CN111879027A - A flexible pulse tube refrigerator - Google Patents

Abstract

The invention discloses a flexible pulse tube refrigerator, which sequentially comprises a compressor, a heat exchanger at the hot end of a regenerator, a heat exchanger, a heat exchanger at a cold end, a pulse tube and a heat exchanger at the hot end of the pulse tube, and is characterized in that , the whole of the vessel or the vessel near the hot end is a flexible vessel, and the flexible vessel is realized by a corrugated tube. The advantage of the invention is that the structure is simpler and more compact, and a satisfactory phase modulation effect can be achieved as long as the rigidity of the bellows is controlled.

Description

A flexible pulse tube refrigerator

technical field

The invention relates to a flexible pulse tube refrigerator, which belongs to the technical field of pulse tube refrigerators.

Background technique

In the 1960s, Gifford and Longsworth in the United States found that when there are alternating pressure waves in a hollow tube, the closed end of the tube will heat up, and a temperature gradient will be formed along the axial direction, and then a regenerator will be installed. And the laminar fluidization element, low temperature can be obtained in the pulse tube close to the compressor outlet, which is the prototype of the pulse tube refrigerator. With the advancement of research, it has been found that optimizing heat exchange equipment can effectively reduce the minimum cooling temperature of pulse tube refrigerators. Therefore, it includes compressors, main coolers, regenerators, subcoolers, pulse tubes, and laminar fluidization elements. The basic type of vasculature comes out, as shown in Figure 1. However, the basic pulse tube lacks the phase modulation ability, resulting in low refrigeration efficiency, so various phase modulation structures have appeared one after another. Commonly used phase modulation mechanisms include small hole type, multi-directional air intake type, and inertial tube type, as shown in Figure 2. In order to further improve the phase modulation capability, a room temperature phase modulation pulse tube refrigerator has recently appeared. As shown in Figure 3, a displacement piston is connected to the hot end of the pulse tube. The displacement piston can be an active drive type to actively adjust and The phase of the compressor can also be a passive free piston type, and the rear connecting spring can adjust the phase with the compressor by adjusting the spring stiffness. Obviously, this phase modulation method increases the complexity of the machine, reduces the reliability of the machine, and increases the vibration.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is how to improve the technical reliability of the pulse tube refrigerator.

In order to solve the above technical problems, the technical solution of the present invention is to provide a flexible pulse tube refrigerator, which sequentially includes a compressor, a heat exchanger at the hot end of a regenerator, a regenerator, a heat exchanger at the cold end, a pulse tube and a pulse tube. The tube hot end heat exchanger is characterized in that, the whole vessel or the vessel near the hot end is a flexible vessel, and the flexible vessel is realized by a corrugated tube.

Preferably, an inertial tube and a gas reservoir are sequentially connected behind the pulse tube hot end heat exchanger.

Preferably, the gas storage is a flexible gas storage with variable volume, and the flexible gas storage is realized by a bellows.

Preferably, there are parallel channels in the vessel, the parallel channels are made of polytetrafluoroethylene/nylon or low thermal conductivity material using 3D printing or a plate, and the thickness of the channel sheets constituting the parallel channels ranges from 0.1mm to 0.5mm, and both ends of the parallel channel are fixed by rings.

Preferably, all of the flexible pulse tube refrigerators can be applied to GM type pulse tube refrigerators.

The advantage of the invention is that the structure is simpler and more compact, and a satisfactory phase modulation effect can be achieved as long as the rigidity of the bellows is controlled.

Description of drawings

Figure 1 is a schematic diagram of a basic pulse tube refrigerator; wherein, 1-compressor, 2-regenerator hot end heat exchanger, 3-regenerator, 4-cold end heat exchanger, 5-pulse tube, 6- Pulse tube hot end heat exchanger;

Fig. 2 is the schematic diagram of inertia tube type pulse tube refrigerator;

Figure 3 is a schematic diagram of a displacement piston type pulse tube refrigerator; wherein, compressor, 2-regenerator hot end heat exchanger, 3-regenerator, 4-cold end heat exchanger, 5-pulse tube, 6-pulse Tube hot end heat exchanger, 7-displacer: here is the free room temperature piston;

Figure 4 is a schematic diagram of a partial flexible pulse tube type pulse tube refrigerator; wherein, 1-compressor, 2-regenerator hot end heat exchanger, 3-regenerator, 4-cold end heat exchanger, 5-pulse tube : The hot end here is bellows, 6-pulse tube hot end heat exchanger, 7-displacer: here is inertia tube, 8-gas reservoir;

Figure 5 is a schematic diagram of all flexible pulse tube type pulse tube refrigerators; wherein, 1-compressor, 2-regenerator hot end heat exchanger, 3-regenerator, 4-cold end heat exchanger, 5-pulse tube : The hot end here is bellows, 6-pulse tube hot end heat exchanger, 7-displacer: here is inertia tube, 8-gas reservoir;

Figure 6 is a schematic diagram of a flexible gas storage type pulse tube refrigerator; wherein, 1-compressor, 2-regenerator hot end heat exchanger, 3-regenerator, 4-cold end heat exchanger, 5-pulse tube: Here is the multi-channel bellows, 6-pulse tube hot end heat exchanger, 7-displacer: here is the inertial tube, 8-air storage: here the bellows is used to realize the flexible gas storage;

7 is a schematic diagram of a parallel channel pulse tube refrigerator; wherein, (a) is a schematic diagram of an axial front view of the pulse tube refrigerator, and (b) is a side view of a parallel channel pulse tube;

Fig. 8 is the fixed ring at both ends of the parallel channel in the structure shown in Fig. 7;

Fig. 9 is a schematic diagram of a flexible parallel channel pulse tube refrigerator; wherein, 1-compressor, 2-regenerator hot-end heat exchanger, 3-regenerator, 4-cold-end heat exchanger, 5-pulse tube, Here is the multi-channel bellows, 6-pulse tube hot end heat exchanger, 7-displacer: here is the inertia tube, 8-gas storage;

FIG. 10 is a schematic diagram of a GM type pulse tube refrigerator.

Detailed ways

In order to make the present invention more obvious and comprehensible, preferred embodiments are described in detail below with reference to the accompanying drawings.

Example 1

In this example, a new form of pulse tube refrigerator is called a flexible pulse tube refrigerator, as shown in Figures 4 and 5. Change the vessel 5 near the hot end to a bellows, or change the entire vessel 5 to a bellows to replace the function of the room temperature piston. When the vessel 5 is in the inflation stage, the bellows becomes longer, which is equivalent to the expansion of the displacement piston , in the deflation stage of the pulse tube 5, the bellows becomes shorter, which is equivalent to the compression of the displacement piston, thereby recovering the work. Obviously, the structure of the present invention is simpler and more compact, and as long as the rigidity of the bellows is controlled, a satisfactory phase modulation effect can be achieved. At the same time, the present invention can also be used without the inertial tube.

Example 2

Further, the present invention provides a flexible gas storage pulse tube refrigerator. The existing gas storages 8 are rigid containers with large volume, which is not conducive to space placement. The present invention proposes a flexible gas storage with variable volume, and the flexibility can be realized by bellows. As shown in Figure 6.

Example 3

In addition, in order to improve the degree of laminar fluidization in the pulse tube 5, for a pulse tube refrigerator with a large cooling capacity, when the diameter of the pulse tube is large, the present invention proposes a parallel channel type pulse tube refrigerator, as shown in FIG. 7 . . The parallel channel is made of polytetrafluoroethylene material and adopts 3D printing technology. The thickness of the sheet is preferably 0.1mm, or 0.5mm, and the two ends are fixed by rings, as shown in Figure 8. At the same time, the parallel channel type pulse tube refrigerator can also be combined with a flexible pulse tube and a gas reservoir, as shown in FIG. 9 .

The above inventions can all be used in the GM type pulse tube refrigerator, that is, the linear reciprocating compressor is replaced by a high and low pressure gas cylinder and a rotary valve.

Claims (6)

1. a flexible pulse tube refrigerator, comprising successively a compressor, a regenerator hot end heat exchanger, a regenerator, a cold end heat exchanger, a pulse tube and a pulse tube hot end heat exchanger, characterized in that the entire The vessel or vessel near the hot end portion is a flexible vessel, the flexible vessel being realized by a bellows. 2 . The flexible pulse tube refrigerator according to claim 1 , wherein an inertial tube and a gas reservoir are sequentially connected behind the pulse tube hot end heat exchanger. 3 . 3 . The flexible pulse tube refrigerator according to claim 2 , wherein the gas storage is a flexible gas storage with variable volume, and the flexible gas storage is realized by a bellows. 4 . 4 . The flexible pulse tube refrigerator according to claim 1 , wherein parallel channels are arranged in the pulse tube. 5 . 5 . The flexible pulse tube refrigerator according to claim 4 , wherein the parallel channel is made of polytetrafluoroethylene or nylon by 3D printing or a plate, and the thickness range of the channel sheet constituting the parallel channel is 5 . It is 0.1mm-0.5mm, and both ends of the parallel channel are fixed by circular rings. 6 . The flexible pulse tube refrigerator according to claim 1 , wherein the flexible pulse tube refrigerator can be applied to a GM type pulse tube refrigerator. 7 .

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