A high-pressure external pulse generator for solid rocket motors

Abstract

The present invention provides an object of the present invention to provide a high-pressure external pulse generator for a solid rocket engine, comprising an electric gas generator, a gas generator mounting sleeve, a valve core, a valve core spring, a valve core bracket and a base; the components are connected by threads to facilitate assembly and replacement of parts; two metal sealing gaskets play a sealing role, and the ceramic insulation gasket in the middle plays an insulation role. When the engine is working, some high-temperature and high-pressure air will enter the one-way valve, but will not enter the bottom end of the valve core. Even if a small amount enters, the temperature of the valve core spring will not be very high because the one-way valve housing is at room temperature; heat dissipation fins are also added to the outer wall surface of the base and the gas generator mounting sleeve to further enhance the heat dissipation effect.

Description

Technical Field

[0001] The invention belongs to the technical field of unstable combustion of solid rocket engines, and in particular relates to a high-pressure and strong external pulse generator for solid rocket engines. Background Art

[0002] In recent years, solid rocket engines have frequently experienced unstable combustion, which often leads to the extension of the development cycle of solid rocket engines and the best scientific research funds, and even leads to the failure of the development mission. Therefore, it is very urgent to carry out research on unstable combustion of solid rocket engines. Among the causes of unstable combustion, acoustic instability and pressure coupling response gain play a more obvious role, and are also relatively mature in theory. They have always been the focus of scholars' research. Among the many pressure coupling response measurement methods, the T-type burner is the most widely used, and the existing pressure coupling response data are mostly from the measurement results of the T-type burner. The T-type burner is a long cylindrical tube as a whole, and its nozzle throat is located in the middle of the axial length of the burner. This position is the wave node of the first-order standing wave sound field, so the damping effect generated by the nozzle exhaust is the smallest, and the pressure coupling response function value can be measured as accurately as possible. When using the T-type burner for pressure coupling response measurement, for high-aluminum composite propellants, the condensed phase particles in the combustion products have a strong damping effect in the sound field, making it difficult for the T-type burner to produce self-excited acoustic oscillation phenomenon. Therefore, it is necessary to use an external pulse excitation method to generate transient disturbances inside the T-type burner, thereby forming a periodic self-excited oscillation, and then obtain the pressure coupling response function of the propellant based on the pressure oscillation data. The high-pressure external pulse generator of the present invention can be applied to the above research. In the experiment, a pressure pulse of sufficient intensity is generated for the T-type burner to excite periodic pressure oscillations. For the study of acoustic instability, an important data is the acoustic modal frequency of the combustion chamber. In engineering practice, the pulse method is often used for measurement, that is, when the engine is working normally, a pressure pulse is introduced from the head of the combustion chamber, and the acoustic modal frequencies of each order of the combustion chamber are obtained by fast Fourier transformation based on the oscillation attenuation pressure data in the combustion chamber. In the actual engine, the pressure in the combustion chamber during operation is extremely large, generally around 10MPa, and the pressure generated by the pulse generator in a short time is required to exceed the pressure in the combustion chamber by at least 20%. In summary, in the study of unstable combustion of solid rocket engines, an excitation device that can generate high-pressure pulses in the combustion chamber is needed. Summary of the invention

[0003] In view of this, the object of the present invention is to provide a high-pressure external pulse generator for a solid rocket engine, which is easy to install, improves the sealing effect, and reduces high-temperature heat conduction.

[0004] A high-pressure external pulse generator for a solid rocket engine, comprising an electric gas generator (10), a gas generator mounting sleeve (9), a valve core (6), a valve core spring (5), a valve core bracket (4), and a base (11);

[0005] The base (11) is provided with a central through hole, one end of which is installed in the installation hole of the body (1) through a thread, and the other end is provided with a countersunk hole coaxial with the central through hole, and the inner wall of the countersunk hole is processed with an internal thread;

[0006] The base (11) is mounted on one end of the body (1) and is processed into a cylindrical protrusion. The mounting portion of the body (1) that is connected to the base (11) is processed into a stepped countersunk hole that is smaller inside and larger outside. The cylindrical protrusion is screwed into the bottom of the stepped countersunk hole.

[0007] The valve core bracket (4) is axially processed with a central through hole, and the periphery of the central through hole is processed with a vent hole; the valve core bracket (4) is installed at the bottom of the countersunk hole of the base (11);

[0008] One end of the valve core (6) passes through the valve core spring (5) and is inserted into the central through hole of the valve core bracket (4); the other end of the valve core (6) has a protrusion, which clamps the valve core spring (5) on the valve core bracket (4);

[0009] The gas generator mounting sleeve (9) has a central through hole, and both end surfaces are processed with countersunk holes coaxial with the central through hole; the countersunk hole at one end cooperates with the protrusion of the valve core (6) and can be blocked by the valve core (6), and the countersunk hole at the other end is fixed to the ignition end of the gas transmitter (10); one end of the gas generator mounting sleeve (9) on which the valve core (6) is mounted extends into the countersunk hole of the base (11) and is fixed to the base (11) by means of threads.

[0010] Preferably, the two metal sealing gaskets and the ceramic heat-insulating gasket in the middle are sleeved on the cylindrical protrusion of the base (11), and the shoulder of the base (11) presses the two metal sealing gaskets and the ceramic heat-insulating gasket in the outer countersunk hole of the stepped countersunk hole.

[0011] Preferably, one end of the gas generator mounting sleeve (9) docking with the base (11) is provided with two metal sealing gaskets, and a ceramic heat insulating gasket is provided between the two metal sealing gaskets.

[0012] Furthermore, heat dissipation fins are provided on the outer wall surface of the base (11).

[0013] Furthermore, heat dissipation fins are provided on the outer wall surface of the gas generator mounting sleeve (9).

[0014] Preferably, the protrusion of the valve core (6) is conical, and the corresponding countersunk hole of the blocked gas generator mounting sleeve (9) is conical, forming a guide inclined surface sealing method.

[0015] Preferably, the protrusion of the valve core (6) is spherical, and the corresponding countersunk hole of the blocked gas generator mounting sleeve (9) is spherical.

[0016] The present invention has the following beneficial effects:

[0017] The present invention provides a high-pressure external pulse generator for a solid rocket engine, comprising an electric gas generator, a gas generator mounting sleeve, a valve core, a valve core spring, a valve core bracket and a base; the components are connected by threads, which is convenient for assembly and replacement of parts;

[0018] The two metal sealing gaskets play a sealing role, and the ceramic insulation gasket in the middle plays a heat insulation role. When the engine is working, some high-temperature and high-pressure air will enter the one-way valve, but will not enter the bottom of the valve core. Even if a small amount enters, the temperature of the valve core spring will not be very high because the one-way valve housing is at room temperature;

[0019] Heat dissipation fins are also added to the outer wall surface of the base and the gas generator mounting sleeve to further enhance the heat dissipation effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural explosion diagram of the pulse generator of the present invention;

[0021] Figure 2 It is a structural diagram of the pulse generator of the present invention in a closed state;

[0022] Figure 3 It is a structural diagram of the pulse generator of the present invention in an open state;

[0023] Figure 4 It is a schematic diagram of the valve core support structure of the present invention.

[0024] Among them, 1-elastic body, 2, 7-metal sealing gasket, 3, 8-ceramic insulation gasket, 4-valve core bracket, 5-valve core spring, 6-valve core, 9-gas generator installation sleeve, 10-gas generator, 11-base. DETAILED DESCRIPTION

[0025] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0026] like Figure 1 As shown, a high-pressure external pulse generator for a solid rocket engine of the present invention includes an electric gas generator 10, a gas generator mounting sleeve 9, a valve core 6, a valve core spring 5, a valve core bracket 4, metal sealing gaskets 2, 7, ceramic insulation gaskets 3, 8 and a base 11.

[0027] The base 11 is provided with a central through hole, one end of which is installed in the mounting hole of the body 1 through a thread, and the other end is provided with a countersunk hole coaxial with the central through hole, and the inner wall of the countersunk hole is processed with an internal thread;

[0028] The base 11 is installed at one end of the body 1 and processed into a cylindrical protrusion. The installation part of the body 1 that docks with the base 11 is processed into a stepped countersunk hole with a small inside and a large outside. Two metal sealing gaskets 2 and the middle ceramic heat-insulating gasket 3 are sleeved on the cylindrical protrusion of the base 11. The cylindrical protrusion is screwed into the bottom of the stepped countersunk hole. The shoulder of the base 11 presses the two metal sealing gaskets 2 and the middle ceramic heat-insulating gasket 3 into the outer countersunk hole of the stepped countersunk hole. The two metal sealing gaskets 2 play a sealing role, and the middle ceramic heat-insulating gasket 3 plays a heat-insulating role. When the engine is working, some high-temperature and high-pressure air will enter the one-way valve, but will not enter the bottom end of the valve core 6. Even if a small amount enters, the temperature of the valve core spring 5 will not be very high because the one-way valve housing is at room temperature. Due to the addition of the ceramic heat-insulating gasket 2, the gas generator installation sleeve 9 will not have a high temperature for a short time, and it can also absorb part of the heat energy.

[0029] like Figure 4 As shown, the valve core bracket 4 is axially processed with a central through hole, and the periphery of the central through hole is processed with a vent hole; the valve core bracket 4 is installed at the bottom of the countersunk hole of the base 11;

[0030] One end of the valve core 6 passes through the valve core spring 5 and is inserted into the central through hole of the valve core bracket 4. The other end of the valve core 6 has a protrusion, which clamps the valve core spring 5 on the valve core bracket 4.

[0031] The gas generator installation sleeve 9 has a central through hole, and both end faces are processed with countersunk holes coaxial with the central through hole; the countersunk hole at one end cooperates with the protrusion of the valve core 6 and can be blocked by the valve core 6, and the countersunk hole at the other end is fixed to the ignition end of the gas transmitter. One end of the gas generator installation sleeve 9 where the valve core 6 is installed extends into the countersunk hole of the base 11 and is fixed to the base 11 by threads.

[0032] In order to reduce high-temperature heat conduction when the engine is working, two metal sealing gaskets 7 and a ceramic heat-insulating gasket 8 are installed at one end of the gas generator installation sleeve 9 docking the base 11; the three are separated from the main structure of the gas generator installation sleeve 9 docking the base 11, which can extend the heat transfer time. In addition, heat dissipation fins are added to the outer wall surface of the base 11 and the gas generator installation sleeve 9 to further enhance the heat dissipation effect. If the valve core spring 5 has a high temperature during the test, the axial dimension of the base 11 can be lengthened, and heat dissipation fins can be added to reduce the temperature.

[0033] The valve core bracket 4 is made of high temperature resistant nickel-cobalt alloy material, and other structural parts are made of 316 stainless steel material.

[0034] like Figure 2 As shown, the engine is working + the electric gas generator is working:

[0035] When the electric gas generator 10 is powered on (the working time of the gas generator is about 3-5 milliseconds), the gas generated by the electric gas generator 10 pushes the valve core 6 along the central through hole of the gas generator mounting sleeve 9, and the valve core spring 5 is compressed in the elastic body 1. When the electric gas generator 10 is powered on and working, the valve core spring 5 is pressed in the gas valve core bracket 4 and does not contact the high-temperature gas.

[0036] like Figure 3 As shown, the engine working + electric gas generator working end state:

[0037] When the pressure in the body 1 is equal to or higher than the pressure in the one-way valve, the valve core 6 moves in the opposite direction under the action of the valve core spring 5 and the gas pressure of the body 1, and blocks the gas generator mounting sleeve 9 to close the one-way valve. The higher the pressure, the faster the closing speed.

[0038] In order to improve the sealing performance, the protrusion of the valve core 6 is designed to be conical, and the corresponding countersunk hole of the blocked gas generator mounting sleeve 9 is also designed to be conical, forming a guide inclined surface sealing method; or both are designed to be spherical shapes that match each other, which can also improve the sealing performance.

[0039] Since there is air in the valve body, no residues from the engine will enter the valve core 6 on the sealing surface of the valve core 6 .

[0040] The pulse generator of the present invention can inject high-temperature and high-pressure combustion gas into the T-type burner in an experiment of measuring the propellant pressure coupling response function by the pulse method, thereby stimulating the propellant combustion process in the T-type burner and generating an unstable combustion phenomenon. Finally, the pressure coupling response function of the propellant is measured, and a pulse pressure can be generated in an acoustic frequency measurement experiment in the combustion chamber of a solid rocket engine, and the pulse duration is about 0.1s.

[0041] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A high-pressure external pulse generator for a solid rocket engine, characterized in that: It comprises an electric gas generator (10), a gas generator mounting sleeve (9), a valve core (6), a valve core spring (5), a valve core bracket (4) and a base (11); The base (11) is provided with a central through hole, one end of which is installed in the installation hole of the body (1) through a thread, and the other end is provided with a countersunk hole coaxial with the central through hole, and the inner wall of the countersunk hole is processed with an internal thread; The base (11) is installed on one end of the body (1) and is processed into a cylindrical protrusion. The installation part of the body (1) that is connected to the base (11) is processed into a stepped countersunk hole that is small inside and large outside. The cylindrical protrusion is screwed into the bottom of the stepped countersunk hole. The valve core bracket (4) is axially processed with a central through hole, and the periphery of the central through hole is processed with a vent hole; the valve core bracket (4) is installed at the bottom of the countersunk hole of the base (11); One end of the valve core (6) passes through the valve core spring (5) and is inserted into the central through hole of the valve core bracket (4); the other end of the valve core (6) has a protrusion, which clamps the valve core spring (5) on the valve core bracket (4); The gas generator installation sleeve (9) has a central through hole, and both end surfaces are processed with countersunk holes coaxial with the central through hole; the countersunk hole at one end cooperates with the protrusion of the valve core (6) and can be blocked by the valve core (6), and the countersunk hole at the other end is fixed to the ignition end of the gas transmitter (10); one end of the gas generator installation sleeve (9) on which the valve core (6) is installed extends into the countersunk hole of the base (11) and is fixed to the base (11) by means of threads.

2. A high-pressure external pulse generator for a solid rocket motor as claimed in claim 1, characterized in that: The two metal sealing gaskets and the ceramic heat-insulating gasket in the middle are sleeved on the cylindrical protrusion of the base (11), and the shoulder of the base (11) presses the two metal sealing gaskets and the ceramic heat-insulating gasket in the outer countersunk hole of the stepped countersunk hole.

3. A high-pressure external pulse generator for a solid rocket engine as claimed in claim 1, characterized in that: Two metal sealing gaskets are sleeved on one end of the gas generator installation sleeve (9) docking with the base (11), and a ceramic heat insulation gasket is arranged between the two metal sealing gaskets.

4. A high-pressure external pulse generator for a solid rocket engine as claimed in claim 2 or 3, characterized in that: Heat dissipation fins are arranged on the outer wall surface of the base (11).

5. A high-pressure external pulse generator for a solid rocket engine as claimed in claim 2 or 3, characterized in that: Heat dissipation fins are arranged on the outer wall surface of the gas generator installation sleeve (9).

6. A high-pressure external pulse generator for a solid rocket engine as claimed in claim 2 or 3, characterized in that: The protrusion of the valve core (6) is conical, and the corresponding countersunk hole of the blocked gas generator installation sleeve (9) is conical, forming a guide inclined surface sealing method.

7. A high-pressure external pulse generator for a solid rocket engine as claimed in claim 2 or 3, characterized in that: The protrusion of the valve core (6) is spherical, and the corresponding countersunk hole of the blocked gas generator installation sleeve (9) is spherical.

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