RU170671U1 - Combined deep-cooling system for photodetectors - Google Patents

Abstract

The utility model relates to the field of cryogenic technology and cryogenic refrigerators operating on the reverse Stirling cycle, can be used to cool infrared radiation receivers, lasers, elements of electronic equipment and other objects performing research in space. A combined system of deep cooling of photodetector devices ) contains two microcryogenic systems (ISS) according to the Sterling cycle with a cooling capacity of 10 W each, heat pipes from the ISS to a cryostat, a cryostat with melting I am a substance fixed through heat-insulating sleeves with a sealed casing, copper cold pipes from the cryostat to photodetectors, while the two ISS cyclically work alternately. Argon was used as a cryogenic substance. The total resource of active work of the equipment of the deep cooling system of photodetector devices was prolonged for about 7-10 years, while the mechanical (vibrational) and electromagnetic effects created by the ISS during the operation of the spacecraft equipment were reduced. 1 s.p. f-ly, fig. one

Description

The utility model relates to the field of cryogenic technology, cryogenic refrigerators operating in the reverse Sterling cycle, and can be used to cool infrared radiation receivers, lasers, electronic components and other objects performing research in space.

Known combined deep cooling systems for photodetectors based on cold accumulators on melting substances at nitrogen temperatures (see Formozov B.N., Aerospace photodetectors in the visible and infrared ranges. Textbook. Manual / SPb SUAI. St. Petersburg, 2002, p. . 91-94). Known systems have an insufficient resource of use, not more than 3-5 years.

The closest in technical level to the claimed utility model is a cryostatized deep cooling system of a photodetector (patent RU 2206027, MKI F25B 9/14).

This system of deep cooling of a photodetector (FPU) contains a Sterling cooler, a cold pipe with a solid-state television photoelectric converter located on it, a circulation heat exchange circuit and a two-valve bellows diaphragm pump with a reciprocating drive. A container with a melting cryogenic substance (cryostat) is mounted on a heat shield using low-conductive fiberglass supports and is insulated from the cooler using capillaries with a low value of thermal conductivity. The cryogenic liquid of the circulation heat exchange circuit has a triple point temperature significantly lower than the corresponding melting temperature of the melting cryogenic substance, and the normal boiling point is much higher than the triple point temperature of the melting cryogenic substance. A cold pipe with a solid-state television photoelectric converter is also mounted on a heat shield using low-conductive fiberglass supports and is insulated from a container with a melting cryogenic substance using capillaries made of a material with low thermal conductivity.

This device is selected as a prototype.

The disadvantages of the known device are the limited service life of 3 to 5 years and the often repeated frequency of turning on the engine of the microcryogenic system (ISS), during which the FPU cannot be used for its intended purpose due to electrical and vibration interference from the operating ISS electric motor.

The purpose of the utility model is to extend the service life to 7-10 years and reduce the frequency of operation of microcryogenic systems.

The goal is achieved due to the fact that heat pipes from the ISS to the cryostat, a cryostat with fusible material, fixed through heat-insulating sleeves with a sealed casing, and copper refrigerant pipes from the cryostat to the FPU are introduced into the combined FPU deep cooling system containing the first microcryogenic system according to the Sterling cycle the second microcryogenic system, and the refrigerating capacity of each ISS is 10 W, and the ISS are turned on cyclically and alternately.

An inert gas Argon (Ar) having a melting point of 83.8 K, which corresponds to minus 189.35 ° C, can be used as a cryogenic substance.

Utility model — a combined FPU deep cooling system is illustrated by the figure in FIG. 1, where:

1 - a container with a melting cryogenic substance (cryostat);

2 - the first microcryogenic system;

3 - diode heat pipes;

4 - copper cold lines;

5 - a complex of photodetectors;

6 - receiver;

7 - heat insulating bushings;

8 - sealed housing;

9 - depressurization valve;

10 - the second microcryogenic system;

11 - heat pipes - heat removal from the ISS.

The combined deep-cooling system of the photodetector contains a sealed enclosure 8, in which a system of cooled FPU 5 and a container with a melting substance (cryostat) 1 are installed, mounted inside the enclosure 8 with heat-insulating sleeves 7. A complex of two microcryogenic systems 2 and 10 based on gas cryogenic machines of the type Split-Stirling provides cooling of the cryostat 1 to the level of operating temperatures (83 ± 2) K through oxygen diode heat pipes 3. Heat is removed from the photodetector 5 to cryostat 1 without copper cold pipes 4. The entire system is placed in a sealed enclosure 8. On the enclosure 8 is a valve 9, designed to depressurize the product in space. The cryostat 1 is connected through the pipelines to the receiver 6, which serves to reduce the pressure in the cryostat 1 when the system is in the “warm” state and the heat-accumulating substance passes into the gaseous state, which allows for long interruptions in the operation of the spacecraft equipment. Heat removal from microcryogenic systems 2 and 10 during operation occurs through heat pipes 11 into the system for ensuring the thermal regime of the spacecraft (SOTR KA).

The combined deep cooling system of photodetectors works as follows.

After the spacecraft is put into orbit, to evacuate the internal volume of the system, the depressurization valve 9 opens and the system for providing thermal control of the SOTR spacecraft begins to work, creating the operating temperature of the complex from two ISS 2 and 10 in the temperature range from minus 20 ° С to plus 35 ° С . During ground operation and at the stage of launching the spacecraft into orbit, the receiver 6 and the cryostat 1 communicating with it are filled with a heat-accumulating substance in a gaseous state, for example, Argon. The complex of two ISS 2 and 10 provides cooling of the cryostat 1 to the crystallization temperature of the heat-accumulating substance. After the crystallization process is completed, the first and second ISS 2 and 10 are turned off. Further temperature maintenance for cooling the photodetectors 5 is carried out due to the phase transition of the heat-accumulating substance from the solid phase to the liquid phase (melting). After all the substance goes into the liquid phase, one of the two ISS 2 or 10 is turned on again. Maintaining stable temperature values of photodetectors in a given temperature range is ensured by the alternate cyclic operation of the ISS complex. The ISS operation cycle is selected so that the period of active operation of the spacecraft equipment coincides with the interruption in the work of the ISS, which eliminates the mechanical (vibrational) and electromagnetic effects created by the operation of the ISS on the operation of the spacecraft equipment.

The structure of the product includes two microcryogenic systems with a cooling capacity of about 10 W each, and each of them has a life of about 10,000 hours. Cyclical alternate operation of two ISS significantly reduces the effect of the ISS operation on the spacecraft due to faster cooling of the cryostat, which allows providing a common active resource operation of spacecraft equipment for about 7-10 years.

Claims (2)

1. The combined deep cooling system of photodetectors, comprising a sealed enclosure, a first microcryogenic system according to the Sterling cycle, a cryostat with a melting substance, fixed through heat-insulating sleeves inside the sealed enclosure, copper cold pipes connecting the cryostat and photodetectors, characterized in that a second microcryogenic system is introduced moreover, the first and second mentioned systems are connected through heat pipes to a cryostat with the possibility of alternating cyclic connection each system, wherein the refrigeration capacity of each microcryogenic system is 10 watts. 2. The combined deep cooling system of photodetectors according to claim 1, characterized in that Argon is used as a cryogenic substance.

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