Flexible energetic film planar multipoint ignition device

Abstract

The present application belongs to the technical field of solid engine ignition, and particularly relates to a flexible energetic film plane multi-point ignition device. The device comprises an upper ignition unit layer and a lower output unit layer. The ignition unit layer comprises a hollow polyimide (PI) film and a plurality of semiconductor bridge ignition chips connected by a series circuit and arranged on the polyimide (PI) film. The output unit layer comprises a PET film and an energetic film printed on the PET film by 3D printing. The main body of the semiconductor bridge ignition chip arranged on the polyimide (PI) film is embedded in the energetic film. Compared with the BPN, the present application can improve the burning rate by more than ten times, which is helpful to realize the rapid ignition of propellant.

Description

Technical Field

[0001] This invention belongs to the field of solid rocket motor ignition technology, specifically relating to a flexible energetic thin film planar multi-point ignition device. Background Technology

[0002] With the development of long-range and miniaturized weapons and ammunition, solid rocket motors widely adopt propellant with large length-to-diameter ratios and high charge-to-weight ratios. These motors have small initial free volumes and primarily employ end-face combustion of the propellant. This type of engine requires an ignition system with low initial free volume, characterized by low ignition impact, high ignition stability, no residue, simple structure, and ease of maintenance.

[0003] Conventional solid rocket motors employ basket-type, small rocket-type, or ring-shaped propellant box-type ignition devices, with pre-reserved installation positions in the engine combustion chamber. Based on the ignition mode of "multi-stage energy transfer and step-by-step amplification," they rely on the high-temperature and high-pressure gas generated by the main charge to ignite the solid propellant. However, this has gradually exposed safety issues such as high ignition impact, easy cracking of the propellant, irregular burning surfaces not igniting in sequence, and insufficient ignition stability, making it difficult to meet the ignition requirements of the propellant charge. Summary of the Invention

[0004] The purpose of this invention is to provide a flexible energetic thin film planar multi-point ignition device.

[0005] The technical solution to achieve the purpose of this invention is: a flexible energetic thin film planar multi-point ignition device, comprising an ignition unit layer and an output unit layer arranged vertically;

[0006] The ignition unit layer includes a perforated polyimide (PI) film and multiple semiconductor bridge ignition chips that are spaced apart on the polyimide (PI) film and connected by a series circuit.

[0007] The output unit layer includes a PET film and an energetic film 3D printed on the PET film;

[0008] The main body of the semiconductor bridge ignition chip, which is disposed on a polyimide (PI) film, is embedded in the energetic film.

[0009] Furthermore, the polyimide (PI) film has an outer circular frame and an inner cross-shaped frame integral with the outer circle. The number of semiconductor bridge ignition chips is 5, which are respectively set at the center of the cross-shaped frame and at the intersection of the circular frame and the cross-shaped frame.

[0010] Furthermore, the thickness of the polyimide (PI) film is 0.05 mm to 0.2 mm.

[0011] Furthermore, the semiconductor bridge ignition chip has a resistance of 1±0.1Ω, which meets the requirement that it will not ignite within 5 minutes at 1A and 1W, and the ignition time is no more than 5ms.

[0012] Furthermore, the material used for printing energetic films is nano-aluminum powder / nano-copper oxide / polyvinylidene fluoride Al-CuO-PVDF.

[0013] Furthermore, the active content of the nano-aluminum powder is 60%-75%, and the average particle size is 50-100nm; the average particle size of the nano-copper oxide is 40-100nm; the equivalent ratio of nano-aluminum powder to nano-copper oxide is 1-2; the PVDF content is 4%-10% of the mass fraction of the energetic film; and the thickness of the energetic film is 0.05mm-0.9mm.

[0014] Furthermore, the energetic thin film has a microporous structure with a pore size of (0-0.746) mm × (0-0.961) mm.

[0015] Furthermore, the semiconductor bridge ignition chip is fixed to the polyimide (PI) film by soldering, and the polyimide (PI) film and the energetic film are bonded together by spraying a compatible adhesive.

[0016] Furthermore, the number of semiconductor bridge ignition chips is 5-19, with one located in the center of the cross-shaped frame and the rest evenly distributed on the circumferential frame.

[0017] Compared with the prior art, the significant advantages of this invention are:

[0018] (1) The overall design involves 3D printing a nano-aluminothermic agent (Al-CuO-PVDF) film onto a PET film, and then deploying multiple semiconductor bridge ignition chips on a flexible, perforated PI film. The two are then tightly bonded together using a compatible adhesive. Using a constant current source, the semiconductor bridge ignition chips can ignite the nano-aluminothermic agent film within 50ms at a current of 6A. Simultaneously, the nano-aluminothermic agent film achieves stable ignition through the perforated PI film layer, ensuring the ignition of the downstream propellant.

[0019] (2) To ensure ignition reliability, the ignition device of the present invention adopts a design concept of simultaneous ignition of multiple semiconductor bridge ignition chips, with a total of 3-5 ignition chips radially and a total of 5-19 ignition chips overall. Compared with a planar igniter with a single ignition chip, the burning rate can be increased by 3-5 times.

[0020] (3) The ignition device of the present invention uses nano-aluminothermic agent (Al-CuO-PVDF) as the main material, taking advantage of its high reaction rate and large heat release. Compared with the traditional BPN ignition agent, the amount of the agent required is greatly reduced from hundreds of grams to a few grams, while the burning rate is increased from tens of millimeters per second to hundreds of millimeters per second.

[0021] (4) The ignition device of the present invention uses PI film with a thickness of 0.05-0.20mm, PET film with a thickness of 0.10-0.30mm, and nano aluminothermic agent (Al-CuO-PVDF) film with a thickness of 0.05-0.90mm. All of them have flexible planar characteristics and can be pasted on the surface of propellant of any shape. They can effectively reduce ignition impact, improve the high-altitude ignition reliability of dual-pulse engines, and are expected to solve the problem of difficult ring groove ignition of strategic engines and reduce the design difficulty of ignition device. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the planar multi-point ignition device of the present invention.

[0023] Figure 2 This is a physical diagram of the ignition unit layer in the planar multi-point ignition device of the present invention.

[0024] Figure 3 This is a physical diagram of the output unit layer in the planar multi-point ignition device of the present invention.

[0025] Figure 4 This is an oscilloscope image of the ignition unit layer igniting the output unit layer in the ignition device of the present invention.

[0026] Figure 5 This is a high-speed linear combustion image of the energetic thin film in the output unit layer of the ignition device of the present invention.

[0027] Explanation of reference numerals in the attached figures:

[0028] 1-Polyimide (PI) film, 2-Semiconductor bridge ignition chip, 3-Enabled film, 4-PET film. Detailed Implementation

[0029] The present invention will now be described in further detail with reference to the accompanying drawings.

[0030] like Figure 1 As shown, a flexible energetic thin-film planar multi-point ignition device comprises two parts: an ignition unit layer and an output unit layer.

[0031] The ignition unit layer includes a polyimide PI film 1 and a semiconductor bridge ignition chip 2; the semiconductor bridge chip is welded onto the polyimide PI film 1 to achieve a tight bond between the components.

[0032] The output unit layer includes an energetic thin film 3 (nano-aluminum powder / nano-copper oxide / polyvinylidene fluoride (nAl-nCuO-PVDF)) prepared by 3D printing method and a PET film 4.

[0033] The physical diagram of the ignition unit layer is shown below. Figure 2As shown, the thickness of the polyimide PI film 1 is 0.10 mm. The polyimide PI film 1 has a hollow structure. Except for the necessary conductive lines on the polyimide PI film 1, the rest are hollow structures. The semiconductor bridge ignition chip 2 is arranged at the crisscrossing position of the PI film and at the center position.

[0034] The semiconductor bridge ignition chip 2 has a resistance of 1Ω, meeting the requirement of not igniting within 5 minutes at 1A and 1W, with an ignition time not exceeding 5ms. There are 5 semiconductor bridge ignition chips 2, connected in series to ensure synchronous multi-point ignition.

[0035] Output cell layer physical diagram as follows Figure 3 As shown, the active content of the nano-aluminum powder in the energetic film 3 is 65%, with an average particle size of 50 nm; the average particle size of the nano-copper oxide is 40 nm. The equivalent ratio of nano-aluminum powder to nano-copper oxide in the energetic film 3 is 2, the PVDF content is 4% of the mass fraction of the energetic film, and the thickness of the energetic film 3 is 0.15 mm. The energetic film 3 uses a microporous structure with a pore size of 0.345 × 0.548 mm.

[0036] The energetic film 3 is printed on the PET film 4 using a 3D printing device. The semiconductor bridge ignition chip 2 is fixed on the polyimide PI film 1 by soldering. The polyimide PI film 1 and the energetic film 3 are tightly bonded by spraying a large area of ​​compatible adhesive.

[0037] Under constant current of 6A / 50ms, the ignition unit layer successfully ignited the output unit layer, as follows: Figure 4 As shown, both electrical and optical signals were recorded on the oscilloscope, with an ignition delay of 1.90 ms. Meanwhile, Figure 5 The image shows the linear combustion propagation of the energetic thin film used, with a burning rate of up to 723.21 mm / s, indicating that the burning rate of the energetic thin film prepared by 3D printing is more than ten times higher than that of BPN, which helps to achieve rapid ignition of the propellant.

Claims

1. A flexible energetic thin-film planar multi-point ignition device, characterized in that, This includes an ignition unit layer and an output unit layer arranged vertically; The ignition unit layer includes a hollowed-out polyimide PI film (1) and a plurality of semiconductor bridge ignition chips (2) that are connected by a series circuit and spaced on the polyimide PI film (1); The output unit layer includes a PET film (4) and an energetic film (3) 3D printed on the PET film (4); The main body of the semiconductor bridge ignition chip (2) disposed on the polyimide PI film (1) is embedded in the energetic film (3).

2. The flexible energetic thin film planar multi-point ignition device according to claim 1, characterized in that, The polyimide PI film (1) has a circular frame on the outer periphery and a cross-shaped frame on the inner periphery that is integral with the circular frame. The number of semiconductor bridge ignition chips (2) is 5, which are respectively set at the center of the cross-shaped frame and at the intersection of the circular frame and the cross-shaped frame.

3. The flexible energetic thin film planar multi-point ignition device according to claim 2, characterized in that, The thickness of the polyimide PI film (1) is 0.05 mm to 0.2 mm.

4. The flexible energetic thin film planar multi-point ignition device according to claim 3, characterized in that, The semiconductor bridge ignition chip (2) has a resistance of 1±0.1Ω, which meets the requirement that it does not ignite within 5 minutes with 1A1W, and the ignition time is no more than 5ms.

5. The flexible energetic thin film planar multi-point ignition device according to claim 4, characterized in that, The material used for printing energetic films (3) is nano aluminum powder / nano copper oxide / polyvinylidene fluoride Al-CuO-PVDF.

6. The flexible energetic thin film planar multi-point ignition device according to claim 5, characterized in that, The active content of the nano-aluminum powder is 60%-75%, and the average particle size is 50-100nm; the average particle size of the nano-copper oxide is 40-100nm; the equivalent ratio of nano-aluminum powder to nano-copper oxide is 1-2; the PVDF content is 4%-10% of the mass fraction of the energetic film; and the thickness of the energetic film is 0.05mm-0.9mm.

7. The flexible energetic thin film planar multi-point ignition device according to claim 6, characterized in that, The energetic thin film (3) has a microporous structure with a pore size of (0-0.746) mm × (0-0.961) mm.

8. The flexible energetic thin film planar multi-point ignition device according to claim 7, characterized in that, The semiconductor bridge ignition chip (2) is fixed on the polyimide PI film (1) by soldering. The polyimide PI film (1) and the energetic film (3) are bonded by spraying a compatible adhesive.

9. The flexible energetic thin film planar multi-point ignition device according to claim 8, characterized in that, The number of semiconductor bridge ignition chips is 5-19, with one located in the center of the cross-shaped frame and the rest evenly distributed on the circumferential frame.

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