A double-layer cooling device for a drift tube, a drift tube and a cooling method

Abstract

A kind of drift tube double-layer cooling device, drift tube and cooling method belong to the technical field of particle accelerator.Cooling device includes: main cooling part, its inner cavity includes inner ring cooling cavity and outer ring cooling cavity along the direction of thickness, support, it has with inner ring cooling cavity communication water inlet channel and with outer ring cooling cavity communication water outlet channel;And at least one nose cone cooling part and adapter cooling part, nose cone cooling part is connected with outer ring cooling cavity by adapter cooling part;Cooling medium flows in cooling device in order: water inlet channel, inner ring cooling cavity, outer ring cooling cavity, adapter cooling part, nose cone cooling part, adapter cooling part, outer ring cooling cavity, water outlet channel, form the cooling flow path of series connection.The main cooling part of the application is approximately multiplied by double-layer series flow channel in the same installation space, does not increase radial dimension can greatly improve heat dissipation area and medium residence time, greatly improve the heat dissipation effect of unit volume, solve the problem of compact space heat dissipation limit.

Description

Technical Field

[0001] This invention relates to the field of particle accelerator technology, and more specifically to a drift tube double-layer cooling device, a drift tube, and a cooling method. Background Technology

[0002] In proton or heavy ion linear accelerators, the drift tube linear accelerator is the core accelerating element. Its basic function is to ensure that charged particles, as they pass through a series of copper drift tubes arranged in a specific pattern, maintain precise synchronization with the high-frequency electric field, thereby continuously gaining energy for acceleration and maintaining good beam quality. Because the drift tubes need to operate at high power levels (megawatts) and in a vacuum environment with high duty cycles, ohmic losses due to resistance on the metal surface are converted into a large amount of Joule heat. If this heat is not dissipated in a timely and uniform manner by water flow, it will cause irreversible thermal deformation of the drift tube. Inadequate heat dissipation can alter even small dimensional changes in the entire accelerating cavity, such as the resonant frequency and axial electric field distribution, causing severe frequency detuning, making it impossible to maintain an stable accelerating electric field, ultimately leading to increased beam loss or even equipment failure. Furthermore, localized overheating can damage the entire drift tube structure. Therefore, an efficient and reliable heat dissipation system is a prerequisite for the long-term stable operation of the drift tube and the entire accelerator.

[0003] To achieve higher acceleration efficiency, linear accelerators employ a drift tube structure with a nose cone. Designing both ends of the drift tube as tapered structures allows for a larger effective shunt impedance, improves the electric field distribution in the acceleration gap, and reduces cavity power consumption. Its advantages include a significantly increased shunt impedance, resulting in higher beam energy gain; simultaneously, the embedded electric quadrupole magnet provides ideal lateral focusing force, achieving beam quality that meets physical requirements. However, the improved electromagnetic performance also brings corresponding engineering challenges; its complex manufacturing process and limited space pose challenges to the heat dissipation module.

[0004] In existing technologies, to address the challenge of excessive temperature rise in drift tubes with nose cones, a cooling sleeve fitted to the inner wall is typically installed within the drift tube's internal cavity, and a cooling medium is introduced through external piping. However, with increasingly compact acceleration structure designs, the space available for arranging cooling channels within the drift tube has become extremely limited. The lateral dimensions of the nose cone section of the drift tube are strictly limited, posing a challenge to traditional single-layer, single-path cooling channel designs. Cooling via metal heat conduction results in a temperature gradient problem, leading to higher temperatures at the nose cone. The deformation at this point has the greatest impact on high-frequency characteristics, and as the high-frequency duty cycle and inlet power gradually increase, the heat dissipation effect becomes insufficient to meet the requirements of the drift tube. Summary of the Invention

[0005] The main technical problem solved by this invention is to overcome the spatial limitations of the internal cooling channels of the drift tube without changing its basic shape and installation dimensions, thereby doubling the coolant flow rate and heat exchange efficiency. According to a first aspect, one embodiment provides a double-layer cooling device for a drift tube, comprising:

[0006] The main cooling component has an inner cooling cavity and an outer cooling cavity along its thickness direction, and the inner cooling cavity and the outer cooling cavity are connected by a communication port.

[0007] A support member is connected to the main cooling member, and the support member has a water inlet channel communicating with the inner ring cooling cavity and a water outlet channel communicating with the outer ring cooling cavity.

[0008] At least one nose cone cooling element and a transition cooling element, the nose cone cooling element being disposed on one side of the main cooling element and connected in series with the outer ring cooling cavity via the transition cooling element; and

[0009] A flow guiding structure is provided inside the main cooling component to guide the cooling medium to flow sequentially through the inner ring cooling cavity and the outer ring cooling cavity along a predetermined path.

[0010] The cooling medium flows sequentially through the following components in the cooling device: the water inlet channel, the inner ring cooling cavity, the connecting port, the outer ring cooling cavity, the adapter cooling component, the nose cone cooling component, the adapter cooling component, the outer ring cooling cavity, and the water outlet channel, forming a series cooling flow path.

[0011] In one embodiment, the outer ring cooling cavity is divided into a first cavity, a transition cavity, and a final cavity, and the inner ring cooling cavity is in communication with the first cavity;

[0012] The nose cone cooling component is provided in two sets, namely a first nose cone cooling component and a second nose cone cooling component, which are respectively disposed on both sides of the main cooling component; the transition cooling component is provided in two sets, namely a first transition cooling component and a second transition cooling component.

[0013] The first transition cooling component connects the first cavity, the first nose cone cooling component, and the transition cavity, and is configured to: introduce the cooling medium in the first cavity into the first nose cone cooling component, and then guide the cooling medium flowing out of the first nose cone cooling component to the transition cavity; the second transition cooling component connects the transition cavity, the second nose cone cooling component, and the final cavity, and is configured to: introduce the cooling medium in the transition cavity into the second nose cone cooling component, and then guide the cooling medium flowing out of the second nose cone cooling component to the final cavity.

[0014] In one embodiment, the support member includes an inner layer pipe, a middle layer pipe, and an outer layer pipe arranged coaxially. The water inlet channel is formed between the inner layer pipe and the middle layer pipe and is connected to the inner ring cooling cavity. The water outlet channel is formed between the middle layer pipe and the outer layer pipe and is connected to the final cavity.

[0015] The cooling medium flows sequentially through the following components in the cooling device: the water inlet channel, the inner ring cooling chamber, the first chamber, the first transition cooling component, the first nose cone cooling component, the first transition cooling component, the transition chamber, the second transition cooling component, the second nose cone cooling component, the second transition cooling component, the final chamber, and the water outlet channel, forming a series cooling flow path.

[0016] In one embodiment, the main cooling component, the first nose cone cooling component, and the second nose cone cooling component are all configured as sleeve structures, the inner ring cooling cavity and the outer ring cooling cavity are both arranged in annular channels, and the shape of the main cooling component, the first nose cone cooling component, and the second nose cone cooling component matches the shape of the inner wall of the drift tube.

[0017] In one embodiment, a communication port is provided between the first cavity and the inner ring cooling cavity. The flow guiding structure includes an inner ring liquid baffle strip, which is disposed in the inner ring cooling cavity and located between the communication port and the support member, so as to guide the cooling medium to flow along the annular channel of the inner ring cooling cavity to the communication port.

[0018] In one embodiment, the flow guiding structure further includes an outer ring liquid-blocking strip, which is disposed in the outer ring cooling cavity and located between the connecting port and the support member, so as to isolate the first cavity and the last cavity and guide the cooling medium to flow to the water outlet channel.

[0019] In one embodiment, the inner and outer ring liquid baffles are arranged radially overlapping along the main cooling component, and the connecting port, the inner and outer ring liquid baffles are all located close to the support component.

[0020] In one embodiment, a plurality of baffles are provided in the water path of the inner cavity of the main cooling component, the first nose cone cooling component, and the second nose cone cooling component to divide the channel of the cooling medium into a plurality of sequentially connected flow units, and the channel openings of two adjacent baffles are arranged far apart from each other to extend the path length of the cooling medium.

[0021] According to a second aspect, one embodiment provides a drift tube, comprising:

[0022] The outer shell includes a first nasal cone segment, a cylindrical segment, and a second nasal cone segment arranged sequentially.

[0023] As described above, the drift tube double-layer cooling device is disposed inside the outer shell; wherein, the shape of the nose cone cooling component matches the inner wall of the first nose cone segment and the second nose cone segment, and the shape of the main cooling component matches the inner wall of the cylindrical segment.

[0024] A coil assembly includes a coil portion and a wire, the coil portion being disposed within the inner cavity of the cylindrical section, and the wire being arranged passing through the support member;

[0025] as well as

[0026] The core tube is coaxially arranged at the center of the coil section and passes through both ends of the outer casing.

[0027] According to a third aspect, one embodiment provides a double-layer cooling method for a drift tube, employing the aforementioned double-layer cooling device for drift tubes, comprising the following steps:

[0028] The cooling medium is introduced into the drift tube cooling device from the water inlet channel of the support member. The drift tube cooling device is located inside the drift tube and matches the inner wall of the drift tube.

[0029] The cooling medium enters the inner ring cooling cavity of the main cooling component and flows along the annular channel of the inner ring cooling cavity at least once under the guidance of the flow guiding structure;

[0030] The cooling medium enters the outer ring cooling chamber through the connecting port;

[0031] The cooling medium flows sequentially through the outer ring cooling cavity, the transition cooling component, and the nose cone cooling component, and then returns from the transition cooling component to the outer ring cooling cavity;

[0032] The cooling medium is discharged from the water outlet channel.

[0033] According to the above embodiments, the drift tube cooling device and drift tube are designed with corresponding matching cooling components for the geometric features of the nose cone. The series cooling paths force the cooling medium to flow through all surfaces that need to be cooled, eliminating dead zones. The main cooling component uses a double-layer series flow channel of inner and outer cooling chambers to approximately double the effective cooling path within the same installation space. This significantly increases the heat dissipation area and medium residence time without increasing the radial dimension, greatly improving the heat dissipation effect per unit volume and solving the problem of heat dissipation limits in compact spaces. The coaxial dual-channel design within the support component achieves compact integration and zero external interference, while the single-pass series water path ensures uniform flow distribution. The support component also serves as a structural support and inlet / outlet water channel, resulting in a compact structure that reduces external piping. This makes the cooling device easy to integrate into limited spaces such as drift tubes or particle accelerators, facilitating assembly and improving the stability of the drift tube. Attached Figure Description

[0034] Figure 1This is a schematic diagram of the overall structure of a drift tube with a double-layer cooling device in one embodiment.

[0035] Figure 2 This is a schematic diagram of the overall exploded structure of a drift tube with a double-layer cooling device in one embodiment;

[0036] Figure 3 This is an overall exploded view of the drift tube cooling device in another embodiment;

[0037] Figure 4 This is a schematic diagram of the radial section of the main cooling component in another embodiment;

[0038] Figure 5 for Figure 4 Enlarged cross-sectional view of the connection between the main cooling component and the support component;

[0039] Figure 6 This is an exploded view of the connection between the main cooling component and the support component in another embodiment;

[0040] Figure 7 An exploded view of the internal structure of the double-layer cooling device in another embodiment;

[0041] Figure 8 This is a schematic diagram of the internal structure of the main cooling element and / or the nose cone cooling element in another embodiment;

[0042] Figure 9 This is a schematic diagram of the transverse cross-section of the support member in another embodiment;

[0043] Figure 10 This is a schematic diagram of the vertical cross-section of the support member in another embodiment.

[0044] Figure label:

[0045] 10. Cooling device;

[0046] 100. Main cooling components;

[0047] 101. Inner ring cooling chamber; 1011. Inner ring baffle; 102. Outer ring cooling chamber; 1021. First chamber; 1022. Transition chamber; 1023. Final chamber; 1024. Outer ring baffle; 103. Connecting port; 104. Spacer; 105. Rib; 1051. Channel opening;

[0048] 200. Support component; 201. Inner layer pipe; 202. Middle layer pipe; 203. Outer layer pipe;

[0049] 204. Water inlet channel; 205. Water outlet channel; 206. Water inlet pipe; 207. Water outlet pipe;

[0050] 300. First nose cone cooling component; 301. Baffle strip;

[0051] 400. Second nose cone cooling component;

[0052] 500, First transition cooling component; 501, Liquid inlet flow section; 502, Liquid outlet flow section; 503, Connecting section;

[0053] 600. Second adapter cooling component;

[0054] 20. Outer shell; 21. First nasal cone segment; 22. Cylindrical segment; 23. Second nasal cone segment;

[0055] 30. Coil assembly; 31. Coil section; 32. Wire;

[0056] 40. Core tube. Detailed Implementation

[0057] The present invention will now be described in further detail with reference to specific embodiments and accompanying drawings. Similar elements in different embodiments are referred to by associated similar element reference numerals. In the following embodiments, many details are described to facilitate a better understanding of the invention. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, certain operations related to the present invention are not shown or described in the specification. This is to avoid obscuring the core parts of the invention with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.

[0058] Furthermore, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments. At the same time, the steps or actions in the method description can be rearranged or adjusted in a manner obvious to those skilled in the art. Therefore, the various orders in the specification and drawings are only for the clear description of a particular embodiment and do not imply a necessary order, unless otherwise stated that a particular order must be followed.

[0059] The serial numbers assigned to components in this document, such as "first" and "second," are used only to distinguish the described objects and have no sequential or technical meaning. The terms "connection" and "linkage" used in this invention, unless otherwise specified, include both direct and indirect connections (linkages).

[0060] Currently, commonly used drift tubes generally employ a hollow cylindrical structure. The internal cavity facilitates the insertion of a matching cylindrical water-cooling sleeve, allowing coolant to flow through the main area of ​​the drift tube. However, in drift tubes with a nose cone, the nose cone structure itself occupies critical space at the front end, preventing the regularly shaped cylindrical cooling sleeve from extending forward and tightly fitting the inner wall of the nose cone region. In actual heat dissipation designs, the cooling sleeve is often only placed within the cylindrical section 22 at the rear of the drift tube. This results in the nose cone tip and surrounding area, where heat generation is most concentrated and thermal deformation is most sensitive, becoming a weak point in the heat dissipation path. Heat accumulates at this location and is difficult to remove directly and efficiently, easily forming localized high-temperature points. This localized overheating can not only cause material performance degradation but also directly lead to differential thermal expansion in the nose cone region, disrupting the precise geometry of the acceleration gap. Ultimately, this negates the electrical performance advantages brought by the nose cone design, becoming a key bottleneck restricting the reliability and ultimate performance of such high-performance drift tubes.

[0061] In existing technologies, to address the heat dissipation problem of drift tubes with protruding nose cones, a cooling sleeve fitted to the inner wall is typically installed inside the drift tube cavity, and coolant is introduced through external piping. However, with accelerator designs becoming increasingly compact, the space available for arranging cooling channels inside the drift tube has become extremely limited. Under the condition of strictly limited radial dimensions, traditional single-layer, single-path cooling channel designs face a fundamental bottleneck: there is a direct contradiction between the effective cross-sectional area of ​​the channel and the heat dissipation surface area.

[0062] Existing single-layer cooling channels face a direct contradiction between the effective cross-sectional area of ​​the channel and the heat dissipation surface area within a compact space: increasing the channel cross-sectional area to reduce flow resistance reduces the heat dissipation surface area; conversely, increasing the heat dissipation surface area limits the channel cross-sectional area. In related fields, technologies exist for setting multiple cooling channels along the wall thickness to increase the heat exchange area. However, in the specific application scenario of drift tubes, due to extremely limited internal space, extremely high vacuum sealing requirements, and the need to accommodate the complex geometry of the nose cone region, combining multi-layer channel technology with the cooling requirements of drift tubes is not a simple structural transplant; it faces technical challenges in channel layout, sealing reliability, and manufacturing processes. Current technologies have not yet disclosed a solution that can effectively double the coolant flow rate and heat exchange efficiency without changing the basic shape and installation dimensions of the drift tube.

[0063] This invention employs an innovative flow channel topology design, featuring a double-layer structure with an inner and outer cooling cavity along the thickness direction within the main cooling component. This, combined with a flow guiding structure, directs the cooling medium to first achieve uniform heat exchange throughout the entire circumference of the inner ring, then enters the upper outer ring through a connecting port, and is discharged after passing through a series of nose cone cooling components. This effectively doubles the cooling path and medium residence time within the same installation space. In other words, without altering the basic shape and installation dimensions of the drift tube, it overcomes the spatial limitations of its internal cooling channels, achieving a significant increase in coolant flow rate and heat exchange efficiency.

[0064] Specifically, in one embodiment, please refer to Figure 1 , Figure 2 and Figure 3 This embodiment discloses a drift tube double-layer cooling device, which is suitable for forced liquid cooling of heated elements in drift tubes or particle accelerators. It mainly includes: a main cooling component 100, a first nose cone cooling component 300, a second nose cone cooling component 400, a support component 200, a first transition cooling component 500, a second transition cooling component 600, and a flow guiding structure.

[0065] Please refer to Figure 3 , Figure 4 and Figure 5 The main cooling component 100 includes an inner cooling cavity 101 and an outer cooling cavity 102 along its thickness direction. The outer cooling cavity 102 is divided into a first cavity 1021, a transition cavity 1022, and a final cavity 1023. The support component 200 integrates a water inlet channel 204 and a water outlet channel 205. The cooling medium flows sequentially through the following in the cooling device 10: water inlet channel 204, inner cooling cavity 101, first cavity 1021, first transition cooling component 500, first nose cone cooling component 300, first transition cooling component 500, transition cavity 1022, second transition cooling component 600, second nose cone cooling component 400, second transition cooling component 600, final cavity 1023, and water outlet channel 205, forming a series cooling flow path.

[0066] Please refer to Figure 4 , Figure 5 and Figure 6 The main cooling component 100 is configured as a circular sleeve structure, and its annular shell cavity is configured as a double-layer cavity structure, namely an inner ring cooling cavity 101 and an outer ring cooling cavity 102 that are interconnected. A connecting port 103 is provided between the first cavity 1021 and the inner ring cooling cavity 101. After the cooling medium enters the annular channel of the inner ring cooling cavity 101 from the water inlet channel 204, it enters the first cavity 1021 of the outer ring cooling cavity 102 through the connecting port 103. The connecting port 103 is located on the side of the first cavity 1021 near the support component 200 so that the cooling liquid can flow through the entire annular channel.

[0067] Please refer to Figure 4 , Figure 5and Figure 6 The flow guiding structure includes an inner ring baffle strip 1011 disposed in the inner ring cooling cavity 101, and the inner ring baffle strip 1011 is disposed between the connecting port 103 and the support member 200, blocking the connection between the water inlet channel 204 and the connecting port 103, while guiding the cooling medium to flow in a specific direction to the connecting port 103, that is, along the side away from the inner ring baffle strip 1011, around the annular cavity to the other side of the inner ring baffle strip 1011, and entering the first cavity 1021 of the outer ring cooling cavity 102 through the connecting port 103.

[0068] Please refer to Figure 4 , Figure 5 and Figure 6 The flow guiding structure also includes an outer ring baffle strip 1024 disposed in the outer ring cooling chamber 102, and the outer ring baffle strip 1024 is disposed between the connecting port 103 and the support member 200, blocking the connection between the water outlet channel 205 and the connecting port 103, while isolating the first chamber 1021 and the last chamber 1023 and guiding the cooling medium to flow to the water outlet channel 205.

[0069] In this embodiment, please refer to Figure 5 The inner ring baffle 1011 and the outer ring baffle 1024 are arranged radially overlapping along the main cooling component 100, that is, the inner ring baffle 1011 and the outer ring baffle 1024 are arranged in the same diameter direction of the main cooling component 100, and the connecting port 103, the inner ring baffle 1011 and the outer ring baffle 1024 are all arranged close to the support component 200, and are arranged as a whole on one side of the first cavity 1021 so that the cooling liquid can flow through the entire annular channel.

[0070] Cooling liquid enters the inner cooling chamber 101 through the inlet channel 204 and flows around the inner wall of the drift tube body at least once to complete the first stage of sufficient heat exchange. Subsequently, all cooling media must pass through the connecting port 103, rise as a whole and enter the outer cooling chamber 102, and pass through the first chamber 1021, the first transition cooling component 500, the first nose cone cooling component 300, the first transition cooling component 500, the transition chamber 1022, the second transition cooling component 600, the second nose cone cooling component 400, the second transition cooling component 600, and the final chamber 1023 in sequence, and finally flow out through the outlet channel 205 to complete the second stage of sufficient heat exchange, forming a series of cooling flow paths. Under the inherent condition of extremely limited internal space in drift tubes, this application significantly extends the forced flow path and heat exchange time of coolant near high-temperature walls without increasing the radial dimension of the system through an innovative flow channel topology design. This fundamentally improves the heat dissipation power density per unit space, ensuring the thermal and frequency stability of the compact drift tube under extreme operating conditions.

[0071] For further details, please refer to... Figure 7The outer ring cooling chamber 102 is provided with two partition bars 104. The length of the partition bars 104 is set along the axial direction of the main cooling component 100. Together with the outer ring liquid baffle 1024, they form three isolated chambers, which are sequentially the first chamber 1021, the transition chamber 1022 and the last chamber 1023 along the circumference of the main cooling component 100. The first chamber 1021 and the last chamber 1023 are located on both sides of the support 200 and are separated by the outer ring liquid baffle 1024. The transition chamber 1022 is located between the first chamber 1021 and the last chamber 1023 and is used for the reversal of the cooling medium. It is separated by the two partition bars 104.

[0072] Please refer to Figure 3 , Figure 6 and Figure 7 The first nose cone cooling element 300 and the second nose cone cooling element 400 have identical structures and are configured as annular channels, respectively located on both sides of the main cooling element 100 along its axial direction. Both the first nose cone cooling element 300 and the second nose cone cooling element 400 have internal cooling chambers for heat exchange with components to be cooled, such as the inner wall of the drift tube. In this embodiment, the shapes of the main cooling element 100, the first nose cone cooling element 300, and the second nose cone cooling element 400 match the shape of the inner wall of the drift tube, allowing them to directly contact the inner surface of the nose cone for heat exchange, ensuring close contact for efficient heat conduction.

[0073] Please refer to Figure 3 , Figure 6 and Figure 7 The first transition cooling component 500 and the second transition cooling component 600 have the same structure. The first transition cooling component 500 connects the first cavity 1021, the first nose cone cooling component 300 and the transition cavity 1022, and is configured to: introduce the cooling medium in the first cavity 1021 into the first nose cone cooling component 300, and then guide the cooling medium flowing out of the first nose cone cooling component 300 to the transition cavity 1022; the second transition cooling component 600 connects the transition cavity 1022, the second nose cone cooling component 400 and the final cavity 1023, and is configured to: introduce the cooling medium in the transition cavity 1022 into the second nose cone cooling component 400, and then guide the cooling medium flowing out of the second nose cone cooling component 400 to the final cavity 1023.

[0074] For details, please refer to Figure 3 , Figure 6 and Figure 7The first transition cooling component 500 includes an inlet flow section 501 and an outlet flow section 502. Both ends of the inlet flow section 501 and the outlet flow section 502 are provided with docking sections 503 for water inlet and outlet. In this embodiment, the inlet flow section 501 and the docking sections 503 at both ends form a liquid inlet flow channel. The inlet flow section 501 corresponding to the first transition cooling component 500 is used to connect the first cavity 1021 and the first nose cone cooling component 300. The inlet flow section 501 corresponding to the second transition cooling component 600 is used to connect the transition cavity 1022 and the second nose cone cooling component 400. The liquid outlet transfer section 502 and the docking sections 503 at both ends form a liquid outlet channel. The liquid outlet transfer section 502 corresponding to the first transition cooling component 500 is used to connect the first nose cone cooling component 300 and the transition cavity 1022. The liquid outlet transfer section 502 corresponding to the second transition cooling component 600 is used to connect the second nose cone cooling component 400 and the final cavity 1023.

[0075] In this embodiment, the same adapter cooling component body can be designed and manufactured as a single unit, internally divided into independent liquid inlet and liquid outlet spaces. The main cooling component 100, the first nose cone cooling component 300, and the second nose cone cooling component 400 are provided with corresponding mating interfaces for the docking portion 503 to communicate with the internal cavity. A baffle 301 is provided between the two mating interfaces in the internal cavity of the first nose cone cooling component 300 and the second nose cone cooling component 400 to guide the cooling medium entering from one side of the liquid inlet flow portion 501 to flow in a fixed direction to the other side of the baffle 301, and then out from the liquid outlet flow portion 502. Alternatively, the adapter cooling component on the same side can be configured as two independent parts for the liquid inlet flow portion 501 and the liquid outlet flow portion 502, such as pipes, for liquid inlet and liquid outlet respectively.

[0076] Please refer to Figure 3 , Figure 6 and Figure 7 The cooling medium in the first cavity 1021 enters the first nose cone cooler 300 through the liquid inlet transfer section 501 corresponding to the first transition cooler 500. It flows in a fixed direction within the internal channel of the first nose cone cooler 300 and reaches the other side of the baffle 301. The cooling medium then flows out from the liquid outlet transfer section 502 and enters the transition cavity 1022 of the main cooler 100. The cooling medium in the transition cavity 1022 enters the second nose cone cooler 400 through the liquid inlet transfer section 501 corresponding to the second transition cooler 600. It flows in a fixed direction within the internal channel of the second nose cone cooler 400 and reaches the other side of the baffle 301. The cooling medium then flows out from the liquid outlet transfer section 502 and enters the final cavity 1023 of the main cooler 100, completing the circulation of the cooling medium.

[0077] For further details, please refer to... Figure 8In one embodiment, a plurality of baffles 105 are provided in the water channels within the main cooling component 100, the first nose cone cooling component 300, and the second nose cone cooling component 400. Specifically, the plurality of baffles 105 are parallel to each other and arranged radially along the main cooling component 100. The length direction of the baffles 105 is parallel to the axial direction of the main cooling component 100, so as to divide the channel of the cooling medium into a plurality of sequentially connected flow units. The length of the baffles 105 is less than the width of the inner cavity of the main cooling component 100, so as to form a channel opening 1051 between the baffles 105 and the inner cavity of the main cooling component 100. The channel openings 1051 of two adjacent baffles 105 are arranged far apart from each other, so that the flow unit as a whole is wavy, thereby extending the path length of the cooling medium.

[0078] In another embodiment, please refer to Figure 6 , Figure 9 and Figure 10 The support member 200 is a hollow long rod, serving as both structural support and a cooling medium delivery channel. The support member 200 is radially connected to the main cooling member 100 and includes three coaxially arranged layers of pipes: an inner layer pipe 201, a middle layer pipe 202, and an outer layer pipe 203. A water inlet channel 204 is formed between the inner layer pipe 201 and the middle layer pipe 202, communicating with the inner ring cooling chamber 101. The outer ring cooling chamber 102 is directly isolated by the wall of the middle layer pipe 202. A water outlet channel 205 is formed between the middle layer pipe 202 and the outer layer pipe 203, communicating with the final cavity 1023 of the outer ring cooling chamber 102. Both the water inlet channel 204 and the water outlet channel 205 are annular cylindrical channels.

[0079] For details, please refer to Figure 6 , Figure 9 and Figure 10 The main cooling component 100 can generally include a three-layer structure: an inner ring, an isolation ring, and an outer ring. The inner and outer rings are used to cool the drift tube. The inner ring cooling cavity 101 is between the inner ring and the isolation ring, and the outer ring cooling cavity 102 is between the isolation ring and the outer ring. The connecting port 103 is opened on the isolation ring. In this embodiment, the inner ring, the isolation ring, and the outer ring are provided with through openings at the ends of the corresponding support members 200 so as to connect with each inner cavity of the main cooling component 100. That is, the end of the inner layer pipe 201 is connected to the opening of the inner ring so that the internal structure of the drift tube can be led out; the middle layer pipe 202 is connected to the opening of the isolation ring, that is, the water inlet channel 204 between the middle layer pipe 202 and the inner layer pipe 201 is connected to the inner ring cooling cavity 101. The outer pipe 203 is connected to the outer ring opening, that is, the water outlet channel 205 between the outer pipe 203 and the middle pipe 202 is connected to the outer ring cooling chamber 102, thereby achieving water inlet and outlet isolation through the pipe arms of each layer of pipes.

[0080] In one embodiment, the inner ring, insulating ring, and outer ring of the main cooling component 100 can be manufactured by separate machining followed by assembly. The inner and outer rings are formed by precision turning or milling, and the insulating ring is formed into a connecting port 103 by laser cutting or EDM. The three are connected as a whole by vacuum brazing or electron beam welding. The inner ring baffle 1011 and the outer ring baffle 1024 can be integrally formed with the inner wall of the corresponding cavity, or pressed in with an interference fit and then fixed with silver brazing to ensure structural reliability under high-frequency vibration and temperature difference cycling. The machining accuracy of the connecting port 103 is controlled within ±0.05mm to ensure uniform flow distribution. For further details, please refer to... Figure 9 and Figure 10 The support component 200 also includes an inlet pipe 206 and an outlet pipe 207. Both the inlet pipe 206 and the outlet pipe 207 are arranged on the side away from the main cooling component 100. The outer pipe 203 has an outer inlet and an outlet, and the middle pipe 202 has an inner inlet. The inlet pipe 206 passes through the outer inlet and the inner inlet and is connected to the inlet channel 204. The outlet pipe 207 passes through the outlet and is connected to the outlet channel 205.

[0081] In another embodiment, the inlet channel (204) and the outlet channel (205) have the same cross-sectional area. Specifically, by reasonably selecting the pipe diameter and wall thickness of the inner pipe (201), the middle pipe (202), and the outer pipe (203), the cross-sectional area of ​​the annular inlet channel (204) formed between the inner pipe (201) and the middle pipe (202) is made equal to the cross-sectional area of ​​the annular outlet channel (205) formed between the middle pipe (202) and the outer pipe (203). For example, the wall thickness of the middle pipe (202) can be adjusted so that the difference between its outer diameter and the outer diameter of the inner pipe (201), and the difference between the inner diameter of the outer pipe (203) and the outer diameter of the middle pipe (202) satisfy a specific geometric relationship, thereby achieving equal cross-sectional areas of the two annular channels.

[0082] The technical advantages of this design are as follows: when the cross-sectional areas of the inlet channel (204) and the outlet channel (205) are the same, the inlet and outlet flow velocities are equal under the same flow rate, the flow resistance of the fluid in the two channels tends to be balanced, the system pressure drop is evenly distributed, and the pressure drop imbalance caused by the difference in flow velocity is avoided. This helps the cooling system to operate stably, reduces pumping power consumption, and ensures that the flow distribution of the cooling medium in each cooling part is more uniform. In addition, the consistent inlet and outlet flow velocities can also keep the heat exchange efficiency of the cooling medium in the inlet and outlet channels consistent, avoid uneven local temperature rise caused by the difference in flow velocity, and further improve the overall cooling uniformity and efficiency of the cooling device (10).

[0083] In this embodiment, to achieve optimal cooling uniformity and minimum flow resistance, the volumes of the first cavity 1021, transition cavity 1022, and final cavity 1023 of the outer ring cooling chamber 102 are optimized according to the temperature rise and flow rate of the cooling medium, ensuring that the flow rate within each nose cone cooling element is substantially equal. The layers of pipes in the support member 200 and their corresponding openings, as well as the inner and outer ring liquid-blocking strips 1024 and their corresponding cavity inner walls, are all fitted with interference fits and supplemented with sealing rings to prevent leakage. The first transition cooling element 500 and the second transition cooling element 600 are made of materials with good thermal conductivity, and their internal channel surfaces are smooth to reduce pressure loss.

[0084] In this embodiment, the dual-layer cooling device 10 operates as follows: First, the cooling medium enters the water inlet channel 204 of the support member 200 from the external cooling system through the water inlet pipe 206. That is, the cooling medium enters between the inner layer pipe 201 and the middle layer pipe 202, flowing downwards to the lower end. The lower opening of the water inlet channel 204 directly connects to the inner ring cooling chamber 101, allowing the cooling medium to directly enter the inner ring cooling chamber 101. Guided by the inner ring baffle strip 1011, the cooling medium flows along the annular flow channel within the chamber, circling the inner wall of the drift tube body for at least one complete cycle, completing the first stage of sufficient heat exchange. Subsequently, all the cooling medium must pass through the connecting port 103, rise as a whole, and enter the first chamber 1021 of the outer ring cooling chamber 102. Because the outer ring baffle strip 1024 closes the water outlet channel 205 on the side of the first chamber 1021 and the support member 200, the cooling medium cannot directly enter the water outlet channel 205 and can only flow along the first chamber 1021 towards the side away from the support member.

[0085] Then, the cooling medium flows along the first cavity 1021 and absorbs heat until it reaches the interface of the first cavity 1021. It then enters the first nose cone cooling component 300 through the liquid inlet transfer section 501 corresponding to the first transition cooling component 500, and flows in a fixed direction within the internal channel of the first nose cone cooling component 300 to reach the interface on the other side of the baffle 301. The cooling medium flows out from the liquid outlet transfer section 502 and enters the transition cavity 1022 of the main cooling component 100. The cooling medium in the transition cavity 1022 enters the second nose cone cooling component 400 through the liquid inlet transfer section 501 corresponding to the second transition cooling component 600, and flows in a fixed direction within the internal channel of the second nose cone cooling component 400 to reach the other side of the baffle 301. The cooling medium flows out from the corresponding liquid outlet transfer section 502 and enters the final cavity 1023 of the main cooling component 100, thus achieving heat absorption of the two nose cone portions.

[0086] Finally, the cooling medium flows from the end chamber 1023 to the support 200, and through the water outlet channel 205 at the lower end of the support 200, the cooling medium flows upward and is discharged through the water outlet pipe 207, returning to the external cooling system, thus completing the cooling of the drift tube.

[0087] As can be seen, the cooling medium flows sequentially through the following parts in the entire device: inlet pipe 206, inlet channel 204, inner ring cooling chamber 101, first chamber 1021, liquid inlet flow section 501 of the first transition cooling component 500, first nose cone cooling component 300, liquid outlet flow section 502 of the first transition cooling component 500, transition chamber 1022, liquid inlet flow section 501 of the second transition cooling component 600, second nose cone cooling component 400, liquid outlet flow section 502 of the second transition cooling component 600, final chamber 1023, water outlet channel 205, and water outlet pipe 207, forming a complete series cooling flow path.

[0088] In this application, the series path forces the cooling medium to flow sequentially through all surfaces that need to be cooled, including the inner wall of the main cooling component 100 and the nose cone positions corresponding to the first nose cone cooling component 300 and the second nose cone cooling component 400, without any flow dead zones that are not flushed by the cooling medium; the coaxial dual-channel design within the support component 200 achieves compact integration and zero external interference; and the single-pass series water path ensures absolute uniformity of flow distribution and determinism of the process.

[0089] In this application, the double-layer series flow channel design of the main cooling component 100 achieves an approximate doubling of the effective flow path of the cooling medium within the same installation space. This is equivalent to significantly increasing the heat dissipation area and medium residence time without increasing the radial dimension, resulting in a significant improvement in the heat dissipation power density per unit volume, fundamentally solving the heat dissipation limit problem in compact spaces.

[0090] In this application, the unique flow path logic of "uniform preheating of the lower inner ring and orderly distribution of the upper outer ring" combined with the deterministic flow distribution brought by the integrated channel of the support component 200 and the inherent flow consistency of the series circuit ensures that the circumferential and axial temperature gradients of the drift tube are minimized, providing a physical basis for achieving extremely high frequency stability and beam quality.

[0091] In this application, the power supply, water inlet, and water outlet functions are integrated into a single compact structure through the coaxial multi-layer pipe design inside the support component 200, which greatly saves space and simplifies external connections. All cooling channels are completely built into solid materials outside the vacuum chamber, completely eliminating the major risk of medium leakage contaminating the ultra-high vacuum environment, and significantly improving system stability and operational safety.

[0092] The above embodiments are merely preferred embodiments of the present invention. There are also some alternative embodiments without departing from the concept of the present invention, which are also within the scope of the methods described in this specification.

[0093] For example, in one embodiment, the first transition cooling component 500 and the second transition cooling component 600 can be integrally formed multi-channel connectors or components composed of multiple pipe connectors and connecting pipes, as long as they can realize the function of introducing the cooling medium of the first cavity 1021 into the first nose cone cooling component 300 and then guiding it back to the transition cavity 1022.

[0094] For example, in another embodiment, for a drift tube with a single nose cone, the outer cooling chamber 102 can adopt a simplified two-chamber structure. In this embodiment, the cooling device 10 includes a main cooling component 100, a nose cone cooling component disposed on one side of the main cooling component 100, a transition cooling component, and a support component 200. Unlike the aforementioned three-chamber scheme, the outer cooling chamber 102 in this embodiment has only one partition 104, which, together with the flow guiding structure, forms two isolated chambers: a first chamber 1021 and a last chamber 1023, excluding the transition chamber 1022.

[0095] Specifically, the first cavity 1021 serves as the water inlet cavity and is connected to the water inlet channel 204 of the support member 200; the last cavity 1023 serves as the water outlet cavity and is connected to the water outlet channel 205 of the support member 200. The nose cone cooling component is located on one side of the main cooling component 100, corresponding to the position of the single-sided nose cone section of the drift tube. It has a cooling chamber inside, and its shape matches the inner wall shape of the single-sided nose cone section of the drift tube. The transition cooling component connects the first cavity 1021, the nose cone cooling component, and the last cavity 1023. It includes an inlet flow section 501 and an outlet flow section 502: the inlet flow section 501 connects the first cavity 1021 and the nose cone cooling component, introducing the cooling medium from the first cavity 1021 into the nose cone cooling component; the outlet flow section 502 connects the nose cone cooling component and the last cavity 1023, guiding the cooling medium flowing out of the nose cone cooling component to the last cavity 1023.

[0096] Therefore, the cooling medium flows sequentially through the following in the cooling device 10 of this embodiment: inlet pipe 206, inlet channel 204, inner ring cooling chamber 101, connecting port 103, first chamber 1021, liquid inlet transfer section 501 of the transition cooling component, nose cone cooling component, liquid outlet transfer section 502 of the transition cooling component, final chamber 1023, water outlet channel 205, and water outlet pipe 207, forming a complete series cooling flow path. Compared with the aforementioned three-chamber scheme, the two-chamber scheme of this embodiment is suitable for drift tube structures with only one nose cone. The structure is simpler, reducing one reversing transition chamber and one nose cone cooling component, but still achieving series cooling without flow dead zones, ensuring uniform and efficient cooling of the key area of ​​the nose cone. This scheme is particularly suitable for applications with low beam energy or limited space, reducing manufacturing costs and assembly complexity while ensuring cooling effect.

[0097] For example, in another embodiment, for drift tubes requiring more cooling stations, two or more nose cone cooling elements can be set on each side of the main cooling element 100 to achieve multi-stage series cooling. Taking four nose cone cooling elements as an example, the inner cavity of the outer ring cooling chamber 102 is provided with four partitions 104, which, together with the outer ring liquid baffle 1024, form five isolated chambers: the first chamber 1021, the first transition chamber, the second transition chamber, the third transition chamber, and the last chamber 1023. Among them, the first chamber 1021 is the water inlet chamber, which is connected to the water inlet channel 204; the last chamber 1023 is the water outlet chamber, which is connected to the water outlet channel 205; the three middle chambers, namely the first, second, and third transition chambers, are all reversing chambers, used for the reversing of the cooling medium between adjacent nose cone cooling elements. The water inlet and outlet channel structure of the support 200 remains unchanged, only the number of reversing chambers needs to be increased in the outer ring cooling chamber 102.

[0098] Specifically, two nose cone cooling elements are provided on each side of the main cooling element 100, for a total of four nose cone cooling elements. Two nose cone cooling elements are located on the left side of the main cooling element and two nose cone cooling elements are located on the right side of the main cooling element. Four corresponding transition cooling elements are provided, and the liquid inlet flow section 501 and liquid outlet flow section 502 of each transition cooling element are respectively connected to the adjacent chamber and the corresponding nose cone cooling element. In the cooling device 10 of this embodiment, the cooling medium flows sequentially through: water inlet channel 204, inner ring cooling chamber 101, connecting port 103, first chamber 1021, transition cooling element one, nose cone cooling element one, transition cooling element one, transition chamber one, transition cooling element two, nose cone cooling element two, transition cooling element two, transition chamber two, transition cooling element three, nose cone cooling element three, transition cooling element three, transition chamber three, transition cooling element four, nose cone cooling element four, transition cooling element four, final chamber 1023, and water outlet channel 205, forming a complete series cooling flow path.

[0099] This multi-stage series design allows for flexible expansion of the number of nose cone cooling components based on the drift tube length and heat load distribution. Each additional two nose cone cooling components requires only the addition of a transition cavity 1022 and two corresponding adapter cooling components within the outer cooling chamber 102, demonstrating the modularity and scalability of this invention. This design is particularly suitable for applications with long drift tubes or high heat loads. By increasing the number of cooling stages, cooling efficiency and temperature distribution uniformity can be further improved, ensuring long-term stable operation of the drift tube under high power and high duty cycle conditions.

[0100] For example, in another embodiment, the inner cavity of the main cooling component 100 is provided with three or more cooling chambers along the thickness direction to further increase the heat dissipation area and the residence time of the cooling medium. Taking a three-layer cooling chamber as an example, the inner cavity of the annular shell of the main cooling component 100 is provided with an inner ring cooling chamber 101, a middle ring cooling chamber, and an outer ring cooling chamber 102 in a radial direction from the inside to the outside. The inner ring cooling chamber 101 and the middle ring cooling chamber are connected in series through a first connecting port, and the middle ring cooling chamber and the outer ring cooling chamber 102 are connected in series through a second connecting port, forming a three-stage progressive cooling structure.

[0101] Specifically, the annular shell of the main cooling component 100 comprises a four-layer structure: an inner ring, a first isolation ring, a second isolation ring, and an outer ring. An inner ring cooling cavity 101 is formed between the inner ring and the first isolation ring; a middle ring cooling cavity is formed between the first and second isolation rings; and an outer ring cooling cavity 102 is formed between the second isolation ring and the outer ring. A first connecting port is located on the first isolation ring, and a second connecting port is located on the second isolation ring. After completing the first stage of full-circumference heat exchange in the inner ring cooling cavity 101, the cooling medium enters the middle ring cooling cavity through the first connecting port to complete the second stage of heat exchange; then it enters the outer ring cooling cavity 102 through the second connecting port, and after being connected in series with the transition cooling component and the nose cone cooling component, it is discharged through the water outlet channel 205 to complete the third stage of heat exchange.

[0102] The positions of the connecting ports 103 at each level can be optimized according to the heat load distribution. Corresponding baffles can be installed in each cooling chamber to guide the cooling medium to flow completely around the annular channel. The support component 200 can be equipped with an additional layer of piping to connect to each cooling chamber, or a three-layer piping structure can be used, with the inlet channel 204 connecting to the innermost cooling chamber and the outlet channel 205 connecting to the outermost cooling chamber, with the intermediate layers connected in series via connecting ports. This multi-stage progressive cooling structure further multiplies the effective cooling path within the same installation space, making it suitable for high-power drift tubes with extremely high heat loads and stringent requirements for temperature uniformity.

[0103] For example, in another embodiment, the inner ring cooling cavity 101 is not limited to a complete annular channel. It can adopt a segmented arc-shaped channel or multiple parallel inner ring channels according to the actual heat load distribution and processing requirements, as long as the cooling medium can achieve full circumference coverage of the inner wall of the main cooling component 100.

[0104] For example, in another embodiment, the position of the connecting port 103 is not limited to the side near the first cavity 1021 of the support member 200. The connecting port 103 can be set at any circumferential position of the inner ring cooling cavity 101 according to the heat load distribution of the drift tube, so as to optimize the initial temperature distribution of the cooling medium entering the outer ring cooling cavity 102. This solution achieves active optimization of the temperature distribution of the cooling medium by flexibly adjusting the circumferential position of the connecting port 103, and is suitable for high-power drift tubes with uneven heat load distribution.

[0105] For example, in another embodiment, the structure of the inner ring baffle 1011 and the outer ring baffle 1024 is not limited to an integral strip baffle. Depending on the actual processing technology and flow field optimization requirements, segmented baffles, guide ribs, or locally protruding structures can be used, as long as they can guide the cooling medium to flow in a specific direction. By rationally designing their geometric parameters, precise control of the cooling medium's flow direction and velocity distribution can be achieved to meet cooling requirements under different heat load conditions.

[0106] For example, in another embodiment, the flow direction of the cooling medium can be reversed relative to the aforementioned embodiment. That is, the cooling medium enters the cooling device 10 from the water outlet channel 205, flows through the outer ring cooling chamber 102 and the nose cone cooling component, then enters the inner ring cooling chamber 101 through the connecting port 103, and finally exits from the water inlet channel 204.

[0107] Specifically, in this reverse flow path scheme, the functions of the water inlet channel 204 and the water outlet channel 205 of the support 200 are interchanged, that is, the original water outlet channel 205 serves as the inlet of the cooling medium, and the original water inlet channel 204 serves as the outlet of the cooling medium. The cooling medium enters the outlet channel 205 from the external cooling system through the outlet pipe 207, and then enters the final cavity 1023 of the outer ring cooling chamber 102. Guided by the outer ring baffle 1024, the cooling medium flows from the final cavity 1023 to the second transition cooling component 600, and flows sequentially through the second nose cone cooling component 400, the second transition cooling component 600, the transition cavity 1022, the first transition cooling component 500, the first nose cone cooling component 300, the first transition cooling component 500, and the first cavity 1021. Subsequently, the cooling medium enters the inner ring cooling chamber 101 from the outer ring cooling chamber 102 through the connecting port 103, and flows around the annular channel of the inner ring cooling chamber 101 completely under the guidance of the inner ring baffle 1011, completing the uniform heat exchange on the inner wall of the main cooling component 100. Finally, the cooling medium is discharged from the inlet pipe 206 through the inlet channel 204 and returns to the external cooling system, completing the entire reverse cooling flow path.

[0108] For example, in another embodiment, the support member 200 adopts a two-layer coaxial pipe structure to simplify the manufacturing process and reduce structural complexity. The support member 200 includes a middle layer pipe 202 and an outer layer pipe 203 arranged coaxially, omitting the independent inner layer pipe 201 in the three-layer pipe scheme. An annular water outlet channel 205 is formed between the middle layer pipe 202 and the outer layer pipe 203, and the inner cavity of the middle layer pipe 202 directly serves as the water inlet channel 204. The water inlet channel 204 communicates with the first cavity 1021, and the water outlet channel 205 communicates with the last cavity 1023. The water inlet pipe 206 communicates with the inner cavity of the middle layer pipe 202, and the water outlet pipe 207 communicates with the annular channel between the inner and outer pipes. Compared with the three-layer pipe scheme, the two-layer pipe structure omits the independent inner layer pipe, making the structure simpler and reducing the processing difficulty. If it is necessary to arrange internal pipelines such as wires 32 at the same time, an independent thin pipe can be set in the inner cavity of the middle layer pipe 202 for pipeline arrangement, or the pipeline can be waterproofed.

[0109] For example, in another embodiment, the cooling medium in the cooling device 10 of the present invention is not limited to water, and other coolants can be selected according to actual operating conditions. Applicable coolant types include, but are not limited to: deionized water, suitable for particle accelerator environments sensitive to electromagnetic interference, avoiding corrosion of the coil assembly 30 by ions in ordinary water; ethylene glycol aqueous solution, suitable for low-temperature environments or applications requiring antifreeze protection, with the freezing point controlled by adjusting the ratio of ethylene glycol to water; fluorinated liquids such as perfluorocarbons, which are chemically stable and have good insulation properties, suitable for occasions with extremely high requirements for the electrical insulation of the cooling medium. The structure of the cooling device 10, including the chamber layout, series flow path, and inlet / outlet water channel design of the support 200, is exactly the same as in the main embodiment, only the type of cooling medium is different. When a non-aqueous coolant is selected, the selection of sealing material needs to be adjusted accordingly to ensure chemical compatibility with the coolant used.

[0110] In one embodiment, please refer to Figure 1 and Figure 2 This embodiment provides a drift tube, which is particularly suitable for particle accelerators, such as linear accelerators or cyclotron accelerators, as a beam transmission and focusing component in a high-frequency electric field. It mainly includes a housing 20, a coil assembly 30, a core tube 40, and the drift tube double-layer cooling device 10 described in the above embodiment. The housing 20 includes a first nose cone section 21, a cylindrical section 22, and a second nose cone section 23 arranged sequentially. In this embodiment, the housing 20 includes a low-energy end cap and a high-energy end cap, both of which have a cylindrical mating portion 503 and a conical constricted end. The low-energy and high-energy end caps, when combined, form the aforementioned first nose cone section 21, cylindrical section 22, and second nose cone section 23. Beam holes are provided at both ends of the low-energy and high-energy end caps for the passage of charged particle beams. The coil assembly 30 includes a coil section 31 and a wire 32. The core tube 40 is coaxially arranged at the center of the coil section 31 and passes through both ends of the housing 20. The drift tube double-layer cooling device 10 is disposed inside the housing 20.

[0111] For details, please refer to Figure 1 and Figure 2 The main cooling component 100 is configured to match the inner wall of the cylindrical section 22. The main cooling component 100 of the drift tube double-layer cooling device 10 is fixedly installed in the inner cavity of the cylindrical section 22. The support component 200 extends outward from the main cooling component 100 and serves as a mechanical support arm for the drift tube and a cooling medium delivery channel. The first nose cone cooling component 300 is configured to match the inner wall of the first nose cone section 21, and the second nose cone cooling component 400 is configured to match the inner wall of the second nose cone section 23. They are respectively fitted to the inner walls of the first nose cone section 21 and the second nose cone section 23 to ensure good thermal contact.

[0112] In this embodiment, please refer to Figure 1 and Figure 2The coil section 31 is disposed in the inner cavity of the cylindrical section 22 and is also arranged in the inner ring of the main cooling component 100. The wire 32 passes through the through hole of the main cooling component 100 and passes through the inner pipe 201.

[0113] When the cooling device 10 is operating, the cooling medium flows sequentially through the first nose cone cooling element 300 and the second nose cone cooling element 400 according to the series flow path described in the above embodiment, thereby removing the heat generated by the high-frequency loss and beam bombardment of the drift tube shell 20. Because the cooling medium flows forcibly and sequentially through the main cooling element 100, the first nose cone cooling element 300, and the second nose cone cooling element 400, with virtually no dead zones, the temperature distribution along the axial direction of the drift tube is more uniform, avoiding deformation of the shell 20 or a decrease in beam quality due to localized overheating. Simultaneously, the integrated three-layer pipe structure of the support element 200 reduces the number of external cooling pipes, making the overall structure of the drift tube compact and easy to install and maintain within the accelerator vacuum chamber.

[0114] It should be noted that the drift tube described in this embodiment is not limited to containing only two nose cone cooling elements. Depending on the length of the drift tube and the heat load distribution, multiple nose cone cooling elements can be arranged along the axial direction of the outer shell 20 tube body. The main cooling element 100 is correspondingly equipped with multiple reversing cavities, which are similar to the transition cavity 1022. The series cooling of each stage of the nose cone cooling elements can be achieved through multiple transition cooling elements.

[0115] In this embodiment, the drift tube achieves efficient and uniform cooling by integrating the drift tube double-layer cooling device 10 in the above embodiment; the series flow path ensures that each nose cone cooling component can obtain a sufficient flow of cooling medium, and there is no problem of uneven flow distribution caused by parallel connection; the support component 200 integrates the inlet and outlet channels of the cooling medium, eliminating the need for external hoses and improving the reliability of vacuum sealing; the drift tube double-layer cooling device 10 is highly integrated with the drift tube structure, which facilitates modular production and replacement.

[0116] To verify the cooling effect of the present invention, a simulation analysis was performed on the drift tube cooling device in the above embodiments. The simulation was based on the actual working conditions of the drift tube, including the heat load generated by high-frequency losses, the flow parameters of the cooling medium, and the geometry of the drift tube. A coupled fluid dynamics and thermodynamics analysis method was used to systematically evaluate the flow field distribution, temperature field distribution, and thermal deformation characteristics of the cooling device.

[0117] Flow field analysis shows that the series cooling flow path ensures a uniform velocity distribution of the cooling medium within the main cooling element 100, the first nose cone cooling element 300, and the second nose cone cooling element 400. The flow guiding structure effectively prevents short-circuiting between the inlet channel 204 and the outlet channel 205, ensuring the cooling medium flows sequentially through each cooling element according to the designed path, with no stagnant flow areas. The flow velocity within the nose cone cooling element's cavity meets the requirements for forced convection heat transfer. The baffle 105 divides the flow channel into a meandering, wavy shape, significantly extending the contact time between the cooling medium and the wall surface, enhancing turbulence intensity, and improving heat transfer efficiency.

[0118] Thermal field analysis shows that forced convection heat transfer effectively removes heat from the nose cone tip region, eliminating the localized hot spot phenomenon common in traditional solutions. The temperature distribution along the axial direction of the drift tube becomes more uniform, and the axial temperature gradient is significantly reduced. Compared with the traditional solution that only arranges cooling sleeves in the cylindrical section 22, this invention directly forces cooling of the nose cone region through the first nose cone cooling element 300 and the second nose cone cooling element 400, significantly reducing the maximum temperature at the nose cone tip and resulting in a more uniform overall temperature field distribution. This avoids the risk of material performance degradation and vacuum seal failure caused by localized overheating.

[0119] Thermal-structural coupling analysis shows that a uniform temperature field makes the thermal expansion of various parts of the drift tube tend to be consistent, effectively suppressing the damage to the precise geometry of the acceleration gap caused by differential thermal expansion. The thermal expansion of the nose cone tip is controlled within a safe range at the micrometer level, and the thermal drift of the acceleration cavity resonant frequency is significantly reduced. Simulation results verify that the cooling device of this invention can effectively solve the heat dissipation problem in the nose cone region of a drift tube with a nose cone. Through the design of an integrated sleeve structure, a series forced flow path, and the elimination of flow dead zones, uniform and efficient cooling of the entire drift tube, especially the critical area of ​​the nose cone, is achieved, ensuring the long-term stability of the high-frequency parameters of the acceleration cavity and providing strong support for the reliable operation of the drift tube under high power and high duty cycle conditions.

[0120] In one embodiment, a double-layer cooling method for a drift tube is provided, employing the double-layer cooling device 10 for the drift tube described in the above embodiment. The cooling method includes the following steps:

[0121] Start the cooling system and introduce the cooling medium from the external cooling system into the water inlet channel 204 of the support 200 through the water inlet pipe 206. That is, the cooling medium enters the annular channel between the inner layer pipe 201 and the middle layer pipe 202 and flows downward to the lower opening of the water inlet channel 204 and enters the inner ring cooling chamber 101 of the main cooling component 100.

[0122] After the cooling medium enters the inner ring cooling chamber 101, it flows along the annular channel of the inner ring cooling chamber 101 and around the inner wall of the main cooling component 100 at least once, under the guidance of the inner ring baffle strip 1011, and fully convects and exchanges heat with the inner wall of the main cooling component 100 to complete the first stage of cooling.

[0123] After the first stage of cooling is completed, all the cooling medium is gathered at the connecting port 103 and enters the first cavity 1021 of the outer ring cooling cavity 102 from the inner ring cooling cavity 101 through the connecting port 103, realizing the switching of the cooling flow path from the inner layer to the outer layer.

[0124] Guided by the outer ring baffle 1024, the cooling medium flows from the first cavity 1021 along the annular channel of the outer ring cooling cavity 102 in the direction away from the support member 200, and exchanges heat with the wall of the outer ring cooling cavity 102 to complete the cooling of the outer wall of the main cooling member 100.

[0125] After the cooling medium reaches the interface of the first cavity 1021, it enters the first nose cone cooling component 300 through the liquid inlet flow section 501 of the first adapter cooling component 500. It flows in a fixed direction in the internal channel of the first nose cone cooling component 300 and exchanges heat with the wall of the first nose cone cooling component 300 to directly cool the inner wall of the first nose cone section 21 of the drift tube.

[0126] After the cooling medium flows out of the first nose cone cooling component 300, it enters the transition cavity 1022 of the outer ring cooling cavity 102 through the liquid transfer part 502 of the first transition cooling component 500, thus completing the reversal of the cooling medium.

[0127] After the cooling medium flows in the transition cavity 1022, it enters the second nose cone cooling component 400 through the liquid inlet transfer section 501 of the second transfer cooling component 600. It flows in a fixed direction in the internal channel of the second nose cone cooling component 400 and exchanges heat with the wall of the second nose cone cooling component 400 to directly cool the inner wall of the second nose cone section 23 of the drift tube.

[0128] After the cooling medium flows out from the second nose cone cooling component 400, it enters the final cavity 1023 of the outer ring cooling cavity 102 through the liquid transfer section 502 of the second transition cooling component 600.

[0129] The cooling medium flows from the end chamber 1023 to the support member 200, flows upward through the water outlet channel 205 between the middle layer pipe 202 and the outer layer pipe 203, is discharged through the water outlet pipe 207, and returns to the external cooling system to complete a complete cooling cycle.

[0130] In the above cooling method, the cooling medium sequentially cools the inner ring cooling chamber 101 wall, the outer ring cooling chamber 102 wall, the first nose cone cooling component 300 wall, and the second nose cone cooling component 400 wall in series, forming a fully covered cooling flow path without dead zones. By controlling the flow rate of the cooling medium, the heat transfer intensity of each cooling zone can be adjusted, making the temperature distribution of the drift tube uniform along the axial and circumferential directions, avoiding thermal expansion deformation and high-frequency characteristic deviation caused by local overheating. The temperature of the cooling medium gradually increases along the flow path. By rationally designing the volume of each chamber and the cross-sectional area of ​​the flow channel, the flow velocity of the cooling medium in each cooling zone can be made basically equal, ensuring the uniformity and repeatability of the cooling effect.

[0131] While the principles herein have been illustrated in various embodiments, numerous modifications to the structures, arrangements, proportions, elements, materials, and components, particularly suited to specific environments and operational requirements, may be used without departing from the principles and scope of this disclosure. These modifications and other alterations or alterations will be included within the scope of this document. Those skilled in the art will recognize that many changes can be made to the details of the above embodiments without departing from the fundamental principles of the invention.

Claims

1. A drift tube double-layer cooling device, characterized in that, include: The main cooling component (100) has an inner ring cooling cavity (101) and an outer ring cooling cavity (102) along the thickness direction. The inner ring cooling cavity (101) and the outer ring cooling cavity (102) are connected by a communication port (103). A support member (200) is connected to the main cooling member (100), and the support member (200) has a water inlet channel (204) communicating with the inner ring cooling chamber (101) and a water outlet channel (205) communicating with the outer ring cooling chamber (102). At least one nose cone cooling element and a transition cooling element, the nose cone cooling element being disposed on one side of the main cooling element (100) and connected in series with the outer ring cooling cavity (102) through the transition cooling element; as well as A flow guiding structure is provided inside the main cooling component (100) to guide the cooling medium to flow sequentially through the inner ring cooling cavity (101) and the outer ring cooling cavity (102) along a predetermined path. The cooling medium flows sequentially through the following in the cooling device (10): the water inlet channel (204), the inner ring cooling chamber (101), the connecting port (103), the outer ring cooling chamber (102), the adapter cooling component, the nose cone cooling component, the adapter cooling component, the outer ring cooling chamber (102), and the water outlet channel (205), forming a series cooling flow path.

2. The drift tube double-layer cooling device as described in claim 1, characterized in that, The outer ring cooling chamber (102) is divided into a first chamber (1021), a transition chamber (1022) and a last chamber (1023), and the inner ring cooling chamber (101) is connected to the first chamber (1021) through the connecting port (103); The nose cone cooling component is provided in two sets, namely the first nose cone cooling component (300) and the second nose cone cooling component (400), which are respectively provided on both sides of the main cooling component (100); the adapter cooling component is provided in two sets, namely the first adapter cooling component (500) and the second adapter cooling component (600). The first transition cooling element (500) connects the first cavity (1021), the first nose cone cooling element (300), and the transition cavity (1022), and is configured to: introduce the cooling medium in the first cavity (1021) into the first nose cone cooling element (300), and then guide the cooling medium flowing out of the first nose cone cooling element (300) into the transition cavity (1022); the second transition cooling element (600) connects the transition cavity (1022), the second nose cone cooling element (400), and the final cavity (1023), and is configured to: introduce the cooling medium in the transition cavity (1022) into the second nose cone cooling element (400), and then guide the cooling medium flowing out of the second nose cone cooling element (400) into the final cavity (1023).

3. The drift tube double-layer cooling device as described in claim 2, characterized in that, The support member (200) includes an inner layer pipe (201), a middle layer pipe (202), and an outer layer pipe (203) arranged coaxially. The water inlet channel (204) is formed between the inner layer pipe (201) and the middle layer pipe (202), and the water inlet channel (204) is connected to the inner ring cooling chamber (101). The water outlet channel (205) is formed between the middle layer pipe (202) and the outer layer pipe (203), and the water outlet channel (205) is connected to the outer ring cooling chamber (102). The cooling medium flows sequentially through the following components in the cooling device (10): the water inlet channel (204), the inner ring cooling chamber (101), the first chamber (1021), the first transition cooling component (500), the first nose cone cooling component (300), the first transition cooling component (500), the transition chamber (1022), the second transition cooling component (600), the second nose cone cooling component (400), the second transition cooling component (600), the final chamber (1023), and the water outlet channel (205), forming a series cooling flow path.

4. The drift tube double-layer cooling device as described in claim 1, characterized in that, The main cooling component (100), the first nose cone cooling component (300), and the second nose cone cooling component (400) are all configured as sleeve structures. The inner ring cooling cavity (101) and the outer ring cooling cavity (102) are both arranged in annular channels. The shape of the main cooling component (100), the first nose cone cooling component (300), and the second nose cone cooling component (400) matches the shape of the inner wall of the drift tube.

5. The drift tube double-layer cooling device as described in claim 2, characterized in that, The flow guiding structure includes an inner ring baffle (1011), which is disposed in the inner ring cooling cavity (101) and located between the connecting port (103) and the support member (200) to guide the cooling medium to flow along the annular channel of the inner ring cooling cavity (101) to the connecting port (103).

6. The drift tube double-layer cooling device as described in claim 5, characterized in that, The flow guiding structure also includes an outer ring liquid baffle (1024), which is disposed in the outer ring cooling cavity (102) and located between the connecting port (103) and the support member (200) to isolate the first cavity (1021) and the last cavity (1023) and guide the cooling medium to flow to the water outlet channel (205).

7. The drift tube double-layer cooling device as described in claim 6, characterized in that, The inner ring baffle (1011) and the outer ring baffle (1024) are arranged radially overlapping along the main cooling component (100), and the connecting port (103), the inner ring baffle (1011) and the outer ring baffle (1024) are all located close to the support component (200).

8. The drift tube double-layer cooling device according to any one of claims 1-7, characterized in that, The main cooling component (100), the first nose cone cooling component (300) and the second nose cone cooling component (400) are provided with a number of baffles (105) in the water path of the inner cavity to divide the cooling medium channel into a number of sequentially connected flow units, and the channel openings (1051) of two adjacent baffles (105) are set far apart from each other to extend the path length of the cooling medium.

9. A drift tube, characterized in that, include: The outer shell (20) includes a first nasal cone segment (21), a cylindrical segment (22), and a second nasal cone segment (23) arranged sequentially. The drift tube double-layer cooling device (10) as described in any one of claims 1-8 is disposed inside the outer shell (20); wherein the shape of the nose cone cooling component matches the inner wall of the first nose cone segment (21) and the second nose cone segment (23), and the shape of the main cooling component (100) matches the inner wall of the cylindrical segment (22); A coil assembly (30) comprising a coil portion (31) and a conductor (32), the coil portion (31) being disposed within the cavity of the cylindrical section (22), and the conductor (32) being arranged through the support member (200); and The core tube (40) is coaxially arranged at the center of the coil section (31) and passes through both ends of the outer casing (20).

10. A double-layer cooling method for a drift tube, characterized in that, The drift tube double-layer cooling device as described in any one of claims 1-8 includes the following steps: Cooling medium is introduced into the drift tube cooling device (10) from the water inlet channel (204) of the support (200), and the drift tube cooling device (10) is located inside the drift tube and matches the inner wall of the drift tube; The cooling medium enters the inner ring cooling chamber (101) of the main cooling component (100) and flows along the annular channel of the inner ring cooling chamber (101) for at least one complete cycle under the guidance of the flow guiding structure; The cooling medium enters the outer ring cooling chamber (102) through the connecting port (103); The cooling medium flows sequentially through the outer ring cooling chamber (102), the adapter cooling component, and the nose cone cooling component, and then returns from the adapter cooling component to the outer ring cooling chamber (102). The cooling medium is discharged from the water outlet channel (205).

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