JP6971906B2 - Flying body - Google Patents

Description

The present invention relates to a radome for a flying body that protects a flying body antenna.

A radome for the flying object is provided at the tip of the flying object to fly toward the target by radio wave guidance to protect the antenna for the flying object. The radome for the flying body includes a radome body and a ring fixed to the radome body. The radome body is fixed to the airframe of the flying object via the ring.

Many flying bodies reach supersonic speeds or hypersonic speeds within a short time of a few seconds from the start of flying. Therefore, it is necessary to protect each component inside the flyer from aerodynamic heating. For example, in the technique described in Patent Document 1, the radome body is provided with a radome body, a ring, and a guide for providing a predetermined space on the outer periphery of a joint portion between the radome body and the ring, and heat generated by aerodynamic heating is generated. , Prevents inflow into the ring and radome joints.

Jikkenhei 5-71699 Gazette

However, the technique described in Patent Document 1 described above does not consider reducing the amount of heat inflow to the antenna due to the generation of aerodynamic heating. In the technique described in Patent Document 1, the heat generated by aerodynamic heating is transferred from the radome body to the machine body via the ring. In the airframe, which takes into consideration the high-density mounting of each component inside the airframe, the airframe and the antenna are thermally connected, so the heat transferred to the airframe is transferred to the antenna.

The present invention has been made in view of the above, and an object of the present invention is to obtain a radome for a flying body capable of reducing the amount of heat inflow to the antenna due to the generation of aerodynamic heating.

In order to solve the above-mentioned problems and achieve the object, the flying object according to the present invention is the airframe, the radome body joined to the tip of the airframe, and the joint between the airframe and the radome body. An antenna fixed to the inside of the fuselage, a ring provided at the joint, one end fixed to the rear end of the radome body, and the other end joined to the tip of the fuselage , provided between the ring and the fuselage. It is provided with a spacer in which two or more layers of materials having different melting points are laminated.

According to the present invention, there is an effect that the amount of heat inflow to the antenna due to the generation of aerodynamic heating can be reduced.

Cross-sectional view of the tip of a flying object provided with a radome for the flying object according to the embodiment of the present invention. Enlarged sectional view of part X shown in FIG. The figure for demonstrating the operation state when the radome of the flying object shown in FIG. 1 does not have a spacer. The figure for demonstrating the operation state when the radome of the flying object shown in FIG. 1 is provided with a spacer. A graph showing the relationship between the flight time of the flying object and the temperature of the antenna shown in FIG.

Hereinafter, the radome for a flying body according to the embodiment of the present invention will be described in detail with reference to the drawings. The present invention is not limited to this embodiment.

Embodiment.
FIG. 1 is a cross-sectional view of a tip portion of a flying object provided with a radome for the flying object according to the embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view of a portion X shown in FIG.

The flying object 1 shown in FIGS. 1 and 2 flies toward the target by radio wave guidance. The airframe 1 includes an airframe 2, an antenna 3 for the airframe, a radome 4 for the airframe, and a heat insulating material 5. The radome 4 for a flying body includes a radome main body 6, a ring 7, and a spacer 8. In the following description, the flying antenna 3 is simply referred to as an antenna 3. Further, in the following description, the radome 4 for a flying body is simply referred to as a radome 4.

The tip portion of the machine body 2 has a shape in which a second cylinder 2b having an outer diameter smaller than the outer diameter of the first cylinder 2a is connected to the tip of the first cylinder 2a. The radome 4 is joined to the upper surface 2aa of the first cylinder 2a and the side surface 2ba of the second cylinder 2b. Hereinafter, the portion to be joined is referred to as a joint portion Y. The machine body 2 is formed by using a material having a coefficient of thermal expansion of about 10 × 10 ⁻⁶ / ° C. to 30 × 10 ^{−6 / ° C. such as iron or aluminum.} The antenna 3 detects the target. The antenna 3 is provided at the tip of the machine body 2. Specifically, the antenna 3 is provided inside the second cylinder 2b of the machine body 2. The heat resistant temperature of the antenna 3 is, for example, 150 ° C. The radome 4 protects the antenna 3.

The radome body 6 has a streamlined shape with a sharp tip of the outer shell, the outer diameter of the outer shell smoothly expands from the tip to the rear end, and the rear end is open and hollow. Since the radome body 6 needs to transmit radio waves transmitted and received by the antenna 3, it is formed by using a dielectric material. As the dielectric material, _{ceramics such as alumina (Al 2} O ₃ ), cordillite ( ₂ MgO ・ 2 Al 2 O ・ 5SiO ₂ ), fused silica (SiO ₂ ) or silicon nitride (Si ₃ N ₄ ) sintered body, Alternatively, fiber reinforced plastics (FRP: also called Fiber Reinforced Plastics) can be mentioned. In the present embodiment, the radome main body 6 is ^{formed by using ceramics having a thermal expansion coefficient of 5 × 10 −6} / ° C. or less, which is excellent in heat resistance and thermal impact resistance. The radome body 6 is joined to the machine body 2 via the ring 7 and the spacer 8 and fixed to the machine body 2.

The ring 7 is fixed to the rear end portion of the radome body 6 by the adhesive 9. The ring 7 is fixed to the rear end of the radome body 6 so that the rear end of the radome body 6 is extended rearward. The ring 7 is provided at the joint portion Y. One end of the ring 7 is fixed to the rear end of the radome body 6, and the other end is joined to the upper surface 2aa of the first cylinder 2a of the machine body 2. The ring 7 has an FRP having a high rigidity and a relatively low coefficient of thermal expansion having a coefficient of thermal expansion of about 4 × ^10-6 / ° C to 10 × ^10-6 / ° C, or a coefficient of thermal expansion of 1 × ^10-6 / ° C to 5 It is formed by using Invar, which is a low thermal expansion metal of about × 10 ^{-6 / ° C.}

The spacer 8 is provided at the joint portion Y. The spacer 8 is provided between the machine body 2 and the ring 7. Specifically, the spacer 8 is provided between the ring 7 and the side surface 2ba of the second cylinder 2b of the machine body 2. The spacer 8 is a material having a thermal conductivity lower than that of the machine body 2, and is formed by laminating two or more layers of materials having different melting points. The material of each layer of the spacer 8 is a resin or an alloy. In this embodiment, the spacer 8 includes a first layer 8a, a second layer 8b, and a third layer 8c, which are layers of resins or alloys having different melting points, respectively. The machine body 2, the spacer 8, the ring 7, and the radome body 6 are stacked in the same direction as the stacking direction of each layer of the spacer 8. Examples of the resin forming the spacer 8 include acrylic having a melting point of about 100 ° C. and polycarbonate having a melting point of about 150 ° C. Examples of the alloy forming the spacer 8 include a tin alloy having a melting point of about 250 ° C. among tin alloys, and a zinc alloy having a melting point of 200 ° C. to 300 ° C. among zinc alloys. The spacer 8 may be formed by laminating the above-mentioned resin layer and the above-mentioned alloy layer.

It is preferable that the spacer 8 is not melted by the aerodynamic heating of the mother machine carrying the flying object 1 but is melted by the aerodynamic heating of the flying body 1 during the free flight. For example, the temperature of the spacer 8 rises to 100 ° C due to the aerodynamic heating of the mother machine carrying the flying object 1, and the temperature of the spacer 8 rises to 150 ° C due to the aerodynamic heating of the flying body 1 during free flight. Suppose it rises. In this case, by forming the spacer 8 without using acrylic having a melting point of about 100 ° C. among the above-mentioned spacer materials, it is possible to prevent the spacer 8 from melting when the mother machine is blown.

The heat insulating material 5 covers the rear end portion of the radome body 6, the ring 7, and the machine body 2. The heat insulating material 5 prevents the temperature inside the flying body 1 from rising.

FIG. 3 is a diagram for explaining an operating state when the radome of the flying object shown in FIG. 1 does not have a spacer. FIG. 4 is a diagram for explaining an operating state when the radome of the flying object shown in FIG. 1 includes a spacer.

At the time of flying the flying body 1, aerodynamic heating A is generated on the outer periphery of the radome main body 6 and the heat insulating material 5. When the radome 4 does not have the spacer 8, as shown in FIG. 3, the heat B generated by the aerodynamic heating A is transmitted to the antenna 3 by heat conduction through the ring 7 and the machine body 2, and the temperature of the antenna 3 rises. It may rise and the temperature of the antenna 3 may exceed the heat resistant temperature. Further, when the airframe 2 thermally expands due to the heat B transferred to the airframe 2, thermal stress C is generated, the ring 7 and the radome body 6 are pushed up, and the radome body 6 formed by using a brittle material such as ceramics is destroyed. there is a possibility.

In the present embodiment, since the redome 4 includes the spacer 8, the heat D generated by the aerodynamic heating A is transferred to the antenna 3 by heat conduction through the ring 7, the spacer 8 and the machine body 2, as shown in FIG. Although it is transmitted, the thermal conductivity of the spacer 8 is lower than the thermal conductivity of the machine body 2, and since the spacer 8 is melted by the heat D transmitted to the spacer 8, the latent heat E at the time of melting causes the heat D flowing into the antenna 3 to flow. The amount of heat is reduced, and the temperature rise of the antenna 3 is suppressed. Further, the heat D transmitted to the spacer 8 gradually melts the layers 8a, 8b, 8c having different melting points of the spacer 8, and the spacer 8 becomes thinner, so that the machine body 2 thermally expands and is generated in the radome body 6. The thermal stress F is relaxed. If the spacer 8 has only one layer, the spacer 8 may melt at a time when the melting point is exceeded, and a gap may be formed between the ring 7 and the machine body 2. Therefore, in the present embodiment, the spacer 8 is formed by laminating two or more layers of materials having different melting points.

FIG. 5 is a graph showing the relationship between the flight time of the flight body shown in FIG. 1 and the temperature of the antenna. In FIG. 5, the case where the radome 4 does not include the spacer 8 is indicated by the alternate long and short dash line G, and the case where the radome 4 includes the spacer 8 is indicated by the solid line H. The temperature Ta is the maximum temperature of the antenna 3 reached by aerodynamic heating of the mother machine carrying the flying object 1. The temperature T1 is the melting point of the first layer 8a of the spacer 8, the temperature T2 is the melting point of the second layer 8b of the spacer 8, and the temperature T3 is the melting point of the third layer 8c of the spacer 8. The temperature Tb is the heat resistant temperature of the antenna 3.

As shown by the one-point chain line G in FIG. 5, in the flying object 1 to fly at supersonic speed or extreme supersonic speed, the aerodynamic heating A at the time of flying causes the radome body 6 to pass through the ring 7 and the aircraft 2. Although heat is transferred to the antenna 3 and is affected by the heat capacity of each component of the flying body 1, the temperature of the antenna 3 generally continues to increase as the flying time increases.

As shown by the solid line H in FIG. 5, since the radome 4 according to the present embodiment includes the spacer 8, the resin or alloy is formed by the latent heat E at the time of melting of the layers 8a, 8b, 8c having different melting points of the spacer 8. While the resin is melting, the temperature rise of the antenna 3 is suppressed. As a result, the temperature of the antenna 3 can be made less likely to exceed the heat resistant temperature Tb even when the flying object 1 has a high speed and a long range, as compared with the case where the radome 4 does not have the spacer 8.

The configuration shown in the above-described embodiment shows an example of the content of the present invention, can be combined with another known technique, and is one of the configurations as long as it does not deviate from the gist of the present invention. It is also possible to omit or change the part.

1 flyer, 2 machine, 2a first cylinder, 2a top surface, 2b second cylinder, 2ba side surface, 3 flyer antenna, 4 flyer radome, 5 insulation, 6 radome body, 7 ring , 8 spacers, 8a first layer, 8b second layer, 8c third layer, 9 adhesives, Y joints.

Claims (6)

With the aircraft
The radome body joined to the tip of the machine and
An antenna that is a joint between the airframe and the radome body and is fixed inside the airframe.
A ring provided at the joint, one end of which is fixed to the rear end of the radome body and the other end of which is joined to the tip of the machine.
A spacer provided between the ring and the airframe, and two or more layers of materials having different melting points are laminated .
A flying body characterized by being equipped with. The spacer has a first layer in contact with the ring, a third layer in contact with the airframe, and a second layer between the first layer and the third layer.
The thermal conductivity of the first layer, the thermal conductivity of the second layer, and the thermal conductivity of the third layer are lower than the thermal conductivity of the aircraft.
The flying object according to claim 1 , wherein the melting point of the second layer is higher than the melting point of the first layer, and the melting point of the third layer is higher than the melting point of the second layer. The tip portion of the machine body is connected to a first cylindrical portion and a second cylindrical portion which is arranged on the tip end side of the first cylindrical portion and has an outer diameter smaller than that of the first cylindrical portion. Has a good shape
The antenna is fixed inside the second cylindrical portion, and the antenna is fixed.
The flyer according to claim 1 or 2 , wherein the spacer is provided on the outside of the second cylindrical portion, and the ring is provided on the spacer . The flyer according to claim 1, wherein the material of each layer of the spacer is a resin or an alloy . The flyer according to any one of claims 1 to 4, further comprising a rear end portion of the radome body, the ring, and a heat insulating material covering the airframe . Each layer of the spacer is characterized in that it does not melt by the aerodynamic heating of the mother machine carrying the flying object, but by the aerodynamic heating of the flying object during free flight. The flying object according to any one of claims 1 to 5.

Images