Superconducting magnet cold energy recovery system

Abstract

The invention relates to the technical field of superconducting magnets, in particular to a superconducting magnet cold energy recovery system. A superconducting magnet cold energy recovery system comprises a shell which is a Dewar container, and is characterized in that a cold shield is arranged in the shell, and a steel pipe disc is arranged on the outer side of the cold shield; a cold shield tank is arranged in the cold shield, one side of the top of the cold shield tank is connected with a liquid helium inlet, and the other side of the top of the cold shield tank is connected with a cooling system outlet; a superconducting coil is arranged in the cold shield tank, and the two ends of the superconducting coil are connected with current wires respectively. Compared with the prior art, the superconducting magnet cold energy recovery system provided by the invention has the advantages that helium entering the current lead is pre-cooled through heat exchange between the low-temperature helium inlet of the current lead and the low-temperature helium outlet of the superconducting coil, so that low-temperature helium cold energy from the superconducting coil is recovered.

Description

Technical Field

[0001] The invention relates to the technical field of superconducting magnets, in particular to a superconducting magnet cold energy recovery system. Background Art

[0002] The use of liquid helium in superconducting magnets is of great significance, but its scarcity is also an issue that cannot be ignored.

[0003] Liquid helium is extracted from natural gas, mainly in areas where there are helium reserves. The major helium producers in the world include the United States, Qatar, Russia and Algeria. Since helium is a very light gas that escapes in the Earth's atmosphere, its resources are limited and non-renewable.

[0004] Natural helium resources are limited, and the process of collecting and separating helium is expensive. Many helium fields are gradually depleting, making the discovery and development of new resources more difficult. Therefore, the reserves of helium are limited.

[0005] Liquid helium is expensive to produce and transport, especially in the process of cooling helium to its liquefaction point (-269°C) to make it liquid. This makes liquid helium relatively expensive.

[0006] As technology advances, especially in the fields of medical imaging (such as MRI), particle accelerators and high-energy physics experiments, the demand for superconducting magnets increases, and the demand for liquid helium also increases.

[0007] Superconducting magnets need to be kept at very low temperatures when working to maintain the superconducting state. The low temperature of liquid helium (close to absolute zero) allows superconductors to operate without consuming energy. This temperature is critical to the performance of superconducting magnets, so liquid helium becomes a key coolant to achieve this process.

[0008] Due to the insufficient supply of liquid helium, the operating and maintenance costs of superconducting magnets may rise significantly. The shortage of liquid helium may limit the operation of certain high-tech equipment and experiments, affecting the availability of scientific research and medical equipment. The shortage also prompts researchers to explore alternative coolants and more efficient technologies for using liquid helium to reduce dependence on liquid helium.

[0009] In response to the scarcity of liquid helium, the scientific and industrial communities are taking some measures: Many laboratories and equipment have adopted liquid helium recovery systems to reduce waste. Other coolants such as liquid nitrogen, although they cannot completely replace liquid helium, may be helpful in some applications. Scientists are also studying alternative sources of helium, such as extracting helium-3 from lunar soil. The scarcity of liquid helium is a complex challenge, but its impact on scientific and industrial applications can be partially alleviated through technological innovation and resource management. Summary of the invention

[0010] In order to overcome the deficiencies of the prior art, the present invention provides a superconducting magnet cold energy recovery system, which reduces the amount of helium used by recovering liquid helium to cool the superconducting magnet system itself, thereby achieving the purpose of saving helium resources.

[0011] To achieve the above purpose, a superconducting magnet cold energy recovery system is designed, comprising a shell, wherein the shell is a Dewar container, and is characterized in that: a cold shield is provided inside the shell, and a steel pipe coil is provided outside the cold shield; a cold shield tank is provided inside the cold shield, one side located at the top of the cold shield tank is connected to the liquid helium inlet, and the other side of the top of the cold shield tank is connected to the cooling system outlet; a superconducting coil is provided inside the cold shield tank, and both ends of the superconducting coil are respectively connected to current wires.

[0012] The current conductors at both ends of the superconducting coil respectively penetrate the cold shield tank and the top of the cold shield, and are located outside the shell and connected to an external power source.

[0013] The connection between the current conductor and the cold shield is connected via a thermal connection component, and the connection between the current conductor and the shell is connected via a sealing component.

[0014] The current wire is a high-temperature superconducting current lead.

[0015] The cold shield tank is 4.2K, and at least four channels are arranged on the top of the cold shield tank, the first channel is connected to the liquid helium inlet, the second channel is connected to the first helium outlet, the third channel is connected to the cooling system outlet, the second channel and the fourth channel are provided with current conductors, and the top of the third channel is interconnected with the middle of the second channel and the third channel.

[0016] One end of the cooling system outlet is located outside the shell, and one end of the cooling system outlet is connected to the first helium inlet, and the other end of the cooling system outlet is connected to the third channel of the cold shield tank; a plurality of blocking plates are evenly arranged in the cooling system outlet; the blocking plates have a smooth and reflective surface, and gaps are provided on the wall of the blocking plates.

[0017] A heat exchange wall is arranged on the pipeline between the cooling system outlet and the first helium inlet, and a combination of one or more structures including protrusions, corrugated surfaces and fins is arranged on the wall surface of the heat exchange wall.

[0018] The steel pipe coil is a 304 stainless steel pipe wound around the outside of the cold screen, one end of the steel pipe coil is a second helium inlet, and the other end of the steel pipe coil is a second helium outlet; the second helium inlet and the second helium outlet are respectively located on the outside of the shell.

[0019] The shell is 300K.

[0020] The cold shield is 50K.

[0021] Compared with the prior art, the present invention provides a superconducting magnet cold energy recovery system, which precools the helium entering the current lead by performing heat exchange between the low-temperature helium inlet of the current lead and the low-temperature helium outlet of the superconducting coil, so as to recover the cold energy of the low-temperature helium coming out of the superconducting coil. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the structure of the present invention.

[0023] Figure 2 It is a schematic diagram of the enlarged structure of the cooling system outlet in the present invention.

[0024] See also Figure 1 , Figure 2 , 1 is a shell, 2 is a cold shield, 3 is a cold shield tank, 3-1 is a first channel, 3-2 is a second channel, 3-3 is a third channel, 3-4 is a fourth channel, 4 is a superconducting coil, 5 is a current wire, 6 is a first helium outlet, 7 is a first helium inlet, 8 is a cooling system outlet, 9 is a blocking plate, 10 is a thermal connection assembly, 11 is a sealing assembly, 12 is a liquid helium inlet, 13 is a second helium inlet, 14 is a second helium outlet, and 15 is a steel pipe coil. DETAILED DESCRIPTION

[0025] The present invention will be further described below with reference to the accompanying drawings.

[0026] like Figure 1 , Figure 2 As shown, a cold shield 2 is provided inside the shell 1, and a steel pipe coil 15 is provided on the outside of the cold shield 2; a cold shield tank 3 is provided inside the cold shield 2, one side located at the top of the cold shield tank 3 is connected to a liquid helium inlet 12, and the other side of the top of the cold shield tank 3 is connected to a cooling system outlet 8; a superconducting coil 4 is provided inside the cold shield tank 3, and both ends of the superconducting coil 4 are respectively connected to current conductors 5.

[0027] The current conductors 5 at both ends of the superconducting coil 4 respectively penetrate the top of the cold shield tank 3 and the cold shield 2 and are located outside the shell 1 to be connected to an external power source.

[0028] The connection between the current conductor 5 and the cold shield 2 is connected via a thermal connection assembly 10 , and the connection between the current conductor 5 and the housing 1 is connected via a sealing assembly 11 .

[0029] The current wire 5 is a high temperature superconducting current lead.

[0030] The cold shield tank 3 is 4.2K, and at least four channels are arranged at the top of the cold shield tank 3. The first channel 3-1 is connected to the liquid helium inlet 12, the second channel 3-2 is connected to the first helium outlet 6, and the third channel 3-3 is connected to the cooling system outlet 8. Current conductors 5 are arranged in the second channel 3-2 and the fourth channel 3-4, and the top of the third channel 3-3 is interconnected with the middle of the second channel 3-2 and the third channel 3-3.

[0031] One end of the cooling system outlet 8 is located outside the shell 1, and one end of the cooling system outlet 8 is connected to the first helium inlet 7, and the other end of the cooling system outlet 8 is connected to the third channel 3-3 of the cold shield tank 3; a plurality of blocking plates 9 are evenly arranged in the cooling system outlet 8; the blocking plates 9 have a smooth and reflective surface, and gaps are provided on the wall of the blocking plates 9.

[0032] A heat exchange wall is provided on the pipeline between the cooling system outlet 8 and the first helium inlet 7. A combination of one or more structures including protrusions, corrugated surfaces and fins is provided on the wall surface of the heat exchange wall.

[0033] The steel pipe coil 15 is a 304 stainless steel pipe wound around the outside of the cold screen 2 , one end of the steel pipe coil 15 is a second helium inlet 13 , and the other end of the steel pipe coil 15 is a second helium outlet 14 ; the second helium inlet 13 and the second helium outlet 14 are respectively located on the outside of the shell 1 .

[0034] Shell 1 is 300K.

[0035] Cold Screen 2 is 50K.

[0036] The 50K cold shield cooling system in the Dewar container (i.e., the shell 1) is a 304 stainless steel pipe coil 15 wound around the 50K cold shield 2. Low-temperature helium gas flows through the steel pipe coil 15 to cool the 50K cold shield 2.

[0037] Liquid helium is poured into the cold shield tank 3 to cool the superconducting coil 4 to reduce the temperature of the superconducting coil 4 to a superconducting state. A plurality of baffles 9 are installed in the pipeline of the cooling system outlet 8 to reduce the convection heat transfer and radiation heat transfer of the helium in the cooling system outlet 8.

[0038] The current lead 5 is divided into two sections, and the upper end of the current lead 5 is outside the Dewar container (i.e., the shell 1) and connected to an external power supply. The lower section of the current lead 5 is connected to the cold shield 2 through a thermal connection component 10, and the upper section of the current lead 5 is connected to the outer shell 1 through a sealing component 11. The current lead 5 is a high-temperature superconducting current lead, and the lower end of the current lead 5 is connected to the superconducting wire of the superconducting coil 4.

[0039] The cold energy recovery system is a heat exchange between the low-temperature helium at the cooling system outlet 8 of the superconducting coil 4 in the Dewar container (i.e., the shell 1) and the cooling system inlet (i.e., the first helium inlet 7) of the current lead 5. The heat exchange wall of the pipe at the cooling system outlet 8 and the cooling system inlet (i.e., the first helium inlet 7) has many protrusions and corrugated surfaces, which has achieved the purpose of enhancing heat exchange. Thus, the purpose of pre-cooling the helium at the cooling system inlet (i.e., the first helium inlet 7) of the current lead 5 is achieved, thereby reducing the amount of helium used.

Claims

1. A superconducting magnet cold energy recovery system, comprising a housing, wherein the housing (1) is a Dewar container, characterized in that: A cold shield (2) is provided inside the shell (1), and a steel pipe coil (15) is provided outside the cold shield (2); a cold shield tank (3) is provided inside the cold shield (2), one side located at the top of the cold shield tank (3) is connected to a liquid helium inlet (12), and the other side of the top of the cold shield tank (3) is connected to a cooling system outlet (8); a superconducting coil (4) is provided inside the cold shield tank (3), and both ends of the superconducting coil (4) are respectively connected to current conductors (5).

2. A superconducting magnet cold energy recovery system according to claim 1, characterized in that: The current conductors (5) at both ends of the superconducting coil (4) respectively penetrate the top of the cold shield tank (3) and the cold shield (2), and are located outside the shell (1) and connected to an external power source.

3. A superconducting magnet cold energy recovery system according to claim 1 or 2, characterized in that: The connection point between the current conductor (5) and the cold shield (2) is connected via a thermal connection component (10), and the connection point between the current conductor (5) and the housing (1) is connected via a sealing component (11).

4. A superconducting magnet cold energy recovery system according to claim 1 or 2, characterized in that: The current wire (5) is a high-temperature superconducting current lead.

5. The superconducting magnet cold energy recovery system according to claim 1, characterized in that: The cold shield tank (3) is 4.2K, and at least four channels are provided at the top of the cold shield tank (3), the first channel (3-1) is connected to the liquid helium inlet (12), the second channel (3-2) is connected to the first helium outlet (6), and the third channel (3-3) is connected to the cooling system outlet (8), the second channel (3-2) and the fourth channel (3-4) are provided with current conductors (5), and the top of the third channel (3-3) is interconnected with the middle of the second channel (3-2) and the third channel (3-3).

6. A superconducting magnet cold energy recovery system according to claim 1 or 5, characterized in that: One end of the cooling system outlet (8) is located outside the shell (1), and one end of the cooling system outlet (8) is connected to the first helium inlet (7), and the other end of the cooling system outlet (8) is connected to the third channel (3-3) of the cold shield tank (3); a plurality of blocking plates (9) are evenly arranged in the cooling system outlet (8); the blocking plates (9) have a smooth and reflective surface, and a slit is provided on the wall of the blocking plates (9).

7. A superconducting magnet cold energy recovery system according to claim 1 or 5, characterized in that: A heat exchange wall is provided on the pipe between the cooling system outlet (8) and the first helium inlet (7), and a combination of one or more structures including protrusions, corrugated surfaces and fins is provided on the wall surface of the heat exchange wall.

8. The superconducting magnet cold energy recovery system according to claim 1, characterized in that: The steel pipe coil (15) is a 304 stainless steel pipe wound around the outside of the cold screen (2); one end of the steel pipe coil (15) is a second helium inlet (13), and the other end of the steel pipe coil (15) is a second helium outlet (14); the second helium inlet (13) and the second helium outlet (14) are respectively located on the outside of the shell (1).

9. A superconducting magnet cold energy recovery system according to claim 1, characterized in that: The shell (1) is 300K.

10. The superconducting magnet cold energy recovery system according to claim 1, characterized in that: The cold shield (2) is 50K.

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