RU2328842C1 - Cabinet for radioelectronic equipment - Google Patents

Abstract

FIELD: electric engineering; radio-electronic equipment; cooling devices.

SUBSTANCE: casing of cabinet is separated by horizontal partitions into floors, on which demountable electric units with thermally loaded elements are installed. On the side wall of casing from the external side absorption-diffusion refrigerator machine is attached, which consists of evaporator, condenser, reflux cooler, absorber, generator. In interfloor partitions there are channels arranged, where evaporating sections of thermal pipes are installed. Condensation sections of thermal pipes are fixed with the help of split joints on the internal side of cabinet casing wall and are thermally connected to evaporator 6 of absorption-diffusion refrigerator machine. Evaporator is installed in heat insulated unit, which is fixed on internal side of cabinet wall with the help of split joints.

EFFECT: increase of cabinet maintainability without damage of its casing heat insulation.

6 dwg

Description

The invention relates to devices for electronic equipment, in particular to devices for cooling electronic equipment (CEA).

Known electronic unit with a cooling system based on a gas refrigeration machine [A.S. USSR N 488046, MKI F25B 9/00, 1974]. The cooling system allows for heat removal from the elements at a level lower than the temperature of the cooling medium, however, its operation is uneconomical (low efficiency of the gas refrigeration cycle), and the electric motor interferes with the operation of the REA.

Known cabinet for CEA [A.S. USSR N 651510, MKI N05K 7/20, 1979], adopted for the prototype, comprising a housing divided by horizontal partitions into floors, which are removable electrical units with heat-loaded elements, and a cooling system based on an absorption-diffusion refrigeration machine (ADXM), including a transfer thermosyphon with a source of thermal energy and an evaporator.

The source of thermal energy ADXM are REA fuel elements, such as semiconductors. The operation of the ADXM does not adversely affect the operation of the CEA, and the thermal coefficient of the ADXM is 3 ... 5 times higher than that of a gas refrigeration machine.

However, the prototype has a number of significant disadvantages.

Installation of the ADXM evaporator inside the CEA cabinet reduces its usable volume and requires sealing the evaporator inlet to the cabinet. In the manufacture of the evaporator, an environmentally harmful galvanizing operation must be carried out to apply an anti-corrosion coating.

In addition, the CEA operating mode is unstable, which causes an unstable supply of heat to the ADCM and, as a result, the inability to provide a stable temperature inside the cabinet.

The objective of the invention is to provide the necessary temperature conditions for the operation of CEA elements and to improve the maintainability of the cabinet for CEA in terms of replacing a failed ADXM without destroying the insulation of the cabinet.

The problem is achieved due to the fact that in a known cabinet for electronic equipment, comprising a housing divided by horizontal partitions into floors, on which removable electrical units with heat-loaded elements are placed, and a cooling system based on an absorption-diffusion refrigerating machine, according to the invention in interfloor partitions channels are made in which the evaporative sections of the heat pipes are installed, and the condensation sections of the heat pipes are fixed using detachable joints minutes on the inner wall of the enclosure and are thermally coupled to the evaporator diffusion absorption-refrigerating machine which is disposed in heat-insulated block, the block with the evaporator is fixed to the outside of the cabinet walls by means of plug connections.

The presence of these detachable joints increases the maintainability of the cabinet for CEA, since it makes it possible to replace a failed ADXM without destroying the insulation of the cabinet

The location of the ADXM evaporator in a special heat-insulated block prevents thermal effects of the environment, i.e. almost all of the produced cold is used to provide thermal conditions for REA elements.

The invention is illustrated by drawings.

Figure 1 shows a General view of the cabinet for electronic equipment.

Figure 2 presents the cabinet for CEA (front view) with ADXM on the side wall.

Figure 3 shows the cabinet for CEA (side view).

Figure 4 - ADXM evaporator in a thermally insulated block.

Figure 5 is a section aa of the ADXM evaporator.

Figure 6 shows the mounting diagram of the ADXM evaporator.

The cabinet for CEA contains a housing 1, separated by horizontal partitions 2 in layers on floors 3. On the floors there are removable electrical units 4. On the side wall 5 of the housing 1 is fixed using detachable connections ADXM, containing an evaporator 6, a condenser 7, a reflux condenser 8, an absorber 9, the tank of the absorber 10 and the generator 11, covered with a heat-insulating casing. In the channels of the interfloor partitions, the evaporative sections 12 of the heat pipe (TT) are located. The condensation sections 13 of the heat pipe extend along the side wall 5 of the cabinet from the inside. The condensation sections 13 TT are fixed to the side wall 5 of the cabinet in the zone 14 of the ADXM evaporator location. The lower the floor, the longer the condensation section 13 TT. The ADXM evaporator is made in the form of a three-stream coil-shaped heat exchanger and is located in a vertical plane. The evaporator contains 3 channels - the actual evaporator 15, internal 16 (the channel of the cleaned gas mixture) and the channel of liquid ammonia 17. The evaporator is completely located in a sealed heat-insulating block 18. The outer walls of the block are made of plastic, and the wall 19 in contact with the side wall of the cabinet is made made of highly conductive material such as aluminum. The evaporator 15 itself is fixed to the wall 19 by clamps 20. In the contact gap 21 there is a heat-conducting paste or a compressed highly porous cellular material with high structural thermal conductivity (copper) impregnated with a heat-conducting paste, for example, KPT-8.

Consider the operation of the cabinet for CEA on a specific example. As ADXM, the ASh-160 unit manufactured by the Vasilkovsky Refrigerator Plant is used. The heat carrier TT is water, the body of the TT is made of stainless steel.

During the operation of CEA elements, the source of thermal power of the ADXM generator also works. In this case, the implementation of the refrigeration cycle is carried out. Ammonia is mainly evaporated from the water-ammonia mixture, which enters the reflux condenser 8, and a weak (purified from ammonia) solution is fed to the inlet of the absorber 9. In the reflux condenser 8, water vapor is separated and the purified ammonia vapor enters the condenser 7, where it liquefies and flows down the liquid channel ammonia 17 to the input of the evaporator 15 itself. During the flow, liquid ammonia is supercooled. In the annulus of the evaporator, liquid ammonia evaporates into the vapor-gas medium (ASG) at a low partial pressure (0.9 ... 1.0 bar). In this case, the temperature is minus (27 ... 30 ° C). Due to the higher density, the PGS saturated with ammonia is lowered into the tank of the absorber 10 and then goes to the inlet of the coil absorber 9. In the absorber, countercurrent absorption of ammonia vapor from the PGS takes place with a weak aqueous ammonia solution. The PGS purified from ammonia vapors through the internal channel 16 enters the inlet of the evaporator, and the ammonia-rich aqueous ammonia solution enters the generator inlet, and the cycle repeats.

When the purified ASG moves along the internal channel 16, its subcooling is carried out. Hypothermia of ammonia in the channel of liquid ammonia 17 and ASG in the internal channel 16 leads to a decrease in the level of cooling temperatures and an increase in refrigeration power.

During the operation of CEA elements, thermal energy is released, which is transferred to the air or directly to the partition walls 2. In this case, in the evaporative sections of the 12 CTs, the generation of coolant - water vapor occurs. Water vapor enters the condensation sections 13 TT, where they are liquefied with the removal of heat of vaporization to the evaporator.

Due to the operation of the TT in the evaporation-condensation cycle, a high isothermality of the REA elements is achieved.

Thus, high operational characteristics of the cabinet for CEA are provided.

Conducted research [Vasiliev OB Optimization of the operating modes of devices for various functional purposes with ADXM: Dis. Cand. tech. Sciences: 05.04.03. - Odessa, 1998] showed that the ADHM type ASh-160 provides a temperature level minus (18 ... 20 ° C) with a thermal load on the low-temperature (initial) part of the evaporator 10 ... 12 W and at the same time the temperature 0 ... 5 ° С at a thermal load on the middle section 12 ... 14 W.

In these tests, in the contactless gaps 21 was a compressed copper highly porous cellular material impregnated with KPT-8 paste. The value of the effective thermal conductivity of the gap was 8.3 ... 8.5 W / (mK). This is especially important because the contact of the flat surface of the wall 19 with the actual evaporator 15, made in the form of a tube with a diameter of 32 mm, was ensured.

The maintainability of the cabinet for CEA is enhanced by introducing detachable joints into the design for mounting a heat-insulated unit with an ADXM evaporator on the outside of the cabinet wall. This allows you to replace ADXM without destroying the insulation of the cabinet for CEA.

Claims (1)

Cabinet for electronic equipment, comprising a housing divided by horizontal partitions into floors, on which removable electrical units with heat-loaded elements are located, and a cooling system based on an absorption-diffusion refrigeration machine, characterized in that channels are installed in the interfloor partitions, in which evaporative sections are installed heat pipes, and the condensation sections of the heat pipes are fixed using detachable connections on the inner side of the cabinet wall and have a thermal connection with and an absorber of an absorption-diffusion refrigeration machine, which is located in a sealed heat-insulated unit, the unit with an evaporator mounted on the outside of the cabinet wall using detachable connections.

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