X-ray tube anode direct cooling structure and method

Abstract

The invention discloses an X-ray tube anode direct cooling structure and method, and relates to the technical field of X-ray tube cooling, the X-ray tube anode direct cooling structure comprises an anode piece, a cathode piece and an X-ray tube shell wrapped outside, the anode piece comprises a copper column and a metal target, the right side of the copper column is provided with a groove, the metal target is welded in the groove of the copper column, and the metal target is welded in the groove of the copper column. A filament is arranged at the front end of the cathode piece, the cathode piece is fixedly arranged on the right side in the X-ray tube shell, the front end of the copper column and the metal target are located in the X-ray tube shell, the rear end of the copper column is located outside the X-ray tube shell and fixed to the X-ray tube shell, and a liquid inlet channel and a liquid outlet channel are formed in the copper column. The right side of the copper column is provided with a manifold shunting channel, the manifold shunting channel is connected with the liquid inlet channel and the liquid outlet channel, the left side of the metal target is provided with a heat dissipation micro-channel, and the heat dissipation micro-channel is connected with the manifold shunting channel.

Description

Technical Field

[0001] The present invention relates to the technical field of X-ray tube cooling, and in particular to a direct cooling structure and method for an anode of an X-ray tube. Background Art

[0002] X-ray inspection equipment is widely used in the fields of medical treatment, industrial non-destructive testing, etc. Its core component is the X-ray tube that emits X-rays. The X-ray tube generates X-rays by accelerating electrons and making them collide with the target material on the anode (usually a metal target, such as molybdenum, copper, etc.). Electrons are converted into X-rays during the collision, but most of the energy is released in the form of heat, usually about 99% of the electrical energy is converted into heat, and less than 1% of the electrical energy is converted into X-rays. Excessive temperature of the anode may cause it to deform or even damage, which in turn affects the imaging quality of the X-ray tube. Among them, the target surface temperature is the most significant, usually appearing in the form of hot spots, and requires sophisticated heat dissipation design to ensure its effective cooling.

[0003] For the heat dissipation of the X-ray tube as a whole, a common heat dissipation method is to use liquid cooling, usually using oil as a cooling medium to wrap the entire X-ray tube. The oil can not only absorb the heat of the tube but also insulate to prevent leakage. When the temperature of the tube rises, the circulating oil cooling system outside the X-ray tube drives the low-temperature oil working medium to flow outside the tube to take away the heat. A specially designed oil pump and oil cooling device are required to maintain the flow of the oil and temperature control. For high-power X-ray tubes, conventional cooling structures cannot achieve the cooling effect and need to increase the size of the cooling structure. However, portability is an important feature of some X-ray detection equipment, and there is no space to set up a larger cooling structure. Therefore, it is urgent to study a small-sized and high-cooling-efficiency X-ray tube cooling structure. Summary of the invention

[0004] The purpose of the present invention is to solve the problems raised in the above-mentioned background technology, and then propose a direct cooling structure and method for the anode of an X-ray tube. The structure disclosed in the present invention expands the heat dissipation area of ​​the hot spot area of ​​the anode part by setting a heat dissipation microchannel, accelerates heat conversion, and improves cooling efficiency; by setting a manifold shunt channel, the coolant is evenly distributed, the cooling effect of the entire structure is improved, the uniformity of the temperature of the entire target surface is improved, and the occurrence of local hot spots is prevented; the manifold shunt channel and the tortuous channels in the heat dissipation microchannel increase the disturbance of the fluid, reduce the occurrence of the thermal boundary layer between the fluid and the solid, and the liquid working fluid flowing out of the manifold channel impacts the microchannel structure from top to bottom, further enhancing the heat exchange effect. At the same time, the structure disclosed in the present invention is optimized based on the original structure of the anode of the X-ray tube, and the original structure of the X-ray tube is slightly modified. The volume of the entire cooling structure is small, and it is easy to integrate the entire equipment, which is conducive to the development of X-ray equipment towards miniaturization and portability.

[0005] The technical solution adopted by the present invention to solve the technical problem is:

[0006] An X-ray tube anode direct cooling structure comprises an anode component and a cathode component, and an X-ray tube shell wrapped externally, wherein the anode component comprises a copper column and a metal target, a groove is arranged on the right side of the copper column, and the metal target is welded in the groove of the copper column, a filament is arranged at the front end of the cathode component, and the cathode component is fixedly arranged on the right side inside the X-ray tube shell, the front end of the copper column and the metal target are located inside the X-ray tube shell, the rear end of the copper column is located outside the X-ray tube shell and is fixed to the X-ray tube shell, a liquid inlet channel and a liquid outlet channel are arranged inside the copper column, a manifold shunt channel is arranged on the right side of the copper column, and the manifold shunt channel is connected to the liquid inlet channel and the liquid outlet channel, a heat dissipation microchannel is arranged on the left side of the metal target, and the heat dissipation microchannel is connected to the manifold shunt channel.

[0007] Preferably, a coolant circulation component is arranged outside the copper column, and the coolant circulation component includes a circulation pump, a coolant storage tank and a pipeline. The pipeline is connected in series with the circulation pump and the coolant storage tank. The speed of the circulation pump is adjustable. A liquid inlet is arranged outside the liquid inlet channel, and a liquid outlet is arranged outside the liquid outlet channel. One end of the pipeline is connected to the liquid inlet, and the other end of the pipeline is connected to the liquid outlet.

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

[0009] Preferably, temperature sensors are provided at the liquid inlet and the liquid outlet. The structure disclosed in the present invention further comprises a control terminal, which is electrically connected to the circulation pump, the heat exchange fan and the temperature sensor.

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

[0011] Q=C p (TT e )

[0012] Where: C P is the specific heat of the coolant at normal pressure, T is the normal operating temperature of the metal target, T e is 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 is mThe depth D of the manifold diversion channel is twice the width W of the heat dissipation microchannel. m 4 times the depth D of the heat dissipation microchannel.

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

[0016] S1. Install the cooling structure;

[0017] S2, the cooling structure starts to operate, and the temperature sensor set at the outlet detects the temperature T out , such as T out -T≤10℃, the equipment operates normally, such as T out -T>10℃, the control terminal controls the circulation pump to increase the speed until T out -T≤10℃, if T out If the temperature cannot be lowered, the control terminal controls the heat exchange fan to speed up;

[0018] S3, the temperature sensor at the liquid inlet detects the temperature as T in , such as T in <T e , the equipment is running normally, such as T in >T e , the control terminal controls the heat exchange fan to speed up until T in <T e , if T in If the speed cannot be reduced, the control terminal controls the circulation pump to increase the speed;

[0019] S4. When the X-ray tube is running for a long time, the temperature sensor at the liquid inlet detects a temperature of T in Unable to drop to T e Next, the control terminal determines that the X-ray tube is overloaded and needs to be shut down for a rest. At this time, the cooling structure continues to work. in -T e When the temperature is higher than 10℃, the control terminal determines that the X-ray tube can continue to work.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The structure disclosed in the present invention expands the heat dissipation area of ​​the hot spot area of ​​the anode part by setting up a heat dissipation microchannel, accelerates heat conversion, and improves cooling efficiency; by setting up a manifold shunt channel, the coolant is evenly distributed, the cooling effect of the entire structure is improved, the uniformity of the temperature of the entire target surface is improved, and the appearance of local hot spots is prevented; the manifold shunt channel and the tortuous channels in the heat dissipation microchannel increase the disturbance of the fluid, reduce the appearance of the thermal boundary layer between the fluid and the solid, and the liquid working fluid flowing out of the manifold channel impacts the microchannel structure from top to bottom, further enhancing the heat exchange effect. At the same time, the structure disclosed in the present invention is optimized based on the original structure of the X-ray tube anode, and the original structure of the X-ray tube is slightly modified. The volume of the entire cooling structure is small, and it is easy to integrate the entire device, which is conducive to the development of X-ray equipment towards miniaturization and portability.

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

[0023] 3. The structure disclosed in the present invention cools down the cooling liquid after absorbing heat by means of air cooling, and controls the rotation speed of the circulation pump and the heat exchange fan by the control terminal, thereby improving the working flexibility of the cooling structure.

[0024] 4. The width and depth of the manifold shunt channel and the heat dissipation microchannel of the structure disclosed by the present invention are analyzed through simulation calculation, and the optimal proportional relationship between the parameters is obtained, so that the cooling effect of the structure is optimized.

[0025] 5. The structure disclosed by the present invention detects the temperature of the liquid inlet and the liquid outlet through a temperature sensor, and changes the operation mode of the structure through a control terminal, thereby improving the stability of the cooling structure, reducing the risk of damage to the X-ray tube, indirectly reducing costs and improving the safety of equipment use. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

[0028] Figure 3 An isometric view of the structure disclosed in the present invention;

[0029] Figure 4 A schematic diagram of the arrangement of the anode member of the structure disclosed in the present invention;

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

[0031] Figure 6The coolant flow process in the manifold shunt channel of the structure disclosed by the present invention.

[0032] Among them: 1. Anode; 2. Metal target; 3. Copper column; 4. Cathode; 5. Filament; 6. X-ray tube housing; 7. Manifold shunt 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. Pipeline. DETAILED DESCRIPTION

[0033] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0034] Embodiment 1, as Figure 1 - Figure 6 As shown, an X-ray tube anode direct cooling structure includes an anode component 1 and a cathode component 4, and an X-ray tube housing 6 wrapped externally, wherein the anode component 1 includes a copper column 3 and a metal target 2, a groove is arranged on the right side of the copper column 3, and the metal target 2 is welded in the groove of the copper column 3, a filament 5 is arranged at the front end of the cathode component 4, and the cathode component 4 is fixedly arranged on the right side inside the X-ray tube housing 6, the front end of the copper column 3 and the metal target 2 are located inside the X-ray tube housing 6, and the rear end of the copper column 3 is located outside the X-ray tube housing 6 and is fixed to the X-ray tube housing 6 A liquid inlet channel 8 and a liquid outlet channel 9 are arranged in the copper column 3, a manifold shunt channel 7 is arranged on the right side of the copper column 3, the manifold shunt channel 7 is connected with the liquid inlet channel 8 and the liquid outlet channel 9, the route in the manifold shunt channel 7 is tortuous, which increases the flow distance of the coolant, and a heat dissipation microchannel 12 is arranged 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 with the manifold shunt channel 7, the coolant is distributed more evenly, and the local hot spots are prevented from being cooled inadequately and damaging the metal target 2.

[0035] like Figure 2As shown, a coolant circulation component is arranged outside the copper column 3, and the coolant circulation component includes a circulation pump 13, a coolant storage tank 16 and a pipeline 17. The pipeline 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. The rated flow rate Q of the coolant is changed by adjusting the speed of the circulation pump 13 to adapt to the cooling requirements of the metal target 2 in different states. A liquid inlet 10 is arranged outside the liquid inlet channel 8, and a liquid outlet 11 is arranged outside the liquid outlet channel 9. One end of the pipeline 17 is connected to the liquid inlet 10, and the other end of the pipeline 17 is connected to the liquid outlet 11; a heat exchanger 14 is arranged on the pipeline 17, and the heat exchanger 14 is located between the liquid outlet 11 and the coolant storage tank 16. A heat exchange fan 15 is arranged on the pipe 17 between the heat exchangers 14. The structure disclosed in the invention works by air-cooling 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 liquid outlet 11 of the equipment is changed to ensure the normal operation of the equipment. Temperature sensors are arranged at the liquid inlet 10 and the liquid outlet 11 to monitor the coolant temperature at the liquid inlet 10 and the liquid outlet 11, so as to facilitate the control terminal to change the operation mode to adapt to the heat dissipation requirements of the X-ray tube in different states. The structure disclosed in the invention also includes a control terminal, which is electrically connected to the circulation pump 13, the heat exchange fan 15 and the temperature sensor to realize the intelligent operation of the cooling structure.

[0036] like Figure 6 The figure shows the flow process of the coolant in the manifold shunt channel of the structure disclosed in the present invention. The manifold shunt channel 7 and the sub-channels inside the heat dissipation microchannel 12 are in a vertical relationship. The manifold shunt channel 7 is connected to the liquid inlet channel 8 and the liquid outlet channel 9 respectively. The sub-channels in the manifold shunt channel 7 are divided into two categories, the liquid inlet sub-channels connected to the liquid inlet channel 8 and the liquid outlet sub-channels connected to the liquid outlet channel 9. The coolant enters the liquid inlet sub-channel of the manifold shunt channel 7 from the liquid inlet channel 8. Because the manifold shunt channel 7 and the sub-channels inside 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 liquid outlet sub-channel of the manifold shunt channel 7, and finally flows out from the liquid outlet channel 9.

[0037] In Example 2, the optimal dimensions of the heat dissipation microchannel 12 and the manifold diversion channel 7 are calculated by simulation analysis using finite element software, so that the temperature uniformity of the cooling structure is optimal and the energy efficiency ratio (COP) is maximized. The rated flow rate Q (g / s) of the coolant in the pipeline 17 is calculated as follows:

[0038] Q=C p (TT e )

[0039] Where: C Pis the specific heat of the coolant at normal pressure, T is the normal operating temperature of the metal target 2, T e is 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, the depth D of the heat dissipation microchannel 12 ranges from 1000Qμm to 2000Qμm, and the interval between adjacent channels is the same as the width W of the heat dissipation microchannel 12. This size has the greatest cooling capacity and is simple to process.

[0041] After calculation and analysis, the depth D of the manifold diversion channel 7 is m It mainly affects the uniformity of the coolant distribution in each channel of the heat dissipation microchannel 12 combined with it, and the depth D of the manifold diversion channel 7 m The larger the width W of the manifold shunt channel 7, the more uniform the distribution of the coolant flow in the multiple microchannels below it, and the better the temperature uniformity at the target surface of the metal target 2; m This mainly affects the cooling performance in the heat dissipation microchannel 12 below it. The width W of the manifold shunt channel 7 m The smaller the width W is, the longer the flow distance of the coolant in the heat dissipation microchannel 12 is, and the stronger the cooling ability of the coolant on the metal target 2 is. Therefore, the width W of the manifold diversion channel 7 is m The depth D of the manifold flow channel 7 is twice the width W of the heat dissipation microchannel 12. m The depth D of the heat dissipation microchannel 12 is four times, which can make the temperature uniformity of the cooling structure combining the manifold flow channel 7 and the heat dissipation microchannel 12 optimal and the energy efficiency ratio (COP) maximum.

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

[0043] S1. Install the cooling structure;

[0044] S2, the cooling structure starts to operate, and the temperature sensor set at the liquid outlet 11 detects the temperature T out , such as T out -T≤10℃, the equipment operates normally, such as T out -T>10℃, the control terminal controls the circulation pump 13 to increase the speed until T out -T≤10℃, if T out If the temperature cannot be lowered, the control terminal controls the heat exchange fan 15 to increase the speed;

[0045] S3, the temperature detected by the temperature sensor at the liquid inlet 10 is T in , such as T in <T e , the equipment is running normally, such as T in >T e, the control terminal controls the heat exchange fan 15 to speed up until T in <T e , if T in If the pressure cannot be reduced, the control terminal controls the circulating pump 13 to increase the speed;

[0046] S4. When the X-ray tube is running for a long time, the temperature detected by the temperature sensor at the liquid inlet 10 is T in Unable to drop to T e Next, the control terminal determines that the X-ray tube is overloaded and needs to be shut down for a rest. At this time, the cooling structure continues to work. in -T e When the temperature is higher than 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 lower boiling point and lower viscosity, reduces the flow resistance of the coolant in the heat dissipation microchannel 12, and can effectively change from liquid to steam, utilizing the latent heat of vaporization of the liquid to improve the cooling capacity of the cooling structure.

[0048] In the description of the present invention, the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "vertical", "horizontal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the purpose of describing the present invention rather than requiring the present invention to be constructed or operated in a specific position, and therefore should not be construed as limiting the present invention. The terms "connected" and "connected" in the present invention should be understood in a broad sense, for example, it can be a connection or a detachable connection; it can be a direct connection or an indirect connection through an intermediate component. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0049] The above is the preferred operation mode of the present invention, and the description of the specific operation mode is only used to better understand the concept of the present invention. For ordinary technicians in this technical field, several improvements or equivalent substitutions can be made according to the principles of the present invention, and these improvements or equivalent substitutions are also considered to fall within the protection scope of the present invention.

Claims

1. An X-ray tube anode direct cooling structure, comprising an anode component (1) and a cathode component (4), and an X-ray tube housing (6) wrapped externally, characterized in that: The anode component (1) comprises a copper column (3) and a metal target (2); a groove is arranged on the right side of the copper column (3); the metal target (2) is welded in the groove of the copper column (3); a filament (5) is arranged at the front end of the cathode component (4); the cathode component (4) is fixedly arranged on the right side of the X-ray tube housing (6); the front end of the copper column (3) and the metal target (2) are located inside the X-ray tube housing (6); the rear end of the copper column (3) is located outside the X-ray tube housing (6) and is fixed to the X-ray tube housing (6); a liquid inlet channel (8) and a liquid outlet channel (9) are arranged in the copper column (3); a manifold shunt channel (7) is arranged on the right side of the copper column (3); the manifold shunt channel (7) is connected to the liquid inlet channel (8) and the liquid outlet channel (9); a heat dissipation microchannel (12) is arranged on the left side of the metal target (2); the heat dissipation microchannel (12) is connected to the manifold shunt channel (7).

2. The X-ray tube anode direct cooling structure according to claim 1, characterized in that: A coolant circulation component is arranged outside the copper column (3), and the coolant circulation component comprises a circulation pump (13), a coolant storage tank (16) and a pipeline (17). The pipeline (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. A liquid inlet (10) is arranged outside the liquid inlet channel (8), and a liquid outlet (11) is arranged outside the liquid outlet channel (9). One end of the pipeline (17) is connected to the liquid inlet (10), and the other end of the pipeline (17) is connected to the liquid outlet (11).

3. The X-ray tube anode direct cooling structure according to claim 2, characterized in that: A heat exchanger (14) is arranged on the pipeline (17), and the heat exchanger (14) is located on the pipeline (17) between the liquid outlet (11) and the coolant storage tank (16). A heat exchange fan (15) is arranged outside the heat exchanger (14), and 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 the liquid outlet (11). The structure disclosed in the present invention further comprises a control terminal, which is electrically connected to the circulation pump (13), the heat exchange fan (15) and the temperature sensor.

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 pipeline (17) is calculated as follows: Q=C p (T-T e ) Where: C P is the specific heat of the coolant at normal pressure, T is the normal operating temperature of the metal target (2), T e is 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) has a value range of 200Qμm to 500Qμm, the depth D of the heat dissipation microchannel (12) has a value range of 1000Qμm to 2000Qμm, and the interval between adjacent channels is the same as the width W of the heat dissipation microchannel (12).

7. The X-ray tube anode direct cooling structure according to claim 6, characterized in that: The width W of the manifold diversion channel (7) is m The depth D of the manifold flow channel (7) is twice the width W of the heat dissipation microchannel (12). m 4 times the depth D of the heat dissipation microchannel (12).

8. A method for direct cooling of an X-ray tube anode, characterized in that: The following steps are involved: S1. Install the cooling structure; S2, the cooling structure starts to operate, and the temperature sensor set at the liquid outlet (11) detects the temperature T out , such as T out -T≤10℃, the equipment operates normally, such as T out -T>10℃, the control terminal controls the circulation pump (13) to increase the speed until T out -T≤10℃, if T out If the temperature cannot be lowered, the control terminal controls the heat exchange fan (15) to increase its speed; S3, the temperature detected by the temperature sensor at the liquid inlet (10) is T in , such as T in <T e , the equipment is running normally, such as T in >T e , the control terminal controls the heat exchange fan (15) to increase the 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 the speed; S4. When the X-ray tube is running for a long time, the temperature detected by the temperature sensor at the liquid inlet (10) is T in Unable to drop to T e Next, the control terminal determines that the X-ray tube is overloaded and needs to be shut down for a rest. At this time, the cooling structure continues to work. in -T e When the temperature is higher than 10℃, the control terminal determines that the X-ray tube can continue to work.

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