat (5), and the nozzle expansion section (6), wherein: The front end of the nozzle propagation section (2) is connected to the rear end of the combustion chamber (8) of the detonation engine. The rear end of the nozzle propagation section (2) is provided with a nozzle contraction section (3), which together form a bent section. The nozzle converging cavity (4) is a spherical structure, and the bent section is evenly arranged on the outer wall surface of the nozzle converging cavity (4). From the inlet of the nozzle propagation section (2) to the outlet of the nozzle contraction section (3), the inner diameter is uniformly reduced. The axis at the outlet of the nozzle contraction section (3) passes through the center of the sphere of the nozzle converging cavity (4). The nozzle throat (5) and the nozzle expansion section (6) are arranged coaxially at the rear end of the nozzle converging cavity (4). After the detonation engine is ignited, the generated detonation wave and overfilled fuel flow propagate through the nozzle propagation section (2) and nozzle contraction section (3) with a variable cross-section, forming a primary compression zone. When the detonation wave diffuses from the nozzle contraction section (3) outlet to the nozzle converging cavity (4), the surrounding constraint conditions change abruptly, and the shock wave and reaction surface of the detonation wave gradually decouple from the periphery of the wave surface to the center, degenerating into a leading shock wave and a reaction surface. After the detonation engines in the same group are ignited synchronously, the leading shock wave and combustion products generate an axisymmetric shock wave around the axis of the nozzle converging cavity (4). The high-speed radial flow propagates towards the center of the converging cavity (4) and collides at the center point of the nozzle converging cavity (4), generating local high temperature and high pressure, thereby forming a secondary compression zone, which compresses the combustion products and overfilled fuel and triggers secondary detonation combustion; the combustion products generated by the secondary detonation in the secondary compression zone are driven by the detonation wave and shock wave reflected from the front end of the nozzle converging cavity (4) to form a hypersonic jet, which is ejected towards the nozzle throat (5) at the rear end of the nozzle converging cavity (4) in a controlled impact direction.

2. The spherical shaped charge nozzle according to claim 1, characterized in that, The axis of the nozzle propagation section (2) is parallel to the axis of the nozzle converging cavity (4); the inner diameter change rate of the nozzle propagation section (2) and the nozzle contraction section (3) is 0.5~0.8, and the angle between the axis of the nozzle contraction section 3 outlet and the axis of the nozzle converging cavity (4) is 30°~90°.

3. The spherical shaped charge nozzle according to claim 1, characterized in that, The number of nozzle propagation sections (2) is designed to be 2N, where N is a positive integer; two sets of nozzle propagation sections (2) symmetrical to the axis of the nozzle converging cavity (4) are a group, and the combustion chambers (8) corresponding to the same set of nozzle propagation sections (2) are synchronously ignited, while the combustion chambers (8) of different groups are asynchronously pulsed ignited.

4. The spherical shaped charge nozzle according to claim 1, characterized in that, The spherical radius of the nozzle converging cavity (4) The nozzle converging section (3) outlet diameter Calculation yielded: in, The preset nozzle expansion ratio, The outlet diameter of the nozzle converging section (3) is given.

5. The spherical shaped charge nozzle according to claim 1, characterized in that, The nozzle converging chamber (4) is made of high-temperature alloy material, and the outer wall thickness of the nozzle converging chamber (4) is... : in, This is the pressure fluctuation coefficient. The radius of the sphere in the nozzle converging cavity (4); This is the welding strength attenuation coefficient. The working pressure of the secondary compression zone; This represents the allowable stress of the material.

6. The spherical shaped charge nozzle according to claim 1, characterized in that, The nozzle throat (5) is a Laval nozzle contraction section configuration, and the nozzle expansion section (6) is a Laval nozzle expansion section configuration.

7. The spherical shaped charge nozzle according to claim 1, characterized in that, The expansion angle of the nozzle expansion section (6) is 10°~18°, and the length of the nozzle expansion section (6) is... The throat diameter of the nozzle throat (5) The ratio is 8 to 9.

5.

8. The spherical shaped charge nozzle according to claim 1, characterized in that, Exit diameter of nozzle expansion section (6) Calculated using the following formula: in The exit cross-sectional area of ​​the nozzle expansion section (6) is... Let be the exit cross-sectional area of ​​the nozzle throat (5). The diameter of the throat of the nozzle (5) is denoted as .

9. A knock engine, characterized in that, The engine employs a spherical shaped charge nozzle as described in any one of claims 1-8.

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