A direct cooling structure and method for the anode of an X-ray tube

Abstract

This invention discloses a direct cooling structure and method for the anode of an X-ray tube, relating to the field of X-ray tube cooling technology. It includes an anode and a cathode, as well as an externally encased X-ray tube shell. The anode includes a copper column and a metal target. A groove is provided on the right side of the copper column, and the metal target is welded into the groove. A filament is provided at the front end of the cathode, which is fixedly disposed inside the right side of the X-ray tube shell. The front end of the copper column and the metal target are located inside the X-ray tube shell, while the rear end of the copper column is located outside the X-ray tube shell and fixed to it. An inlet channel and an outlet channel are provided inside the copper column. A manifold distribution channel is provided on the right side of the copper column, connecting to the inlet and outlet channels. A heat dissipation microchannel is provided on the left side of the metal target, connecting to the manifold distribution channel.

Description

Technical Field

[0001] This invention relates to the field of X-ray tube cooling technology, specifically to a direct anode cooling structure and method for X-ray tubes. Background Technology

[0002] X-ray inspection equipment is widely used in medical, industrial non-destructive testing, and other fields. Its core component is the X-ray tube, which emits X-rays. The X-ray tube generates X-rays by accelerating electrons and causing them to collide with a target material (usually a metal target, such as molybdenum or copper) on the anode. During the collision, electrons are converted into X-rays, but most of the energy is released as heat; typically, about 99% of the electrical energy is converted into heat, and less than 1% is converted into X-rays. Excessive anode temperature can lead to deformation or even damage, thus affecting the imaging quality of the X-ray tube. The target surface temperature is the most significant, usually appearing as hot spots, requiring sophisticated heat dissipation design to ensure effective cooling.

[0003] For overall heat dissipation of X-ray tubes, a common method is liquid cooling, typically using oil as the cooling medium to encapsulate the entire tube. The oil not only absorbs heat but also provides insulation to prevent electrical leakage. As the tube temperature rises, a circulating oil cooling system outside the tube drives the low-temperature oil medium to flow and remove heat. This requires a specially designed oil pump and cooling device to maintain oil flow and temperature control. For high-power X-ray tubes, conventional cooling structures are insufficient, necessitating larger cooling structures. However, portability is a crucial characteristic of some X-ray detection equipment, leaving no space for larger cooling structures. Therefore, there is an urgent need to research a compact and highly efficient X-ray tube cooling structure. Summary of the Invention

[0004] The purpose of this invention is to solve the problems mentioned in the background art, and thus proposes a direct cooling structure and method for X-ray tube anodes. The structure disclosed in this invention expands the heat dissipation area of ​​the anode hotspot region by setting up heat dissipation microchannels, accelerating heat conversion and improving cooling efficiency; by setting up manifold distribution channels, the coolant is evenly distributed, improving the overall cooling effect of the structure, enhancing the temperature uniformity of the entire target surface, and preventing the occurrence of local hotspots; the tortuous channels within the manifold distribution channels and heat dissipation microchannels increase fluid disturbance, reduce the occurrence of the thermal boundary layer between the fluid and solid, and the liquid working fluid flowing from the manifold channels impacts the microchannel structure from top to bottom, further enhancing the heat transfer effect. Simultaneously, the structure disclosed in this invention is an optimized design based on the original X-ray tube anode structure, requiring minimal modification to the original X-ray tube structure, resulting in a small overall cooling structure volume, facilitating the integration of the entire device, and contributing to the miniaturization and portability of X-ray equipment.

[0005] The technical solution adopted by this invention to solve its technical problem is:

[0006] A direct anode cooling structure for an X-ray tube includes an anode and a cathode, as well as an external X-ray tube shell. The anode includes a copper column and a metal target. A groove is provided on the right side of the copper column, and the metal target is welded into the groove of the copper column. A filament is provided at the front end of the cathode, which is fixedly disposed inside the right side of the X-ray tube shell. The front end of the copper column and the metal target are located inside the X-ray tube shell, and the rear end of the copper column is located outside the X-ray tube shell and fixed to it. An inlet channel and an outlet channel are provided inside the copper column. A manifold distribution channel is provided on the right side of the copper column, and the manifold distribution channel is connected to the inlet and outlet channels. A heat dissipation microchannel is provided on the left side of the metal target, and the heat dissipation microchannel is connected to the manifold distribution channel.

[0007] Preferably, a coolant circulation assembly is provided outside the copper column. The coolant circulation assembly includes a circulation pump, a coolant storage tank, and a pipeline. The pipeline connects the circulation pump and the coolant storage tank in series. The speed of the circulation pump is adjustable. An inlet is provided outside the inlet channel, and an outlet is provided outside the outlet channel. One end of the pipeline is connected to the inlet, and the other end of the pipeline is connected to the outlet.

[0008] Preferably, a heat exchanger is installed on the pipeline, the heat exchanger is located on the pipeline between the liquid outlet and the coolant storage tank, and a heat exchange fan is installed on the outside of the heat exchanger, the speed of the heat exchange fan being adjustable.

[0009] Preferably, temperature sensors are provided at the inlet and outlet. The structure disclosed in this invention also includes a control terminal, which is electrically connected to the circulating pump, the heat exchange fan and the temperature sensors.

[0010] Preferably, the rated flow rate Q (g / s) of the coolant in the pipeline is calculated using the following formula:

[0011] Q = C p (TT e )

[0012] Where: C P T is the specific heat of the coolant at atmospheric pressure, and T is the normal operating temperature of the metal target. e This refers to the ambient temperature, i.e., the natural temperature of the coolant.

[0013] Preferably, the width W of the heat dissipation microchannel is in the range of 200Qμm to 500Qμm, and the depth D of the heat dissipation microchannel is in the range of 1000Qμm to 2000Qμm.

[0014] Preferably, the width W of the manifold diversion channel mThe depth D of the manifold distribution channel is twice the width W of the heat dissipation microchannel. m The depth D of the heat dissipation microchannel is 4 times that of the heat dissipation microchannel.

[0015] A method for direct cooling of the anode of an X-ray tube includes the following steps:

[0016] S1. Install the cooling structure;

[0017] S2. The cooling system starts operating, and the temperature sensor at the liquid outlet detects a temperature of T. out , such as T out -T≤10℃, the equipment is operating normally, such as T out When T > 10℃, the control terminal increases the speed of the circulating pump until T... out -T≤10℃, if T out If the speed cannot be reduced, the control terminal will increase the speed of the heat exchange fan.

[0018] S3, The temperature sensor at the liquid inlet detects the temperature as T. in , such as T in <T e The equipment is operating normally, such as T. in >T e The control terminal controls the heat exchange fan to increase its speed until T in <T e , if T in If the speed cannot be reduced, the control terminal will increase the rotation speed of the circulating pump.

[0019] S4. When the X-ray tube is running for an extended period of time, the temperature sensor at the inlet detects a temperature of T. in Unable to drop to T e The control terminal then determines that the X-ray tube is overloaded and needs to be shut down for a break. At this time, the cooling system continues to operate. in -T e When the temperature is above 10℃, the control terminal determines that the X-ray tube can continue to work.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] 1. The structure disclosed in this invention expands the heat dissipation area of ​​the anode hotspot region by setting up heat dissipation microchannels, accelerating heat conversion and improving cooling efficiency; by setting up manifold distribution channels, the coolant is evenly distributed, improving the overall cooling effect of the structure, enhancing the temperature uniformity of the entire target surface, and preventing the formation of local hotspots; the tortuous channels within the manifold distribution channels and heat dissipation microchannels increase fluid disturbance, reduce the formation of the thermal boundary layer between the fluid and solid, and the liquid working fluid flowing out of the manifold channels impacts the microchannel structure from top to bottom, further enhancing the heat transfer effect. Furthermore, the structure disclosed in this invention is an optimized design based on the original X-ray tube anode structure, requiring minimal modification to the original X-ray tube structure, resulting in a small overall cooling structure volume, facilitating the integration of the entire device, and contributing to the miniaturization and portability of X-ray equipment.

[0022] 2. The structure disclosed in this invention is based on the original structure of the X-ray tube anode and is optimized. The original structure of the X-ray tube is modified less, the volume of the entire cooling structure is small, and it is easy to integrate the whole equipment, which helps the X-ray equipment to develop towards miniaturization and portability.

[0023] 3. The structure disclosed in this invention cools the coolant after heat absorption by means of air cooling, and improves the flexibility of the cooling structure by controlling the speed of the circulating pump and heat exchange fan by means of a control terminal.

[0024] 4. The width and depth of the manifold distribution channel and heat dissipation microchannel in the structure disclosed in this invention have been obtained through simulation calculation and analysis, resulting in the optimal proportional relationship between the parameters, thus maximizing the cooling effect of the structure.

[0025] 5. The structure disclosed in this invention detects the temperature of the liquid inlet and outlet using a temperature sensor, and changes the structure's operating mode through a control terminal, thereby improving the stability of the cooling structure, reducing the risk of X-ray tube damage, indirectly reducing costs, and improving the safety of equipment use. Attached Figure Description

[0026] Figure 1 This is a cross-sectional view of the structure disclosed in this invention;

[0027] Figure 2 This is a schematic diagram of the cooling operation principle of the structure disclosed in this invention;

[0028] Figure 3 This is an isometric drawing of the structure disclosed in this invention;

[0029] Figure 4 This is a schematic diagram showing the anode component arrangement of the structure disclosed in this invention;

[0030] Figure 5 This is a schematic diagram of the back structure of the metal target disclosed in this invention;

[0031] Figure 6The coolant flow process within the manifold distribution channel of the structure disclosed in this invention is described.

[0032] The components include: 1. Anode; 2. Metal target; 3. Copper column; 4. Cathode; 5. Filament; 6. X-ray tube housing; 7. Manifold distribution channel; 8. Liquid inlet channel; 9. Liquid outlet channel; 10. Liquid inlet; 11. Liquid outlet; 12. Heat dissipation microchannel; 13. Circulation pump; 14. Heat exchanger; 15. Heat exchange fan; 16. Coolant storage tank; 17. Piping. Detailed Implementation

[0033] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0034] Example 1, as Figure 1 - Figure 6 As shown, an X-ray tube anode direct cooling structure includes an anode component 1, a cathode component 4, and an externally encased X-ray tube shell 6. The anode component 1 includes a copper pillar 3 and a metal target 2. A groove is provided on the right side of the copper pillar 3, and the metal target 2 is welded into the groove of the copper pillar 3. A filament 5 is provided at the front end of the cathode component 4, and the cathode component 4 is fixedly disposed inside the right side of the X-ray tube shell 6. The front end of the copper pillar 3 and the metal target 2 are located inside the X-ray tube shell 6, and the rear end of the copper pillar 3 is located outside the X-ray tube shell 6 and is fixed to the X-ray tube shell 6. The copper pillar 3 is provided with an inlet channel 8 and an outlet channel 9. A manifold distribution channel 7 is provided on the right side of the copper pillar 3. The manifold distribution channel 7 is connected to the inlet channel 8 and the outlet channel 9. The route in the manifold distribution channel 7 is tortuous, which increases the flow distance of the coolant. A heat dissipation microchannel 12 is provided on the left side of the metal target 2. The heat dissipation microchannel 12 increases the heat exchange area between the coolant and the metal target 2. The heat dissipation microchannel 12 is connected to the manifold distribution channel 7, which makes the coolant distribution more uniform and avoids local hot spots from being not cooled properly, thus preventing damage to the metal target 2.

[0035] like Figure 2As shown, a coolant circulation assembly is installed outside the copper column 3. The coolant circulation assembly includes a circulation pump 13, a coolant storage tank 16, and a pipe 17. The pipe 17 connects the circulation pump 13 and the coolant storage tank 16 in series. The speed of the circulation pump 13 is adjustable. By adjusting the speed of the circulation pump 13, the rated flow rate Q of the coolant can be changed to adapt to the cooling requirements of the metal target 2 under different conditions. An inlet 10 is provided outside the inlet channel 8, and an outlet 11 is provided outside the outlet channel 9. One end of the pipe 17 is connected to the inlet 10, and the other end of the pipe 17 is connected to the outlet 11. A heat exchanger 14 is installed on the pipe 17, and the heat exchanger 14 is located between the outlet 11 and the coolant storage tank 16. On the pipe 17, a heat exchange fan 15 is installed on the outside of the heat exchanger 14. The structure disclosed in this invention operates by air-cooled heat exchange. The speed of the heat exchange fan 15 is adjustable. By adjusting the speed of the heat exchange fan 15, the temperature of the coolant at the outlet 11 of the equipment is changed to ensure that the equipment can operate normally. Temperature sensors are installed at the inlet 10 and the outlet 11 to monitor the temperature of the coolant at the inlet 10 and the outlet 11, so that the control terminal can change the operating mode to adapt to the heat dissipation requirements of the X-ray tube under different conditions. The structure disclosed in this invention also includes a control terminal, which is electrically connected to the circulating pump 13, the heat exchange fan 15 and the temperature sensors to realize the intelligent operation of the cooling structure.

[0036] like Figure 6 The diagram illustrates the coolant flow process within the manifold distribution channel of the structure disclosed in this invention. The distribution channels within the manifold distribution channel 7 and the heat dissipation microchannels 12 are perpendicular to each other. The manifold distribution channel 7 is connected to both the inlet channel 8 and the outlet channel 9. The distribution channels within the manifold distribution channel 7 are divided into two types: the inlet channel connected to the inlet channel 8 and the outlet channel connected to the outlet channel 9. Coolant enters the inlet channel of the manifold distribution channel 7 from the inlet channel 8. Because the distribution channels within the manifold distribution channel 7 and the heat dissipation microchannels 12 are perpendicular to each other, the coolant flows towards the heat dissipation microchannels 12. After the heat dissipation microchannels 12 are filled, under the action of hydraulic pressure, the coolant in the heat dissipation microchannels 12 flows towards the outlet channel of the manifold distribution channel 7, and finally flows out from the outlet channel 9.

[0037] In Example 2, the optimal dimensions of the heat dissipation microchannel 12 and the manifold distribution channel 7 were calculated using finite element method (FEM) simulation to achieve optimal temperature uniformity and maximum coefficient of performance (COP) of the cooling structure. The rated flow rate Q (g / s) of the coolant in the pipe 17 is calculated using the following formula:

[0038] Q = C p (TT e )

[0039] Where: C PT is the specific heat of the coolant at atmospheric pressure, and T is the normal operating temperature of the metal target 2. e This refers to the ambient temperature, i.e., the natural temperature of the coolant.

[0040] The width W of the heat dissipation microchannel 12 ranges from 200Qμm to 500Qμm, and the depth D of the heat dissipation microchannel 12 ranges from 1000Qμm to 2000Qμm. The spacing between adjacent channels is the same as the width W of the heat dissipation microchannel 12. This size provides the maximum cooling capacity and simplifies the manufacturing process.

[0041] Based on calculation and analysis, the depth D of the manifold diversion channel 7 is... m It primarily affects the uniformity of coolant distribution in each channel of the heat dissipation microchannel 12, and the depth D of the manifold distribution channel 7. m The larger the diameter, the more uniform the coolant flow distribution in the multiple microchannels below, and the better the temperature uniformity at the metal target 2 surface; the width W of the manifold distribution channel 7 m This primarily affects the cooling performance within the heat dissipation microchannel 12 below it, and the width W of the manifold distribution channel 7. m The smaller the diameter, the longer the flow distance of the coolant within the heat dissipation microchannel 12, and the stronger the cooling capacity of the coolant on the metal target 2. Therefore, the width W of the manifold distribution channel 7 is... m The depth D of the manifold distribution channel 7 is twice the width W of the heat dissipation microchannel 12. m The depth D of the heat dissipation microchannel 12 is 4 times that of the cooling structure that combines the manifold distribution channel 7 and the heat dissipation microchannel 12, which can achieve the best temperature uniformity and the highest energy efficiency ratio (COP).

[0042] A method for direct cooling of the anode of an X-ray tube includes the following steps:

[0043] S1. Install the cooling structure;

[0044] S2. The cooling structure starts operating, and the temperature sensor installed at outlet 11 detects a temperature of T. out , such as T out -T≤10℃, the equipment is operating normally, such as T out When T > 10℃, the control terminal controls the circulation pump 13 to increase its speed until T... out -T≤10℃, if T out If the speed cannot be reduced, the control terminal controls the heat exchange fan 15 to increase its speed.

[0045] S3, The temperature sensor at the liquid inlet 10 detects a temperature of T. in , such as T in <T e The equipment is operating normally, such as T. in >T eThe control terminal controls the heat exchange fan 15 to increase its speed until T in <T e , if T in If the speed cannot be reduced, the control terminal controls the circulation pump 13 to increase its speed.

[0046] S4. When the X-ray tube is running for an extended period of time, the temperature sensor at the inlet 10 detects a temperature of T. in Unable to drop to T e The control terminal then determines that the X-ray tube is overloaded and needs to be shut down for a break. At this time, the cooling system continues to operate. in -T e When the temperature is above 10℃, the control terminal determines that the X-ray tube can continue to work.

[0047] The coolant is an electronic fluorinated liquid, which has a low boiling point and low viscosity, reducing the flow resistance of the coolant in the heat dissipation microchannel 12, and can be effectively converted from liquid to vapor, utilizing the latent heat of vaporization of the liquid to improve the cooling capacity of the cooling structure.

[0048] In the description of this invention, the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "vertical," and "horizontal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only to describe the invention and not to require the invention to be constructed or operated in a specific orientation; therefore, they should not be construed as limitations on the invention. The terms "connected" and "linked" in this invention should be interpreted broadly. For example, they can refer to a connection or a detachable connection; they can refer to a direct connection or an indirect connection through intermediate components. Those skilled in the art can understand the specific meaning of the above terms based on the specific circumstances.

[0049] The above description represents the preferred mode of operation of the present invention. The specific operational modes are provided solely for a better understanding of the invention's concept. Those skilled in the art can make various improvements or equivalent substitutions based on the principles of this invention, and these improvements or equivalent substitutions are also considered to fall within the scope of protection of this invention.

Claims

1. A direct anode cooling structure for an X-ray tube, comprising an anode (1) and a cathode (4), and an externally encased X-ray tube shell (6), characterized in that, The anode component (1) includes a copper column (3) and a metal target (2). A groove is provided on the right side of the copper column (3), and the metal target (2) is welded into the groove of the copper column (3). A filament (5) is provided at the front end of the cathode component (4). The cathode component (4) is fixedly installed inside the right side of the X-ray tube shell (6). The front end of the copper column (3) and the metal target (2) are located inside the X-ray tube shell (6). The rear end of the copper column (3) is located outside the X-ray tube shell (6) and is fixed to the X-ray tube shell (6). An inlet channel (8) and an outlet channel (9) are provided inside the copper column (3). A manifold distribution channel (7) is provided on the right side, which is connected to the inlet channel (8) and the outlet channel (9). A heat dissipation microchannel (12) is provided on the left side of the metal target (2), which is connected to the manifold distribution channel (7). The branch channels inside the manifold distribution channel (7) and the heat dissipation microchannel (12) are perpendicular to each other. The coolant flows to the heat dissipation microchannel (12). After the heat dissipation microchannel (12) is filled, under the action of hydraulic pressure, the coolant in the heat dissipation microchannel (12) flows to the outlet branch channel of the manifold distribution channel (7). The width W of the manifold distribution channel (7) is... m The depth D of the manifold distribution channel (7) is twice the width W of the heat dissipation microchannel (12). m It is 4 times the depth D of the heat dissipation microchannel (12).

2. The X-ray tube anode direct cooling structure according to claim 1, characterized in that, A coolant circulation assembly is provided outside the copper column (3). The coolant circulation assembly includes a circulation pump (13), a coolant storage tank (16), and a pipe (17). The pipe (17) is connected in series with the circulation pump (13) and the coolant storage tank (16). The speed of the circulation pump (13) is adjustable. An inlet (10) is provided outside the inlet channel (8), and an outlet (11) is provided outside the outlet channel (9). One end of the pipe (17) is connected to the inlet (10), and the other end of the pipe (17) is connected to the outlet (11).

3. The X-ray tube anode direct cooling structure according to claim 2, characterized in that, A heat exchanger (14) is installed on the pipe (17). The heat exchanger (14) is located on the pipe (17) between the liquid outlet (11) and the coolant storage tank (16). A heat exchange fan (15) is installed on the outside of the heat exchanger (14). The speed of the heat exchange fan (15) is adjustable.

4. The X-ray tube anode direct cooling structure according to claim 3, characterized in that, Temperature sensors are provided at the liquid inlet (10) and liquid outlet (11). The cooling structure also includes a control terminal, which is electrically connected to the circulating pump (13), the heat exchange fan (15) and the temperature sensors.

5. The X-ray tube anode direct cooling structure according to claim 3, characterized in that, The rated flow rate Q (g / s) of the coolant in the pipe (17) is calculated using the following formula: Where: C P T is the specific heat of the coolant at atmospheric pressure, and T is the normal operating temperature of the metal target (2). e This refers to the ambient temperature, i.e., the natural temperature of the coolant.

6. The X-ray tube anode direct cooling structure according to claim 5, characterized in that, The width W of the heat dissipation microchannel (12) ranges from 200Qμm to 500Qμm, and the depth D of the heat dissipation microchannel (12) ranges from 1000Qμm to 2000Qμm. The spacing between adjacent channels is the same as the width W of the heat dissipation microchannel (12).

7. The cooling method for a direct cooling structure for an X-ray tube anode according to any one of claims 1-6, characterized in that, Includes the following steps: S1. Install the cooling structure; S2. The cooling structure starts operating, and the temperature sensor installed at the liquid outlet (11) detects a temperature of T. out , such as T out -T≤10℃, the equipment is operating normally, such as T out -T>10℃, control terminal control circulation pump (13) increases speed until T out -T≤10℃, if T out If the speed cannot be reduced, the control terminal controls the heat exchange fan (15) to increase its speed; S3, the temperature sensor at the liquid inlet (10) detects a temperature of T. in , such as T in <T e The equipment is operating normally, such as T. in >T e The control terminal controls the heat exchange fan (15) to increase its speed until T in <T e If T in If the speed cannot be reduced, the control terminal controls the circulating pump (13) to increase the speed; S4. When the X-ray tube is running for a long time, the temperature sensor at the liquid inlet (10) detects a temperature of T. in Unable to drop to T e The control terminal then determines that the X-ray tube is overloaded and needs to be shut down for a break. At this time, the cooling system continues to operate. in -T e When the temperature is above 10℃, the control terminal determines that the X-ray tube can continue to work.

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