SU326906A1 - LOW-TEMPERATURE HINGE FOR NUCLEAR RESEARCH - Google Patents

Description

The invention relates to nuclear technology, in particular to low temperature loops for nuclear research.

In low-temperature loops for nuclear research, the gaseous coolant (helium) artificially circulating in a closed circuit outside the irradiation zone, in a heat exchanger, is cooled by a liquid refrigerant, then in the irradiation zone, in the working chamber of the cryostat channel, cools the chamber walls and the sample and sensor .

In the known low-temperature loops for nuclear research, the channel-cryostat and the heat exchanger are two separate assemblies connected by pipelines, as a result of which the coolant travels a large distance from the heat exchanger to the chamber and heats up considerably.

In addition, in these installations, the coolant enters the chamber from one end and before the sample is blown off, it is heated by the heat of radiative heating of that part of the chamber, and those dividers of the sensor placed in it, which are in the path of the coolant to the sample. This is especially felt with high radiation power and a bulky sensor.

coolant flow rate, and coolant consumption constant.

In the proposed installation, these drawbacks are eliminated due to the fact that the heat exchanger is located in the vacuum jacket of the cryostat channel at a minimum distance from the chamber, determined by the thickness of the required radiation protection. An opening is provided for introducing the coolant into the chamber.

at the center of the core versus the location of the sample. To withdraw the coolant, there are two holes located at the ends of the working chamber on either side of the inlet. The refrigerant supply system is equipped with devices for controlling and controlling its consumption.

The drawing shows a schematic diagram of a low-temperature loop for nuclear research.

The cryostat channel of the low-temperature loop is placed in the reactor tank. B 1, which is the vacuum jacket of the cryostat channel, is equipped with a working chamber 2 and a heat exchanger 3. The working chamber is located in

the irradiated part of the cryostat channel, and the heat exchanger - in the part protected from irradiation by the radiation protection unit 4. Channel 5 is provided for loading sample 6 and sensor 7 into the working chamber.

penetration of radiation into the reactor hall through the loading channel. To supply the circulating tenon carrier into the working chamber, there is a pipe 9 connected to it at the level of the center of the core, and to the heat exchanger in its coldest part, at the point of supplying the liquid refrigerant. A pipeline 10 for withdrawing the coolant from the working chamber is connected to it by two openings at the upper and lower ends of the working chamber, and to the heat exchanger at the point of the corresponding temperature level in order to use the residual cold of the return flow of the coolant. The pipeline 10 serves as a shield for the pipeline 9 from thermal radiation.

The system of artificial circulation of the gaseous coolant consists of a compressor / V and a gas tank 12, which are connected to the cryostat channel by pipe 13. The valve 14 serves to control the flow of the coolant, to control it - the flow meter 15.

The refrigerant supply system consists of a liquid refrigerant vessel 16 connected to a cryostat-channel overflow 17, and a pump 18 for pumping refrigerant vapor connected to a cryostat-channel 19. The valve 20 serves to adjust the flow rate of the refrigerant, and the flow meter 21 to control it. The overflow 22 is provided for filling the vessel 16 with a liquid refrigerant.

The loop works as follows.

The sample with the sensor is suspended on the plug 8 and is lowered through the loading channel 5 into the working chamber 2 so that the center of the sample is at the level of the input of the coolant into the chamber. With this arrangement, the sample is cooled with a fresh stream of circulating coolant and is irradiated most intensely. After that, the internal system of the loop is pumped out, and coolant is fed into it from the gas-holder 12. The vessel 16 is filled with liquid refrigerant. Then, the compressor // and the pump 18 are turned on, as a result of which the coolant circulates and the liquid coolant flows. After that, with the help of the valve 14, the required flow rate of the coolant is established, and by changing the flow rate of the refrigerant using the valve, the 20-desired sample temperature.

Smooth cooling or heating of the sample is provided by varying the flow rate of the coolant and coolant alternately or simultaneously.

The described low-temperature loop makes it possible to lower the limiting temperature of cooling the sample by 5–40 ° C, depending on the experimental conditions, and smoothly adjust the temperature of the sample from low to room temperature.

Subject invention

Claims (2)

1. A thermotechnical loop for nuclear research, containing a cryostat channel with a working chamber for the sample under investigation in the reactor radiation zone, a heat exchanger with a liquid refrigerant outside the radiation zone, an artificial circulating coolant system and a refrigerant supply system, so as to increase smoothness of temperature control of the sample and its cooling efficiency, the heat exchanger is placed in the cryostat channel directly behind the radiation protection units, and the working chamber is provided with openings; one to introduce the coolant at the level of the center of the sample and two, one at the upper and lower ends of it, for the withdrawal of the coolant. 2. Pizcotemnerur 1a of the loop according to claim 1, characterized in that the refrigerant circulation system is equipped with devices for controlling and controlling its flow rate.