Superstructure for damping and shock-resisting functions of linear separation device

Abstract

The invention discloses a superstructure for shock absorption and impact resistance functions of a linear separation device. The superstructure comprises an impact reduction structure unit and an external frame, wherein the outer frame is of a cuboid structure, a hollow cavity is formed in the outer frame, the impact reduction structure unit is of a phonon crystal structure and is composed of two local resonance units which are transversely arranged in the hollow cavity side by side, and the center position of each local resonance unit is provided with one center position mass block; the upper end and the lower end of the central position mass block are connected with the upper side and the lower side of the external frame through two spiral connecting rods respectively to form a central resonant cavity. The impact reduction structure unit forms double band gaps through local resonance so as to reduce explosion separation impact. When the device is applied to an aircraft, explosion separation local resonance impact reduction can be achieved, meanwhile, scattering and attenuation of stress waves can be achieved, and the purpose of reducing the explosion separation impact environment is achieved.

Description

Technical Field

[0001] The invention relates to the field of aerospace shock reduction structures, in particular to a super structure for shock reduction and shock resistance functions of a linear separation device. Background Art

[0002] During the explosive separation of a spacecraft, the strong shock wave and preload release generated by the explosion will cause the structure of the spacecraft to produce a local instantaneous high-frequency, high-amplitude shock response, thereby creating a harsh shock environment. This type of shock environment usually does not damage the main structure of the spacecraft, but it is easy to cause failure or damage to many precision equipment or components inside, which has a fatal impact on the launch mission.

[0003] Phononic crystals are materials or structures prepared by arranging materials with different elastic moduli in a certain periodicity, and have band gap characteristics. In view of the explosive separation shock environment faced by aerospace vehicles, a superstructure with local resonance shock reduction is designed based on the local resonance band gap, which can greatly reduce the severity of the shock environment within a specific frequency range, which is of great significance for ensuring the smooth completion of the launch mission. Summary of the invention

[0004] The technical problem solved by the present invention is: to overcome the shortcomings of the prior art and provide a superstructure for the shock absorption and impact resistance of a linear separation device, so as to solve the problem that the strong shock wave generated by the explosion during the explosive separation of a spacecraft causes the structure of the spacecraft to produce a local instantaneous high-frequency, high-amplitude impact response or even damage, and can achieve local resonance shock reduction during the explosive separation, and at the same time can achieve scattering and attenuation of stress waves, so as to achieve the purpose of reducing the explosive separation shock environment.

[0005] The technical solution of the present invention is: to provide a superstructure for the shock absorption and impact resistance function of a linear separation device, comprising: an impact reduction structural unit and an external frame; the external frame is a rectangular structure with a hollow cavity therein, the impact reduction structural unit adopts a phononic crystal structure, and is composed of two local resonance units, which are arranged laterally in parallel in the hollow cavity, and the center position of each local resonance unit is a center position mass block, and the upper and lower ends of the center position mass block are respectively connected to the upper and lower sides of the external frame through two spiral connecting rods to form a central resonant cavity; the impact reduction structural unit forms a double band gap through local resonance to reduce the explosion separation shock.

[0006] Furthermore, the upper end of the center position mass block is connected to the first spiral connecting rod, and the lower end is connected to the second spiral connecting rod; the first spiral connecting rod surrounds the center position mass block once and is connected to the upper side of the external frame, the second spiral connecting rod surrounds the center position mass block once and is connected to the lower side of the external frame, and the first spiral connecting rod and the second spiral connecting rod are staggered and surrounded.

[0007] Furthermore, the center position mass block is a cylinder.

[0008] Furthermore, the superstructure is arranged in an array from top to bottom along the longitudinal direction and penetrated in the transverse direction to match the length of the linear separation device. Grooves are set on the upper and lower sides and connected to the linear separation device structure of the aircraft through the grooves, and is applied to the explosion separation of the aircraft.

[0009] Furthermore, the cross-sectional dimensions of the external frame are 24.4×11.4 mm, the mass block at the center is a cylinder with a diameter of 5 to 6 mm, and the thickness of the spiral connecting rod is 0.3 to 0.5 mm.

[0010] Furthermore, the cross-sectional dimensions of the external frame are 24.4×11.4 mm, the mass block at the center is a cylinder with a diameter of 5.2 mm, and the thickness of the spiral connecting rod is 0.4 mm.

[0011] Furthermore, the material of the superstructure is AlSi10Mg aluminum alloy.

[0012] Furthermore, the first band gap of the shock-reducing structural unit is located between the fourth and fifth energy bands, ie, 1125 Hz-1172 Hz, and the second band gap is located between the sixth and seventh order energy band curves, ie, 1270 Hz-1354 Hz.

[0013] Furthermore, the wall thickness on both sides of the short side direction of the external frame is greater than the thickness at the fracture position of the linear separation device structure.

[0014] Furthermore, the wall thickness of both sides of the outer frame in the short side direction is 2 to 3 mm.

[0015] The advantages of the present invention compared with the prior art are:

[0016] (1) The present invention discloses a superstructure for the shock absorption and impact resistance of a linear separation device, namely a phononic crystal, which realizes the local resonance shock reduction of explosion separation and can also realize the scattering and attenuation of stress waves to achieve the purpose of reducing the shock environment of explosion separation, thereby solving the problem that the strong shock wave generated by the explosion during the explosion separation of a spacecraft causes the structure of the spacecraft to produce a local instantaneous high-frequency, high-amplitude shock response or even damage.

[0017] (2) Phononic crystals usually require both hard and soft phase materials during the design process. However, in the actual design process of the aerospace industry, the overall structure of the aircraft needs to take into account factors such as high load-bearing capacity, high temperature resistance and light weight. Therefore, in a superstructure for the shock absorption and impact resistance of a linear separation device disclosed in the present invention, a spiral connection structure is used to replace the soft materials such as rubber used in conventional research, while taking into account various performances of the structure.

[0018] (3) The structural material of the present invention is AlSi10Mg aluminum alloy, the energy band curve is between the fourth and fifth order, and the sixth and seventh order energy band curves, with double band gaps, and the absolute band gap widths are 47Hz and 84Hz respectively. This structure not only increases the band gap width, but also has a good suppression effect on explosion shock elastic waves within the frequency range.

[0019] (4) The present invention has the advantages of strong bearing capacity, simple structure, easy preparation, flexible and easy adjustment of vibration reduction frequency band, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of a superstructure according to Embodiment 1 of the present invention;

[0021] Figure 2 This is a schematic diagram of a superstructure assembly applied to a spacecraft according to Embodiment 2 of the present invention;

[0022] Figure 3 This is a physical diagram of Example 2 of the present invention;

[0023] Figure 4 Schematic diagram of the bandgap characteristic analysis model in Example 2 of the present invention;

[0024] Figure 5 This is the energy analysis result curve in Example 2 of the present invention;

[0025] Figure 6 This is the bandwidth curve of the superstructure assembly in Example 2 of the present invention. DETAILED DESCRIPTION

[0026] In order to better understand the technical solution of the present invention, the embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. The parts of each structure in the accompanying drawings will be described separately. It is worth noting that the components not shown in the drawings or not described in words are forms known to ordinary technicians in the relevant technical field.

[0027] Figure 1 , Figure 2 Among them, 1-shock reduction structural unit, 2-spiral connecting rod, 3-center position mass block, 4-external frame, 5-elastic overall structure, 6-groove.

[0028] Embodiment 1:

[0029] This embodiment provides a superstructure for the vibration reduction and impact resistance function of a linear separation device, such as Figure 1As shown, it specifically includes: a shock reduction structural unit 1 and an external frame 4; the external frame 4 is a rectangular structure with a hollow cavity therein, the shock reduction structural unit 1 adopts a phononic crystal structure, and is composed of two local resonance units, which are laterally arranged in parallel in the hollow cavity, and the center position of each local resonance unit is a center position mass block 3, and the upper and lower ends of the center position mass block 3 are respectively connected to the upper and lower sides of the external frame 4 through two spiral connecting rods 2 to form a central resonance cavity; the shock reduction structural unit 1 forms a double band gap through local resonance to reduce the explosion separation shock.

[0030] In this embodiment, the upper end of the center position mass block 3 is connected to the first spiral connecting rod, and the lower end is connected to the second spiral connecting rod; the first spiral connecting rod surrounds the center position mass block 3 and is connected to the upper side of the external frame 4, and the second spiral connecting rod surrounds the center position mass block 3 and is connected to the lower side of the external frame 4. The first spiral connecting rod and the second spiral connecting rod are staggered.

[0031] In this embodiment, the cross-sectional dimensions of the external frame 4 are 24.4×11.4 mm, the mass block 3 at the center is a cylinder with a diameter of 5.2 mm, and the thickness of the spiral connecting rod 2 is 0.4 mm.

[0032] Embodiment 2:

[0033] This embodiment provides an application form of the superstructure described in Embodiment 1, which is applied to the explosion separation of an aircraft, such as Figure 2 As shown, the superstructure described in Example 1 is arranged in an array from top to bottom along the longitudinal direction, penetrated in the transverse direction, matched with the length of the linear separation device, and grooves 6 are set on the upper and lower sides, called the elastic integral structure 5, which is connected to the linear separation device of the aircraft through the grooves 6.

[0034] In this example, the elastic integral structure 5 is a nine-layer superstructure array structure with a structural section size of 120.6×24.4mm. The mass block 3 at the center is a cylinder with a diameter of 5.2mm, and the thickness of the spiral connecting rod 2 is 0.4mm. The wall thickness on both sides of the short side direction of the external frame 4 is greater than the thickness at the breaking position of the linear separation device and is designed to be 2mm.

[0035] In this embodiment, the material of the impact reduction structural unit 1 is AlSi10Mg aluminum alloy. The superstructure is preferably prepared by selective laser melting (SLM) using AlSi10Mg aluminum alloy powder. Figure 3 shown.

[0036] In this embodiment, the band gap width of the impact reduction structural unit 1 is obtained by band gap characteristic analysis using solid mechanics simulation, and the specific implementation steps are as follows:

[0037] Step 1: Use solid mechanics simulation to analyze band gap characteristics;

[0038] Step 2: The structural analysis content is to calculate the one-dimensional phononic crystal band gap, so the two-dimensional space dimension is used to simulate and analyze the impact reduction structure unit. The established model is as follows Figure 4 As shown;

[0039] Step 3: The periodic direction of the superstructure model is the Y direction, so periodic boundary conditions are applied on the upper and lower sides of the superstructure model, i.e., in the Y direction;

[0040] Step 4: The superstructure material is aluminum alloy. In the energy band calculation, the aluminum alloy material model selects linear elastic material;

[0041] Step 5: Analyze the 10th-order energy band results of the shock-reducing structural unit, and determine the band gap width of the shock-reducing structural unit based on the 10th-order energy band results of the shock-reducing structural unit.

[0042] In the energy band calculation, the aluminum alloy material model selects linear elastic material. The general linear elastic model of aluminum alloy simulation parameters is shown in Table 1, including density, elastic modulus and Poisson's ratio.

[0043] Table 1 Aluminum alloy simulation material parameters

[0044]

[0045] The analysis results show that the first band gap of the impact reduction structural unit 1 is located between the fourth and fifth energy bands, that is, 1125Hz-1172 Hz, the absolute band gap width is 47Hz, and the corresponding relative band gap width (the ratio of the actual band gap width to the center frequency of the band gap) is 0.041; the second band gap is located between the sixth and seventh order energy band curves, that is, 1270Hz-1354 Hz, the absolute band gap width is 84Hz, and the corresponding relative band gap width is 0.064.

[0046] In order to analyze the basic mechanism of band gap generation, the vibration modes of the structure are as follows Figure 5 As shown in Figure 1, the vibration modes of the fourth, fifth and sixth energy band structures are manifested as the vibration of the oscillator in the internal resonant cavity, and the vibration mode of the seventh energy band is manifested as the vibration of the external frame. This proves that the local resonance shock reduction structure has a suppressive effect on the explosion shock elastic wave within the frequency range. The bandwidth curve of the superstructure is shown in Figure 1. Figure 6 shown.

[0047] It is to be understood that the present invention is described by way of embodiments, and it is known to those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed herein, and embodiments that can fall within the scope of the claims of this application all fall within the scope protected by the present invention.

[0048] The contents not described in detail in the specification of the present invention belong to the common knowledge of those skilled in the art.

Claims

1. A superstructure for the shock absorption and impact resistance of a linear separation device, characterized in that: include: A shock reduction structural unit (1) and an external frame (4); the external frame (4) is a rectangular parallelepiped structure having a hollow cavity therein; the shock reduction structural unit (1) adopts a phononic crystal structure and is composed of two local resonance units, which are arranged in parallel in the hollow cavity; the center position of each local resonance unit is a center position mass block (3); the upper and lower ends of the center position mass block (3) are respectively connected to the upper and lower sides of the external frame (4) through two spiral connecting rods (2) to form a central resonance cavity; the shock reduction structural unit (1) forms a double band gap through local resonance to reduce the explosion separation shock.

2. The superstructure for the shock absorption and impact resistance of the linear separation device according to claim 1 is characterized in that: The upper end of the center position mass block (3) is connected to a first spiral connecting rod, and the lower end is connected to a second spiral connecting rod; the first spiral connecting rod surrounds the center position mass block (3) and is connected to the upper side of the external frame (4); the second spiral connecting rod surrounds the center position mass block (3) and is connected to the lower side of the external frame (4); the first spiral connecting rod and the second spiral connecting rod are alternately surrounded.

3. The superstructure for the shock absorption and impact resistance of the linear separation device according to claim 1, characterized in that: The central position mass block (3) is a cylinder.

4. The superstructure for shock absorption and impact resistance of a linear separation device according to claim 1, characterized in that: The superstructure is arranged in an array from top to bottom along the longitudinal direction and penetrated in the transverse direction to match the length of the linear separation device. Grooves (6) are provided on the upper and lower sides and connected to the linear separation device structure of the aircraft through the grooves (6) for application in the case of explosive separation of the aircraft.

5. The superstructure for the shock absorption and impact resistance of the linear separation device according to claim 4, characterized in that: The cross-sectional dimensions of the external frame (4) are 24.4×11.4 mm, the mass block (3) at the center is a cylinder with a diameter of 5 to 6 mm, and the thickness of the spiral connecting rod (2) is 0.3 to 0.5 mm.

6. The superstructure for the shock absorption and impact resistance of the linear separation device according to claim 5, characterized in that: The cross-sectional dimensions of the external frame (4) are 24.4×11.4 mm, the mass block (3) at the center is a cylinder with a diameter of 5.2 mm, and the thickness of the spiral connecting rod (2) is 0.4 mm.

7. The superstructure for the vibration reduction and impact resistance of the linear separation device according to claim 4, characterized in that: The material of the superstructure is AlSi10Mg aluminum alloy.

8. The superstructure for the vibration reduction and impact resistance of the linear separation device according to claim 4, characterized in that: The first band gap of the shock-reducing structural unit (1) is located between the fourth and fifth energy bands, namely, 1125 Hz-1172 Hz, and the second band gap is located between the sixth and seventh order energy band curves, namely, 1270 Hz-1354 Hz.

9. The superstructure for the vibration reduction and impact resistance of the linear separation device according to claim 4, characterized in that: The wall thickness of both sides of the external frame (4) in the short side direction is greater than the thickness at the fracture position of the linear separation device structure.

10. The superstructure for the shock absorption and impact resistance of the linear separation device according to claim 9, characterized in that: The wall thickness of both sides of the external frame (4) in the short side direction is 2 to 3 mm.

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