CN105987651A - Heat-storage type rocket conformal antenna structure - Google Patents

Abstract

The invention belongs to the technical field of conformal antenna configurations for rockets, and provides a conformal antenna configuration for rockets suitable for long-term high-temperature flight environments, which solves the problem of severe thermal environments experienced by antennas; it includes a base (1), a microstrip plate ( 2), cover plate (3), outer surface (4), mounting surface (5), inner surface (6), mounting screw holes (8), connector (9), thermal storage module (10), gasket ( 11), the first back-shaped groove (12), the second back-shaped groove (13), the third back-shaped groove (14), the gap formed by negative tolerance (15), the frustum of a cone (19) And the microstrip board and the base mounting surface (20), wherein the base (1) and the cover plate (3) are fixed by the screws passing through the mounting screw hole (8) and the periphery of the mounting screw hole (8) is provided with a pad The sheet (11), the microstrip plate (2) is arranged at the center of the cover plate (3), and a negative tolerance is provided between the microstrip plate (2) and the cover plate (3) to form a gap (15).

Description

A Regenerative Rocket Conformal Antenna Configuration

technical field

The invention belongs to the technical field of conformal antenna configurations for rockets, and in particular relates to a conformal antenna configuration and a design method for heat storage type rockets.

Background technique

Due to the limited internal space of the rocket, various microwave communication antennas on the rocket are generally installed conformally with the curved surface of the metal rocket body, and have the characteristics of low profile. They generally include three parts: the base, the microstrip board, and the cover plate, and the total height does not exceed 20mm. The configuration is shown in Figure 1. The supersonic cruise rocket is subjected to a severe aerodynamic heating environment during the long-term flight, and the antenna is also subjected to the following severe thermal environment:

1) The outer surface is directly subjected to pneumatic heating;

2) The installation contact surface is affected by the heat conduction of the metal rocket body;

3) The inner surface is subjected to the convection and radiation of the environment inside the rocket.

Restricted by the material, soldering process, and the working temperature of components such as sockets, the general operating temperature of the antenna is less than 150°C. The use of high-temperature-resistant materials, components, and processes to increase the operating temperature of the antenna will increase the geometric progression of the cost.

On the one hand, there is no heat sink to store heat, and the heat of the antenna cannot be exported; on the other hand, the antenna generally requires good grounding requirements, and the commonly used heat insulation gaskets have poor conductivity. In addition, the space inside the rocket is limited, and the temperature control measures and installation process for the antenna will be greatly restricted, and the cost will be relatively high. Therefore, there are great difficulties in the anti-heat insulation design of the rocket common antenna with high temperature resistance for a long time.

Contents of the invention

The technical problem to be solved by the present invention is to provide a rocket conformal antenna configuration suitable for long-time high-temperature flight environment and solve the problem of severe thermal environment experienced by the antenna.

The technical scheme adopted in the present invention is:

A regenerative rocket conformal antenna configuration, including a base, a microstrip plate, a cover plate, an outer surface, a mounting surface, an inner surface, mounting screw holes, a plug, a heat storage module, a gasket, a first loop Zigzag groove, second zigzag groove, third zigzag groove, negative tolerance forming gap, frustum of cone hole and microstrip board and base mounting surface, wherein the base and cover plate are installed by passing through The screws in the screw holes are fixed with gaskets on the periphery of the mounting screw holes. The microstrip plate is set at the center of the cover plate. The thermal module, the inner ring of the heat storage module is a conical hole, and there is a plug in the middle of the conical hole; the installation surface is set on the edge of the cover plate, and the second back-shaped groove is set between the base and the heat storage module In between, the second back-shaped groove and the heat storage module form the first back-shaped groove, and the second back-shaped groove and the base form the third back-shaped groove.

The four empty grooves in the first back-shaped groove, wherein two parallel empty grooves are respectively provided with two first back-shaped groove connecting beams, and the second back-shaped groove is provided with two The second back-shaped groove connecting beam is perpendicular to the first back-shaped groove connecting beam, and the third back-shaped groove is provided with two third back-shaped grooves perpendicular to the second back-shaped groove connecting beam. The glyph groove connects the beam.

The cover material is a heat-insulating and wave-transmitting material.

The connecting surface of the cover plate and the microstrip plate is designed to be assembled with a negative tolerance.

The beneficial effects of the present invention are:

1. Suitable for long-term high-temperature flight environment;

2. Make the antenna have the best anti-heat insulation performance;

3. The replaceable heat storage module with large heat capacity and the thin-shell packaging structure absorb the heat conducted by each part of the antenna, with slow temperature rise and small temperature difference, adapting to various thermal environments;

4. The back-shaped through-slot of the base and the structure of connecting beams arranged staggered in all directions:

a) High structural strength and simple processing;

b) The temperature in the center is uniform, suitable for feed bias antennas;

c) The heat conduction path is increased, the heat transfer area is reduced, and the hysteresis temperature rise effect is remarkable;

d) Avoid forming a closed space and eliminate the expansion effect of gas;

e) Increase the heat dissipation area of the inner surface;

5. The indented structure of the base avoids contact with the rocket body, and the heat conduction through the gap greatly inhibits the heat conduction effect;

6. The coating structure on the inner surface of the base strengthens the radiation heat dissipation;

7. The mounting hole structure of the conical base connector is convenient for plugging in and out of the connector, and minimizes the impact of the volume and contact area of the thermal storage module;

8. The adhesive structure of the cover plate and the base eliminates the thermal short circuit effect of the screw. The mounting screws are sealed with titanium alloy and high-temperature putty, which can reduce the thermal short-circuit effect to a certain extent;

9. The negative tolerance design of the assembly of the microstrip plate and the cover plate increases the contact thermal resistance and inhibits heat conduction. The microstrip plate and the base are coated with thermal grease design, which reduces the contact thermal resistance and enhances heat conduction;

10. The design of multi-layer gasket increases the contact surface and increases the heat conduction path. Avoid the confined space formed by the indentation of the base, and eliminate the influence of gas expansion.

Description of drawings

Figure 1 is a typical rocket conformal antenna configuration;

Fig. 2 is a configuration schematic diagram of a regenerative rocket conformal antenna;

Fig. 3 is back font structural diagram;

In the figure: 1 base; 2 microstrip board; 3 cover plate; 4 outer surface; 5 installation surface; 6 inner surface; 8 installation screw holes; Back-shaped groove; 13 The second back-shaped groove; 14 The third back-shaped groove; 15 Negative tolerance forms a gap; 16 The first back-shaped groove connecting beam; 17 The second back-shaped groove connecting beam ; 18 The third back-shaped groove connected to the beam; 19 Conical frustum hole; 20 Microstrip board and base mounting surface.

detailed description

Below in conjunction with accompanying drawing and embodiment a kind of that the present invention provides is introduced:

A regenerative rocket conformal antenna configuration, including a base 1, a microstrip plate 2, a cover plate 3, an outer surface 4, a mounting surface 5, an inner surface 6, mounting screw holes 8, sockets 9, and a thermal storage module 10. Gasket 11, first back-shaped groove 12, second back-shaped groove 13, third back-shaped groove 14, negative tolerance forming gap 15, conical frustum hole 19, microstrip plate and base The mounting surface 20, wherein the base 1 and the cover plate 3 are fixed by screws passing through the mounting screw hole 8. The periphery of the mounting screw hole 8 is provided with a gasket 11, and the microstrip plate 2 is arranged at the center of the cover plate 3. , between the microstrip plate 2 and the cover plate 3, there is a negative tolerance to form a gap 15, and the microstrip plate 2 is provided with a thermal storage module 10, the inner ring of the thermal storage module 10 is a frustum of conical hole 19, and the middle of the truncated conical hole 19 There is a socket 9; the installation surface 5 is set on the edge of the cover plate 3, and the second back-shaped groove 13 is set between the base 1 and the heat storage module 10, and the second back-shaped groove 13 is connected with the heat storage module. The module 10 forms the first back-shaped groove 12 , and the second back-shaped groove 13 and the base 1 form the third back-shaped groove 14 .

Four empty grooves in the first back-shaped groove 12, wherein two parallel empty grooves are respectively provided with two first back-shaped groove connecting beams 16, and the second back-shaped groove 13 is provided with There are two second back-shaped groove connecting beams 17 perpendicular to the first back-shaped groove connecting beam 16, and two back-shaped groove connecting beams 17 are arranged in the third back-shaped groove 14 17 vertical third back-shaped grooves connect the beam 18.

The cover material is a heat-insulating and wave-transmitting material.

The connecting surface of the cover plate 3 and the microstrip plate 2 is designed to be assembled with a negative tolerance.

1) Microstrip board

According to the electrical performance requirements of the antenna, determine the material and dimensions of the microstrip board 2.

2) Heat storage module

The large heat capacity of the heat storage module can effectively absorb the heat conducted by the various parts of the antenna, the temperature rises slowly, the temperature difference is small, and it is suitable for various thermal environments. The heat storage module material can be selected according to the flight time and flight thermal environment, metal with better thermal conductivity and larger heat capacity, copper foam with larger phase change latent heat, carbon foam reinforced solid-liquid phase change material or thermal reaction endothermic material Wait. According to experience and thermal analysis, metals can be selected for flight times of 0 to 500s, phase change materials can be selected for flight times of 300 to 800s, and reaction endothermic materials can be selected for flight times >700s. Metal is used as the heat storage module, and the cost is low, such as steel, etc. The phase change material is used as the heat storage module, and the phase change point temperature is required to be lower than the control target temperature with a margin. According to the test and analysis, at least 20°C or more, for example: 150°C control target temperature, 120°C phase change point temperature can be selected butylene glycol etc. The reaction endothermic material is used as a heat storage module and cannot be reused.

According to experience, the size of the heat storage module 10 is generally 1 to 2 times that of the microstrip board. If the heat storage module is too large, the antenna will be too large, which will lose the characteristics of the low profile of the common antenna, and the cover plate will be easily deformed during flight and affect the electrical performance. The thickness of the thermal storage module is related to the thermal conductivity of the selected material, the bigger the better. Taking fatty alcohol phase change materials as an example, the thermal conductivity of the material itself is low. Generally, copper foam or carbon foam is added to enhance thermal conductivity, but the total latent heat is reduced. According to experience, it is generally required that the thermal conductivity should not be lower than 5W/m.k, and the filling rate of phase change materials should not be lower than 80%. Therefore, the heat storage module should not be too thick, generally not greater than 20mm according to experience.

3) Base

The base material can choose metal materials with poor thermal conductivity such as stainless steel or titanium alloy. The thermal conductivity of titanium alloy is smaller and the effect is better. However, due to the difficulty of processing and high cost, stainless steel is generally selected.

According to experience, the size of the base 1 is generally twice that of the heat storage module. According to the function, the base is divided into a central heat storage module package structure part and a round-shaped groove structure part around it.

For the heat storage module packaging structure, the upper cover is designed as a thin-walled structure to enhance heat transfer and reduce the temperature difference, for example, 0.5-1mm, so that the temperature difference in the center is generally less than 1°C, which can adapt to various feeding bias antennas. The upper cover is screwed with silicone rubber seal, which makes the heat storage module replaceable. According to the position of the power feed, the installation hole 19 of the conical base connector is designed. The small circle at the bottom can envelop the connector 9, and the large circle at the top can facilitate the insertion and removal of high-frequency cables, which minimizes the volume and contact area of the heat storage module. The impact on the effective latent heat and heat transfer of the heat storage module is correspondingly reduced.

The back-shaped slot structure, the back-shaped through-slot of the base and the structure of connecting beams arranged staggered in all directions: a) high structural strength, simple processing; b) uniform temperature in the center, suitable for feed bias antenna; c) The heat conduction path is increased, the heat transfer area is reduced, and the hysteresis temperature rise effect is remarkable; e) the formation of a closed space is avoided, and the expansion effect of the gas is eliminated; f) the heat dissipation area of the inner surface is increased. According to experience, the number of grooves is generally <5, which is related to the size, structural strength, and processing difficulty of the base. The more grooves, the smaller the corresponding groove width, the weaker the strength, and the greater the processing difficulty. The connecting beams are alternately arranged on the short side, long side, front and back of the base, ensuring that the outermost back-shaped through-slot connecting beam is the short side, and the innermost back-shaped through-slot connecting beam is on the back of the base. In order to reduce the contact area between the base and the cover plate, the connecting beam of the back-shaped through-slot on the front of the base is offset downward. The offset is determined by calculation and analysis, even though the temperature of the back-shaped through-slot is the lowest at the connecting beam.

The base is indented about 1mm from the cover plate to avoid contact with the rocket body around the base, and the heat conduction through the gap can significantly suppress the heat conduction effect. After theoretical calculation and experimental analysis, the above measures can reduce the temperature of the microstrip plate by about 10°C;

The connecting surface of the base and the microstrip board is coated with thermal grease to reduce the contact thermal resistance and enhance the heat exchange, so that the heat of the microstrip board can be effectively conducted to the heat storage module in the base, reducing the contact between the base and the microstrip board. temperature difference.

The inner surface of the base is coated with a high emissivity coating (such as black paint), which strengthens radiation heat dissipation.

4) Cover plate

The material of the cover plate is heat-insulating and wave-transmitting materials, such as polytetrafluoroethylene, polyimide, silicon nitride, etc., which are required to adapt to the aerodynamic heating environment.

The outer surface of the cover plate is conformal to the rocket body, and the inner surface of the cover plate is attached to the base. Under the premise of meeting the mechanical performance requirements, the thickness of the central part of the cover plate is calculated and analyzed. Even if the heat transferred from the outer surface to the heat storage module is basically the same as the heat transferred from the installation surface to the heat storage module, the temperature in the thickness direction of the heat storage module is uniform. The calculation and analysis of the thickness of the connection hole of the cover plate determined that even if the heat transferred to the screw from the outer surface is basically the same as the heat transferred to the screw from the mounting surface, the lowest temperature of the mounting screw is near the connection surface.

The connection surface of the cover plate and the microstrip board is designed to be assembled with a negative tolerance, the contact is not completed, the contact thermal resistance is increased, the heat conduction is suppressed, the heat transferred from the cover plate to the microstrip board is reduced, and the temperature difference between the cover plate and the microstrip board is increased.

The cover plate and the base are bonded with high-temperature resistant silicone rubber, and the mounting screws can also play an auxiliary role in fixing. The thermal short-circuit effect of the screw is eliminated, and the severe aerodynamic heating is prevented from being conducted to the inside of the antenna through the screw. After theoretical calculation and experimental analysis, the thermal short-circuit of one screw affects the temperature of the microstrip board by about 5°C. The contact surface around the cover plate and the rocket body is sealed with high temperature resistant silicon rubber.

5) Gasket

The gasket material can be selected from a material with good electrical conductivity and low thermal conductivity, such as titanium alloy. According to the design gasket thickness of the rocket body installation space, when the thickness is large, it can be designed as a multi-layer gasket. The multi-layer gasket design increases n+1 contact surfaces, correspondingly generates n+1 contact thermal resistances, increases the heat conduction path, avoids the closed space formed by the indentation around the base and the rocket body, and eliminates the influence of gas expansion ;

6) screw

The mounting screws are made of titanium alloy and other metal materials with poor thermal conductivity. After installation, the screw heads are sealed with high-temperature putty to make the shape smooth. Prevent the screw head from being directly subjected to aerodynamic heating, and reduce the thermal short circuit effect of the screw to a certain extent. After theoretical calculation and experimental analysis, one screw with the above measures can reduce the temperature of the microstrip plate by about 3 °C.

Claims (4)

1. A regenerative rocket conformal antenna configuration, characterized in that: comprising a base (1), a microstrip plate (2), a cover plate (3), an outer surface (4), a mounting surface (5), Inner surface (6), mounting screw holes (8), connectors (9), heat storage module (10), gasket (11), first zigzag groove (12), second zigzag groove (13), the third back-shaped groove (14), the gap formed by the negative tolerance (15), the conical frustum hole (19) and the microstrip board and the base mounting surface (20), wherein the base (1) and the cover plate (3) are fixed by the screws passing through the mounting screw hole (8). The periphery of the mounting screw hole (8) is provided with gaskets (11), and the microstrip plate (2) is located on the cover plate (3) At the center position, a negative tolerance gap (15) is provided between the microstrip plate (2) and the cover plate (3), and a heat storage module (10) is provided on the microstrip plate (2), and the heat storage module (10 ) inner ring is a frustum of conical hole (19), and a socket (9) is arranged in the middle of the frustum of conical hole (19); 13) Located between the base (1) and the heat storage module (10), the second back-shaped groove (13) and the heat storage module (10) constitute the first back-shaped groove (12), the second The two back-shaped grooves (13) and the base (1) constitute the third back-shaped groove (14). 2. A regenerative rocket conformal antenna configuration according to claim 1, characterized in that: the four empty slots in the first back-shaped groove (12), of which two parallel empty slots Two first back-shaped groove connecting beams (16) are respectively arranged in the second back-shaped groove (13) and two are vertical to the first back-shaped groove connecting beam (16) in the second back-shaped groove (13). Two back-shaped grooves connecting beams (17), the third back-shaped grooves (14) are provided with two vertical third back-shaped grooves connecting beams (17) with the second back-shaped grooves. Beam (18). 3 . The heat storage rocket conformal antenna configuration according to claim 1 , wherein the cover plate material is a heat-insulating and wave-transmitting material. 4 . 4. A regenerative rocket conformal antenna configuration according to claim 1, characterized in that: the connecting surface of the cover plate (3) and the microstrip plate (2) is designed to have a negative assembly tolerance.