A water-cooling device for a 0.1T quasi-axisymmetric stellarator coil and its control method

Abstract

The present invention relates to the technical field of stellarator cooling, and provides a water cooling device and a control method for a 0.1T quasi-axisymmetric stellarator coil. Two horizontal pipes at different heights are respectively used to supply water to the modular coils of the stellarator, and are connected through a vertical pipe, which not only saves space but also improves the water supply efficiency. At the same time, a water tank integrated with a resistivity detector, a chiller, a circulation pump, sensors, deionization equipment and a deionized water preparation device together constitute a closed-loop cooling water circulation system, which can monitor the water quality in real time, precisely adjust the flow rate and pressure, continuously cool down and maintain a sufficient supply of deionized water, thereby ensuring the efficient cooling of the coils and the stable operation of the system.

Description

Technical Field

[0001] The present invention relates to the technical field of stellarator cooling, and more particularly, to a water cooling device for a 0.1T quasi-axisymmetric stellarator coil and a control method therefor. Background Art

[0002] The content of this part only provides background information related to the present invention, which may not constitute prior art.

[0003] The Chinese First Quasi-axisymmetric Stellarator (CFQS) is an important device in the exploration of controlled nuclear fusion, specifically designed to achieve stable, safe, and efficient operation of magnetic confinement fusion reactions. Its core lies in constructing a unique quasi-axisymmetric magnetic field configuration. The quasi-axisymmetric magnetic field configuration of this device combines the advantages of traditional stellarators and tokamaks, enabling both steady-state operation of the plasma and minimizing plasma transport losses, thereby improving its confinement quality. The experimental plan is divided into two key stages: the preliminary test stage and the experimental operation stage. In the preliminary test stage, the device will operate at a magnetic field strength of 0.1 tesla (0.1T), and its main purpose is to verify whether the quasi-axisymmetric magnetic field configuration and the neoclassical transport losses under this magnetic configuration are minimized, that is, to experimentally verify the scientific advancement of the quasi-axisymmetric magnetic field configuration. However, during the operation of the quasi-axisymmetric stellarator, a technical challenge cannot be ignored: a large amount of Joule heat is generated when the external magnetic field coils are energized, causing the coil temperature to rise rapidly, which may damage the coils.

[0004] Therefore, in order to ensure the smooth progress of the experiment and the long-term use of the device, an effective device and method for cooling the stellarator coils are urgently needed. Summary of the Invention

[0005] In order to solve the above technical problems, the purpose of the present invention is to provide a water cooling device for a 0.1T quasi-axisymmetric stellarator coil and a control method therefor. By optimizing the horizontal pipe structure, uniform delivery of cooling water is achieved, and at the same time, precise control of the valves and sensors on the horizontal pipes is carried out, thereby improving the cooling efficiency and ensuring the safe operation of the system.

[0006] Long-term stable operation of the stellarator coil is achieved.

[0007] The purpose of the present invention is achieved through the following technical solutions:

[0008] A water cooling device for a 0.1T quasi-axisymmetric stellarator coil, comprising:

[0009] Tokamak coil, the Tokamak coil includes a plurality of toroidally arranged three-dimensional non-planar modules, and each three-dimensional non-planar module includes a housing and a module coil wound by a conductor; the module coil is arranged in the housing, and a water-cooling channel for accommodating cooling water is defined in the conductor;

[0010] A plurality of horizontally connected pipes, the plurality of horizontal pipes are respectively arranged at different heights and surround the outside of the Tokamak coil; each horizontal pipe includes an inlet pipe and an outlet pipe, and the inlet pipes at different heights are connected to each other, and the outlet pipes at different heights are connected to each other; each inlet pipe is connected to the input end of the water-cooling channel through a plurality of branch pipes, and the output end of each water-cooling channel is connected to the outlet pipe; a plurality of first sensors are arranged on each branch pipe for detecting the temperature, pressure and flow rate of the branch pipe;

[0011] Water tank, a resistivity detector is arranged in the water tank for detecting the resistivity in the water tank;

[0012] Chiller, the chiller is connected to the water tank for continuously cooling the cooling water in the water tank;

[0013] Circulation pump, the input end of the circulation pump is connected to the water tank, and the output end of the circulation pump is connected to the input end of the horizontal pipe through a water supply pipe; the output end of the horizontal pipe is connected to the water tank through a return pipe; the circulation pump transports deionized water in the water tank into the horizontal pipe; a plurality of second sensors and instruments are arranged on the water supply pipe and the return pipe for detecting the temperature, pressure and flow rate of the water supply pipe and the return pipe;

[0014] Deionization equipment, the deionization equipment is connected to the water tank for adsorbing ions in the cooling water in the water tank and increasing the resistivity of the cooling water;

[0015] Deionized water preparation device, the input end of the deionized water preparation device is connected to an external water source, and the output end of the deionized water preparation device is connected to the water tank; used to supplement deionized water to the water tank.

[0016] Further, the horizontal pipe is in a C shape.

[0017] Further, a filtering device is further included, and the filtering device is connected to the water tank; a resistivity detector is arranged on the water tank, and when the detected value of the resistivity detector is lower than a preset threshold, the filtering device is turned on and continuously purifies the cooling water in the water tank.

[0018] Further, an exhaust valve is arranged on the horizontal pipe for exhausting the gas in the pipe.

[0019] Further, a bypass valve is further arranged on the horizontal pipe for assisting in adjusting the flow rate in the horizontal pipe.

[0020] Further, a liquid level sensor is further arranged in the water tank for detecting the liquid level in the water tank.

[0021] Furthermore, it further includes a control cabinet, and the multiple sensors include a pressure sensor, a temperature sensor, and a flow sensor; the control cabinet is electrically connected to the liquid level sensor, the circulation pump, the deionized water preparation device, the resistivity detector, the pressure sensor, the flow sensor, and the temperature sensor respectively;

[0022] When the circulation pump is in the stopped state, the control cabinet controls the deionized water preparation device to inject cooling water into the water tank until the cooling water reaches the preset water level;

[0023] When the circulation pump is in the started state, the control cabinet monitors the pressure value, temperature value, and flow value of the pipeline through the pressure sensor, the flow sensor, and the temperature sensor; when the pressure value, temperature value, and flow value are lower than the corresponding preset thresholds, the control cabinet alarms through the alarm device. Furthermore, it further includes:

[0024] On the branch circuit, a first ball valve, a flow regulating valve, and a pressure sensor are provided at the inlet of the water cooling channel, and a temperature sensor, a flow sensor, and a second ball valve are provided at the outlet of the water cooling channel; the first ball valve and the second ball valve are used to quickly switch a single branch circuit; the regulating valve is used to regulate the pressure and flow in the water cooling channel; the pressure sensor is used to detect the pressure value at the inlet, and the temperature sensor and the flow sensor are used to detect the temperature and flow data at the outlet.

[0025] In some possible embodiments, the present invention further provides a control method for a water cooling device, which is applied to the above water cooling device, and the method includes the following steps:

[0026] S1. Start the deionized water preparation device to convert the external water source into deionized water and transport it to the water tank;

[0027] S2. Continuously detect the cooling water in the water tank by using the resistivity detector. If the detected value of the resistivity detector is lower than the preset threshold, start the filtering device to continuously purify the cooling water in the water tank until the detected value of the resistivity detector reaches the preset threshold;

[0028] S3. Start the chiller to continuously cool down the cooling water in the water tank;

[0029] S4. Start the circulation pump to transport the deionized water in the water tank to the horizontal pipeline; adjust the flow and pressure of the water supply pipe to the preset target by controlling the rotation speed of the circulation pump and the first valve on the water supply pipe;

[0030] S5. Obtain the pressure and flow data of each branch circuit according to the pressure and flow sensors on each branch circuit, and control the inlet pressure and flow of the water cooling channel through the regulating valve on each branch circuit so that the flow and pressure of each water cooling channel reach the preset requirements;

[0031] S6. After the cooling water in the branch returns to the water tank, repeat steps S1 to S5.

[0032] Furthermore, the above method further includes:

[0033] Calculate and output the average temperature rise of the cooling water according to the calculation model. The calculation model includes: calculating the flow velocity of the cooling water according to the preset pressure value, the parameters of the water-cooled channel, and the flow rate of the cooling water; based on the stellarator operating at a preset magnetic field strength, calculating the average temperature rise according to the corresponding heat release power, water-cooling power, and the parameters of the stellarator coil.

[0034] In summary, the technical solutions of the embodiments of the present invention have at least the following advantages and beneficial effects:

[0035] The present invention cools the coil with deionized water to prevent the coil from being damaged by high temperature.

[0036] By adopting the design of multi-layer interconnected horizontal pipes, the present invention effectively disperses the water supply path, optimizes the space layout, and is convenient for observation and maintenance. Specifically, two C-shaped horizontal pipes are used to supply water to the modular coils of the stellarator respectively, and are connected through vertical pipes, which not only saves space but also improves the water supply efficiency. At the same time, the water tank integrated with the resistivity detector, the chiller, the circulation pump, the sensor, and the deionization equipment and the deionized water preparation device together constitute a closed-loop cooling water circulation system, which can monitor the water quality in real time, precisely adjust the flow rate and pressure, continuously cool down and maintain the sufficient supply of deionized water, thereby ensuring the efficient cooling of the coil and the stable operation of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic structural diagram of a water-cooling device for a 0.1T quasi-axisymmetric stellarator coil provided by the present invention;

[0038] Figure 2 It is a schematic structural diagram of the water tank, chiller, deionization equipment, deionized water preparation device, and multiple sensors and valves in the present invention;

[0039] Figure 3 It is a schematic structural diagram of the branch in the present invention;

[0040] Figure 4 It is a flowchart of the water-cooling device control method in the present invention.

[0041] Icons: 1. Stellarator coil; 11. Module coil; 2. Horizontal pipeline; 21. Exhaust valve; 22. Bypass valve; 23. Branch; 231. First ball valve; 232. Flow regulating valve; 236. Second ball valve; 3. Circulation pump; 4. Chiller; 5. Water tank; 51. Resistivity detector; 52. Liquid level sensor; 6. Deionized water preparation device; 7. Deionization equipment; 8. Water supply pipe; 9. Water return pipe. Detailed implementation mode

[0042] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention usually described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0043] The following refers to Figures 1 to 4 to further elaborate on the present invention.

[0044] As Figure 1 and Figure 4 shown, a water cooling device for a 0.1T quasi-axisymmetric stellarator coil 1 proposed in an embodiment of the present invention includes:

[0045] The stellarator coil 1, the stellarator coil includes a plurality of three-dimensional non-planar modules, and each three-dimensional non-planar module includes a housing and a module coil 11 wound by a conductor; the module coil 11 is arranged in the housing, and a water cooling channel for accommodating cooling water is defined in the conductor;

[0046] Among them, the module coil 11 is the source of generating the magnetic field, and an electric current is passed through it to form the required magnetic field environment. The water cooling channel is arranged in the module coil 11 and is responsible for effectively transporting the heat generated by the coil during operation to the cooling water in the water cooling channel. Through the flow of the cooling water, the heat generated by the coil is conducted out. To ensure the high efficiency and safety of heat exchange, deionized water is used as the cooling water. By utilizing the non-conductive effect of deionized water, both the problem of current short circuit is avoided and the effective transfer of heat is ensured. This design enables the stellarator coil 1 to maintain stable performance and temperature under long-term and high-intensity working conditions, thereby extending the service life and reliability of the equipment.

[0047] Multiple interconnected horizontal pipes 2 are provided at different heights and surround the outside of the stellarator coil 1. Each horizontal pipe 2 includes an inlet pipe and an outlet pipe. The inlet pipes at different heights are interconnected, and the outlet pipes at different heights are interconnected. Each inlet pipe is connected to the input end of the water-cooling channel through multiple branch pipes 23, and the output end of each water-cooling channel is connected to the outlet pipe. Multiple first sensors are provided on each branch pipe 23 to detect the temperature, pressure, and flow rate of the branch pipe 23.

[0048] Specifically, as Figure 1 shown, multiple interconnected horizontal pipes 2 are used. These pipes are arranged at different heights and surround the outside of the modular coils 11 of the stellarator. Since the number of modular coils 11 is 16, if only a single horizontal pipe 2 is used to supply water to each modular coil 11 in sequence, the modular coils 11 located at the end of the sequence will not be effectively cooled. At the same time, if each modular coil 11 is connected to a water source for water supply, the water supply equipment will be complex and crowded. Therefore, a two-layer platform, that is, two C-shaped horizontal pipes 2, is set up to supply water to the stellarator coil 1 respectively. Each layer of C-shaped horizontal pipe 2 corresponds to 8 modular coils 11, and the two C-shaped horizontal pipes 2 are interconnected through a vertical pipe, thus realizing the water supply to the two C-shaped horizontal pipes 2, saving space and improving efficiency.

[0049] The water tank 5, as one of the key components of the water-cooling system, is equipped with a resistivity detector 51 inside to monitor the resistivity situation in the water tank 5 in real time. Once the resistivity does not meet the requirements, the system will start the water quality treatment process to ensure that the resistivity of the deionized water reaches the standard of 5 MΩ·cm. At the same time, the chiller 4 is connected to the water tank 5 to continuously cool the cooling water in the water tank 5 to ensure that the cooling water can always be maintained within a lower temperature range, thereby improving the cooling effect of the coil. In addition, a liquid level sensor 52 is provided in the water tank 5 to detect the liquid level in the water tank 5.

[0050] The circulation pump 3 is responsible for transporting the deionized water in the water tank 5 into the horizontal pipe 2. At the same time, the circulation pump 3 can adjust the rotation speed and cooperate with the valve to adjust the flow rate and pressure, and through the cooperation with the valve, the flow rate and pressure can be accurately adjusted to meet different requirements during the coil cooling process. The input end of the circulation pump 3 is connected to the water tank 5, and the output end of the circulation pump 3 is connected to the input end of the horizontal pipe 2 through the water supply pipe 8. The output end of the horizontal pipe 2 is connected to the water tank 5 through the return pipe 9. On the water supply pipe 8 and the return pipe 9, multiple second sensors and instruments are also provided, such as Figure 2As shown, the pressure sensor 81 and the temperature sensor 82 are used to detect the temperature and pressure of the water supply pipe 8, and the pressure sensor 91, the temperature sensor 92 and the flow sensor 93 are used to detect the pressure, temperature and flow rate of the return water pipe 9. These sensors can real-time feedback the operating state of the system. Once an abnormal situation is detected, the system will immediately give an alarm and take corresponding emergency treatment measures.

[0051] The deionization device 7 and the deionized water preparation device 6 are arranged to maintain an adequate supply of deionized water in the water tank 5. The deionization device 7 is connected to the water tank 5 and is used to adsorb the ions in the cooling water in the water tank 5 to increase the resistivity of the cooling water; the input end of the deionized water preparation device 6 is connected to an external water source, and the output end of the deionized water preparation device 6 is connected to the water tank 5 and is used to supplement deionized water to the water tank 5.

[0052] Furthermore, a filtering device is also included. The filtering device can adopt a resin tank or / and a filter, and the filtering device is connected to the water tank 5; a resistivity detector 51 is provided on the water tank 5. When the detected value of the resistivity detector 51 is lower than a preset threshold, it means that the water quality has deteriorated to the extent that it is no longer suitable for directly cooling the coil and may contain more impurities or ions. Therefore, the filtering device is controlled to be turned on, and the cooling water in the water tank 5 is continuously purified to remove the impurities and bad ions therein, thereby improving the purity and resistivity of the water quality. Through this process, the filtering device ensures that the cooling water in the water tank 5 always maintains a high-quality standard suitable for coil cooling, effectively avoiding the decline in coil performance or failure caused by water quality problems, and further improving the reliability of the water cooling system and the service life of the coil.

[0053] Furthermore, an exhaust valve 21 is provided on the horizontal pipe 2 and is used to exhaust the gas in the horizontal pipe 2. A bypass valve 22 is also provided on the horizontal pipe 2 and is used to assist in regulating the flow rate in the horizontal pipe 2.

[0054] Among them, the exhaust valve 21 is arranged on the highest horizontal pipe 2 and is designed to exhaust the gas in the pipe. During the start-up or operation of the pipe system, due to various reasons (such as medium temperature change, flow rate change, etc.), gas may accumulate inside the pipe, resulting in abnormal pressure increase. At this time, the exhaust valve 21 can play its role and discharge the gas in the pipe through automatic or manual means, thereby maintaining the stability of the pressure inside the pipe. Prevent the pipe from bursting due to overpressure, protect the equipment in the pipe system and ensure the normal operation of the system.

[0055] The setting of the bypass valve 22 is designed to assist in regulating the flow rate in the horizontal pipe 2. In the pipe system, the flow rate is one of the key factors determining the system performance. By adjusting the bypass valve 22, the flow rate through the main pipe can be flexibly controlled, thereby achieving precise regulation of the overall flow rate of the system.

[0056] Furthermore, it also includes a control cabinet, which is designed to monitor and operate the entire water cooling system. Meanwhile, there are multiple sensors including pressure sensors, temperature sensors and flow sensors; the control cabinet is electrically connected to the liquid level sensor 52, the circulation pump 3, the deionized water preparation device 6, the resistivity detector 51, the pressure sensors, the flow sensors and the temperature sensors respectively, so as to obtain the operating status of each position.

[0057] Specifically, the control cabinet is connected to the liquid level sensor 52, and can monitor the water level in the water tank 5 in real time. When the circulation pump 3 (responsible for pushing the cooling water to circulate in the system) is in a stopped state, if the water level is lower than the preset water level, the control cabinet will automatically control the deionized water preparation device 6 to inject cooling water into the water tank 5 until the water level reaches the preset water level, ensuring that there is enough cooling water in the system to maintain the cooling of the coil.

[0058] When the circulation pump 3 is in a started state, the control cabinet monitors the pressure value, temperature value and flow value in the pipeline through its connections with the pressure sensors, flow sensors and temperature sensors. These sensors are respectively installed on the water supply pipe 8, the water return pipe 9 and the branch 23 to ensure that the operating status of the system can be comprehensively monitored. If the monitored pressure value, temperature value and flow value are lower than the safety thresholds preset by the control cabinet, the control cabinet will send an alarm signal through the alarm device, prompting the operator to conduct an inspection or take corresponding measures to ensure the safe operation of the system and the effective cooling of the coil, thus guaranteeing the stable operation of the nuclear fusion experimental device.

[0059] Furthermore, as Figure 3 shown, it also includes: on the branch 23, at the inlet of the water cooling channel, there are a first ball valve 231, a flow regulating valve 232 and a pressure sensor 233; at the outlet of the water cooling channel, there are a temperature sensor 234, a flow sensor 235 and a second ball valve 236. In order to precisely control and monitor the flow of the cooling water, in this embodiment, precise adjustment is carried out for each module coil 11. Specifically, at the water inlet of each coil, that is, the inlet of the branch 23, the system installs a first ball valve 231, a flow regulating valve 232 and a pressure sensor 233. The main functions of the first ball valve 231 and the flow regulating valve 232 are to regulate the flow rate of the cooling water entering the coil to ensure that the coil is properly cooled. By adjusting these valves, the flow rate of the water flow can be controlled, thereby affecting the cooling effect of the coil. And the pressure sensor 233 is used to monitor the pressure value at the inlet of the water cooling channel, which is a key parameter because the flow rate and pressure of water are directly related, and the magnitude of the pressure is also related to the safe operation of the system. If the pressure is too high, it may cause damage to the coil or pipeline; if the pressure is too low, the cooling effect may be poor.

[0060] At the outlet of the water-cooling channel, i.e., the water outlet end of branch 23, a temperature sensor 234, a flow sensor 235, and a second ball valve 236 are arranged. The temperature sensor 234 is responsible for monitoring the temperature of the water outlet, which is a direct indicator for evaluating the cooling effect of the coil. The flow sensor 235 is used to measure the actual water flow rate to ensure that the flow rate meets the design requirements. The function of the second ball valve 236 here is also to regulate the flow rate and work in coordination with the first ball valve 231 at the inlet to ensure the flow balance and control of the entire cooling system.

[0061] Based on the same inventive concept, as Figure 4 shown, an embodiment of the present invention provides a control method for a water-cooling device, which is applied to the above-mentioned water-cooling device. The method includes the following steps:

[0062] S1, Start the deionized water preparation device 6 to convert external water sources (such as tap water) into deionized water and transmit it to the water tank 5.

[0063] S2, Continuously detect the cooling water in the water tank 5 by using the resistivity detector 51. If the detected value of the resistivity detector 51 is lower than 5 MΩ·cm, start the filtration device to continuously purify the cooling water in the water tank 5 until the detected value of the resistivity detector 51 reaches the preset threshold. Specifically, at the startup stage, the resistivity detector 51 first detects the water quality. When it is found that the water quality in the water tank 5 cannot meet the cooling requirements of the module coil 11, the filtration device (i.e., the resin tank and the filter) is used to increase the resistivity of the cooling water, so as to avoid excessive impurities in the cooling water from entering the module coil 11 and ensure the cooling effect of the module coil 11.

[0064] S3, Start the chiller 4 to continuously cool down the cooling water in the water tank 5. Specifically, the cooling water of the entire water-cooling device needs to be recycled. Therefore, after the cooling water returns from the module coil 11 to the water tank 5, it will increase the temperature of the water tank 5. Therefore, the present invention uses the chiller 4 to cool down the cooling water in the water tank 5, so as to ensure that the cooling water entering the module coil 11 is at a relatively low level, and thus ensure the cooling effect.

[0065] S4, Start the circulation pump 3 to transport the deionized water in the water tank 5 to the horizontal pipe 2; by controlling the rotation speed of the circulation pump 3 and the first valve on the water supply pipe 8, adjust the flow rate and pressure of the water supply pipe 8 (or the cooling water entering the module coil 11) to the preset target.

[0066] S5. Obtain the pressure data of each branch 23 based on the pressure sensors on each branch 23, and control the inlet water pressure of the water-cooling channels through the ball valves and flow regulating valves 232 on each branch 23, so that the flow rate and pressure of each water-cooling channel meet the preset requirements. Specifically, after injecting cooling water into the water supply pipe 8, it is also necessary to adjust the cooling water of each branch 23 again to meet the requirements of each module coil 11. That is, the cooling water of the coil needs to reach a certain flow rate, but the higher the flow rate, the greater the pressure loss will be. To ensure the safe operation of the system, the pressure limit of the system cannot be exceeded. Determine parameters such as the flow rate and pressure of each branch 23 through theoretical calculations and experimental tests, and then control them through the ball valves and flow regulating valves 232 according to the flow rate and pressure data.

[0067] S6. When the cooling water in the branch 23 returns to the water tank 5, repeat steps S1 to S5. That is, when the cooling water in the branch 23 carries heat back to the water tank 5, repeat the steps of removing impurities and cooling again, so that the cooling water can be recycled.

[0068] It should be noted that for the data detection and control of each sensor, the control cabinet can be directly connected to the sensor, or the central control system can be used to remotely control the control cabinet, enabling the staff to remotely obtain the detection information and alarm information, ensuring the safe operation of the stellarator.

[0069] Furthermore, the method further includes:

[0070] Calculate and output the average temperature rise of the cooling water according to the calculation model. The calculation model includes: calculate the flow velocity of the cooling water according to the preset pressure value, the parameters of the water-cooling channel, and the flow rate of the cooling water; based on the stellarator operating at a preset magnetic field strength, calculate the average temperature rise according to the corresponding heat release power, water-cooling power, and the parameters of the module coil.

[0071] Specifically, under the 0.1T steady-state discharge condition, select different water-cooling pressure drops to calculate the average temperature rise and flow velocity of the cooling water. The specific process is as follows:

[0072] Fix the water-cooling pressure drop and calculate the flow velocity of the cooling water. The pressure change at the cooling inlet and outlet is calculated by the Hazen-Williams formula:

[0073]

[0074] where h f is the head loss, in m; L is the length of a cooling pipe, in m; Q is the flow rate in the pipe, in m 3 / s; C is the roughness coefficient (i.e., the Hazen-Williams coefficient = 100 200), D is the inner diameter of the pipe, in m; the acceleration due to gravity g = 9.8 m / s 2 , the density of water , is the pressure drop, in Pa, A is the cross-sectional area of the cooling holes, in m 2 ; u is the flow velocity, in m / s.

[0075] Calculate the average temperature rise of the cooling water. For the continuous operation of 0.1 T, it is obtained from the heat equation:

[0076]

[0077] Among them, the heat capacity of the copper wire , the specific heat capacity of the copper wire is C p , in J / K; P h is the heat release power, in W; is the water cooling power, in W; j is the current density, in A / mm 2 ; is the resistivity, in . L is the length of the copper wire, in m; is the cross-sectional area of the copper wire, in m 2 .

[0078] Thus, the temperature change of the conductor is obtained:

[0079]

[0080] So the heat generation power of the coil is calculated as follows:

[0081]

[0082] Considering water cooling (neglecting air heat conduction), calculate the average temperature rise of the cooling water according to the energy conservation formula:

[0083]

[0084] Among them, u is the water flow velocity, in m / s; is the density of water, in kg / m 3 ; is the density of the copper wire, in kg / m 3 ; r is the radius of the pipe, in m; is the specific heat capacity of water, in J / (kg K); is the average temperature difference between the inlet and outlet water flows, that is, the average temperature rise, in K.

[0085] Based on the above formulas, the pressure drops are fixed at 1.5 MPa, 2 MPa, and 2.5 MPa respectively, and the average temperature rise of the cooling water under different water-cooling pressure drops is calculated. The specific parameters of the Module Coil (MC) are shown in Tables 1 to 3:

[0086] Table 1 Cooling parameters of the MC coil when the water-cooling pressure drop is 1.5 MPa

[0087]

[0088] Table 2 Cooling parameters of the MC coil when the water-cooling pressure drop is 2 MPa

[0089]

[0090] Table 3 Cooling parameters of the MC coil when the water-cooling pressure drop is 2.5 MPa

[0091]

[0092] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A water cooling device for a 0.1T quasi-axisymmetric stellarator coil, characterized in that, Comprising: A stellarator coil, the stellarator coil including a plurality of toroidally arranged three-dimensional non-planar modules, each three-dimensional non-planar module including a housing and a module coil wound by a conductor; the module coil is arranged inside the housing, and a water-cooling channel for accommodating cooling water is defined inside the conductor; A plurality of horizontally connected pipes, the plurality of horizontally connected pipes being respectively arranged at different heights and surrounding the outside of the stellarator coil; each of the horizontally connected pipes includes an inlet pipe and an outlet pipe, and the inlet pipes at different heights are connected to each other, and the outlet pipes at different heights are connected to each other; one end of each inlet pipe is connected to the input end of the water-cooling channel through a plurality of branch paths, and the output end of each water-cooling channel is connected to the outlet pipe through the other end of the branch path; a plurality of sensors are arranged on each branch path for detecting the temperature, pressure and flow rate of the branch path; A water tank, in which a resistivity detector is arranged for detecting the resistivity in the water tank; A chiller, which is connected to the water tank for continuously cooling the cooling water in the water tank; A circulation pump, the input end of the circulation pump is connected to the water tank, and the output end of the circulation pump is connected to the input end of the horizontally connected pipe through a water supply pipe; the output end of the horizontally connected pipe is connected to the water tank through a return pipe; the circulation pump conveys deionized water in the water tank into the horizontally connected pipe; a plurality of sensors and instruments are arranged on both the water supply pipe and the return pipe for detecting the temperature, pressure and flow rate of the water supply pipe and the return pipe; A deionization device, which is connected to the water tank for adsorbing ions in the cooling water in the water tank to increase the resistivity of the cooling water; A deionized water preparation device, the input end of the deionized water preparation device is connected to an external water source, and the output end of the deionized water preparation device is connected to the water tank; for supplementing deionized water to the water tank.

2. The water cooling device according to claim 1, characterized in that: The horizontally connected pipe is in a C shape.

3. The water cooling device according to claim 1, wherein: It further includes a filtering device, the filtering device is connected to the water tank; a resistivity detector is arranged on the water tank, and when the detected value of the resistivity detector is lower than a preset threshold, the filtering device is turned on and continuously purifies the cooling water in the water tank.

4. The water cooling device according to claim 1, wherein: An exhaust valve is arranged on the horizontally connected pipe for exhausting the gas in the pipe.

5. The water cooling device according to claim 4, characterized in that: A bypass valve is further arranged on the horizontally connected pipe for assisting in adjusting the flow rate in the horizontally connected pipe.

6. The water cooling device according to claim 1, wherein: A liquid level sensor is further arranged in the water tank for detecting the liquid level in the water tank.

7. The water cooling device according to claim 6, wherein: It further includes a control cabinet, and the plurality of sensors include a pressure sensor, a temperature sensor and a flow sensor; the control cabinet is electrically connected to the liquid level sensor, the circulation pump, the deionized water preparation device, the resistivity detector, the pressure sensor, the flow sensor and the temperature sensor respectively; When the circulation pump is in a stopped state, the control cabinet controls the deionized water preparation device to inject cooling water into the water tank until the cooling water reaches a preset water level; When the circulation pump is in the starting state, the control cabinet monitors the pressure value, temperature value and flow value of the pipeline through the pressure sensor, the flow sensor and the temperature sensor; when the pressure value, temperature value and flow value are lower than the corresponding preset thresholds, the control cabinet alarms through the alarm device.

8. The water cooling device according to claim 1, characterized in that It further includes: On the branch, a first ball valve, a regulating valve and a pressure sensor are provided at the inlet of the water-cooling channel, and a temperature sensor, a flow sensor and a second ball valve are provided at the outlet of the water-cooling channel; the first ball valve and the second ball valve are used to quickly switch a single branch: the regulating valve is used to adjust the pressure and flow in the water-cooling channel; the pressure sensor is used to detect the pressure value at the inlet, and the temperature sensor and the flow sensor are used to detect the temperature and flow data at the outlet.

9. A control method for a water cooling device, characterized in that, Applied to the water-cooling device according to any one of claims 1 to 8, the method includes the following steps: S1, Start the deionized water preparation device to convert the external water source into deionized water and transport it to the water tank; S2, Continuously detect the cooling water in the water tank by using a resistivity detector. If the detected value of the resistivity detector is lower than the preset threshold, start the filtering device to continuously purify the cooling water in the water tank until the detected value of the resistivity detector reaches the preset threshold; S3, Start the chiller to continuously cool down the cooling water in the water tank; S4, Start the circulation pump to transport the deionized water in the water tank into the horizontal pipeline; by controlling the rotation speed of the circulation pump and the first valve on the water supply pipe, adjust the flow and pressure of the water supply pipe to the preset target; S5, Obtain the pressure and flow data of each branch through the pressure and flow sensors on each branch, and control the pressure and flow of the water-cooling channel through the flow regulating valves on each branch, so that the flow and pressure of each water-cooling channel reach the preset requirements; S6, When the cooling water in the branch returns to the water tank, repeat steps S1 to S5.

10. The control method according to claim 9, characterized in that, The method further includes: Calculate and output the average temperature rise of the cooling water according to the calculation model. The calculation model includes: calculate the flow velocity of the cooling water according to the preset pressure value, the parameters of the water-cooling channel and the flow rate of the cooling water; based on the stellarator operating at a preset magnetic field strength, calculate the average temperature rise according to the corresponding heat release power, water-cooling power and the parameters of the stellarator coil.

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