JPH01229800A - Radiator - Google Patents

Abstract

PURPOSE:To obtain a lighter radiator which enables automatic temperature control by means of a structure member composed of only a radiating board by closely attaching the radiating board made of a superconducting material to the member to be heat released of an artificial satellite. CONSTITUTION:A radiating board 13 is formed with a superconducting material and is closely attached to the surface on the space 12 side of a base plate 11 so that heat is surely transmitted from the base plate 11. Hence, when the temperature of the base plate 11 rises transmitting heat to the radiating board 13, the heat radiating quantity is small until the temperature of the radiating board 13 reaches a superconduction transition temperature, while getting larger as the temperature gets higher from that temperature. As the base plate 11 is cooled by the radiating board 13, the radiating board again returns to a superconducting condition making it hard to release the heat of the base plate 11. Thereby, the temperature of the base plate 1 can be automatically controlled, realizing automatic temperature control by means of a structure member of only the radiating board 13, to obtain a lighter radiator.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a heat radiator used in equipment used in outer space such as artificial satellites.

[Conventional technology]

The temperature of an artificial satellite (hereinafter simply referred to as a satellite) is determined by the degree to which the surface material of the satellite takes in solar energy and the degree to which it releases thermal energy, and is regulated by selecting surface materials that have the ability to obtain the desired temperature. ing. Furthermore, in order to actively adjust the temperature of a satellite in outer space, a thermal looper as shown in FIGS. 3(a) and 3(b) is used. This thermal looper is Mamoru! It is attached to the surface and controls the amount of radiant heat radiated from the satellite surface by opening and closing blades, which will be described later. In the figure, 1 is a pace plate as a surface member of the satellite, 2 is outer space, 3 is is a thermal looper, and this thermal looper 3 is fixed to the pace plate 1, and is rotatably attached to the side frame 3a surrounding the heat radiation surface 1a of the pace plate 1 via an actuator 3b. It is composed of a blade 3c. The actuator 3b may be of a structure that rotates the blade 3c by utilizing the expansion and contraction of a bimetal (not shown) depending on the temperature of the pace plate 1, for example, and rotates the blade 3C in response to the temperature of the pace plate 1. It has the ability to rotate. That is, when the temperature of the satellite increases, the heat is conducted to the pace plate 1, and the actuator 3b rotates the blade 3c according to the temperature, so the pace plate 1 is exposed to the outer space 2). , heat will be dissipated by thermal radiation. Note that A in the figure indicates radiant heat.

[Problem to be solved by the invention]

However, in the thermal louver 3 configured in this manner, the amount of heat radiation is controlled by opening and closing the blade 3C, making adjustment of the actuator 3b complicated. In addition, the equipment mounted on the satellite is becoming smaller and smaller.
There is a demand for light weight, and in order to obtain the necessary amount of heat dissipation in the conventional thermal louver 3, the pace plate 1 is required.
There is a limit to how small the heat dissipation surface 1a of the thermal louver 3 can be made, and therefore there is a problem in that each component of the thermal louver 3 cannot be made small and compact.

[Means to solve the problem]

A heat radiator according to the present invention has a heat radiating plate made of a superconducting material closely attached to a heat radiating member of an artificial satellite.

[Effect]

Due to the property of superconducting materials that the emissivity changes with the superconducting transition temperature, when the temperature of the heat sink increases above the superconducting transition temperature, the thermal radiation I increases and the amount of heat radiation increases, and when the temperature of the heat radiated member decreases, the heat sink The amount of thermal radiation will also be reduced.

〔Example〕

Hereinafter, its configuration and the like will be explained in detail with reference to embodiments shown in the drawings.

FIG. 1 is a side sectional view showing a heat sink according to the present invention, and FIG. 2 is a graph showing the temperature dependence of infrared emissivity in a superconductor. In these figures, 11 is a pace plate as a heat radiated member of an artificial satellite, 12 is outer space, and 13 is
is a heat dissipation plate for controlling the temperature of the pace plate 11, and this heat dissipation plate 13 is made of a superconducting material to ensure that heat is conducted from the base plate 11 to the surface of the base plate 11 on the outer space 12 side. It is closely attached as if it were Note that A in the figure indicates radiant heat.

Generally, the heat radiation characteristic of a radiator is expressed as Q"εT4, where the heat radiation amount is Q1, the infrared emissivity is ε, and the temperature is T. The heat radiation amount Q can be controlled by changing the infrared radiation emissivity ε. In addition, the infrared emissivity ε(T) of a superconductor is determined by the temperature T as shown in Figure 2.
It is determined by , and changes significantly especially near the superconducting transition temperature Tc. In other words, when the temperature of the superconductor is lower than the superconducting transition temperature Te and it is in a superconducting state, the infrared emissivity ε(T) is small and the amount of radiated heat is small. , infrared emissivity ε(T
) becomes larger, and the amount of radiant heat also increases.

Therefore, when the temperature of the base plate 11 rises and heat is conducted to the heat sink 13, the amount of heat dissipated is small (,'l'c) until the temperature of the heat sink 13 reaches the superconducting transition temperature Te.
As the temperature becomes higher, n gradually increases. Then, when the pace plate 11 is cooled by the heat sink 13,
The heat sink 13 returns to the superconducting state again, and the base plate 1
It becomes difficult to dissipate heat from step 1. Therefore, the temperature of the pace plate 11 will be automatically controlled.

〔Effect of the invention〕

As explained above, according to the present invention, the heat sink made of a superconducting material is brought into close contact with the heat dissipated member of the artificial satellite, so that when the temperature of the heat sink rises above the superconducting transition temperature due to the heat conducted from the heat dissipation plate, , the amount of heat radiation increases and the amount of heat radiation increases, and when the temperature of the heat radiated member decreases, the amount of heat radiation of the heat sink also decreases, so the temperature of the heat radiated member can be automatically [controlled]. . Therefore, automatic temperature control can be realized with only the heat sink as a component, and a light heat sink can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a side cross-sectional view showing a heatsink according to the present invention, Fig. 2 is a graph showing the temperature dependence of infrared emissivity in a superconductor, and Figs. 3 (a) and (b) are graphs showing a conventional thermal louver. In the figures, (a) is a perspective view, and (b) is a side sectional view. 11... Base plate, 13... Heat sink.

Claims (1)

[Claims] A heat sink characterized by having a heat sink made of a superconducting material closely attached to a heat-dissipating member of an artificial satellite.