Radiometer probe for a future fusion reactor

Abstract

The application discloses a radiation calorimeter probe of a future fusion reactor and relates to the technical field of magnetic confinement nuclear fusion device diagnosis technology. The probe comprises an external protective sleeve, a chip structure arranged in the internal of the external protective sleeve, an internal fixing structure for fixing the chip structure and a cooling pipeline. The external protective sleeve is made of non-magnetic stainless steel, and the cooling pipeline is arranged in the wall of the external protective sleeve or in the internal space. The chip structure comprises an absorbing film, an insulating layer and a measuring circuit comprising a thermistor which are arranged in sequence. The application realizes stable measurement of radiation power under the extreme environment of the fusion reactor through material optimization and structure integration, improves the reliability and maintenance convenience of the probe and meets the long pulse operation requirement of the future fusion reactor.

Description

Technical Field

[0001] This invention relates to the field of diagnostic technology for magnetic confinement nuclear fusion devices, and specifically to a radiation calorimeter probe for a future fusion reactor. Background Technology

[0002] Nuclear fusion energy has five major advantages: safety, abundant fuel, high energy efficiency, long lifespan, minimal radioactive waste, and no greenhouse gas emissions. In magnetic confinement fusion devices, the radiation calorimeter system is a crucial diagnostic tool used to measure the total plasma radiation power loss, providing vital data support for energy balance studies. Through inversion of diagnostic data, the spatiotemporal evolution of plasma radiation power density can be calculated, providing important plasma parameter information for cutting-edge physics research such as impurity transport, plasma fragmentation, and radiation divertors.

[0003] The main challenges for diagnostics in future fusion reactors include: first, extremely high radiation and neutron flux; second, the requirement for extremely high stability and reliability during ultra-long pulse operation; and third, the necessity of remote maintenance. In future fusion reactors, high temperatures and large amounts of bremsstrahlung (bremsstrahlung radiation) are the main channels for energy loss and play a crucial role in energy confinement. When calculating the fusion triple product of ignition conditions in the Lawson criterion, the energy confinement time needs to be subtracted from the bremsstrahlung radiation. Bremsstrahlung is a continuous spectrum with an energy range of 0.1 keV to 200 keV, mainly consisting of soft X-rays, with typical peak values ​​of 1–10 keV. It primarily originates from Coulomb collisions between electrons and ions in the plasma and is the main soft X-ray source in tokamas. The importance of radiation calorimeters for future fusion reactors lies primarily in measuring bremsstrahlung. Radiation power loss accounts for approximately 30-50% of the heating power, which is crucial for plasma energy confinement. Furthermore, radiation calorimeters can also provide diagnostic measurements and feedback for future fusion impurity control, divertor radiation (such as X-ray point radiation), and off-target effects. Therefore, the design and development of radiation calorimeters for future fusion reactors is of great importance.

[0004] However, China's technological reserves in the field of fusion diagnostics are still weak, and radiation calorimeter systems have long relied on imports, highlighting the urgent need for breakthroughs in independent research and development capabilities. In existing experimental devices, due to the relatively low plasma temperature, bremsstrahlung accounts for a limited share of the total radiation, and its influence can often be ignored when calculating energy confinement time, which to some extent masks the shortcomings of existing diagnostic systems. However, the high-temperature and high-density environment of future fusion reactors will lead to a significant increase in the proportion of strong bremsstrahlung, and the increased radiation loss will directly lead to a deterioration of plasma energy confinement, and even discharge failure. Under these circumstances, the urgency of developing radiation calorimeters as core measurement and diagnostic tools is becoming increasingly apparent. Even more challenging is that existing radiation calorimeter systems did not fully consider the extreme operating conditions of future reactors in their initial design, and generally suffer from serious design flaws: most probes use gold thin films as the absorbing material. Although gold performs excellently at room temperature, under the high-energy neutron irradiation of 14 MeV in future reactors, gold nuclei will transpose into mercury (Hg) through the (n,γ) reaction. This transmutation not only alters the physicochemical properties of materials, leading to decreased thermal conductivity and changes in melting point, thus causing measurement inaccuracies, but more seriously, mercury's high volatility makes it highly susceptible to contaminating expensive vacuum chambers, causing irreversible equipment damage. Furthermore, existing systems are unable to effectively address material swelling caused by extremely high neutron irradiation, thermal stress fatigue due to high heat loads, and signal noise problems caused by strong electromagnetic interference.

[0005] Therefore, in order to meet the needs of future fusion reactors, developing a new type of radiation calorimeter that is resistant to neutron irradiation, high heat load, strong electromagnetic shielding, and remote maintenance capabilities is not only a technological upgrade, but also related to the engineering design and safe operation of fusion reactors. Summary of the Invention

[0006] This invention provides a radiation calorimeter probe for future fusion reactors, which solves the technical problems of measurement inaccuracy and maintenance difficulties caused by existing probes due to the inability of materials to withstand neutron irradiation, low signal-to-noise ratio under high temperature conditions, and lack of electromagnetic shielding.

[0007] This invention is achieved through the following technical solution:

[0008] This application provides a radiation calorimeter probe for a future fusion reactor, comprising:

[0009] An outer protective sleeve, a chip structure disposed inside the outer protective sleeve, an internal fixing structure for fixing the chip structure, and cooling pipes;

[0010] The outer protective sleeve is made of non-magnetic stainless steel, and the cooling pipe is built into the wall or internal space of the outer protective sleeve.

[0011] The chip structure includes an absorption film, an insulating layer, and a measurement circuit containing a thermistor, which are stacked sequentially.

[0012] A further optimization is that the cooling pipe extends along the axial direction of the outer protective sleeve, or is spirally coiled around the periphery of the chip structure;

[0013] Coolant flows through the cooling pipe, and the coolant is selected from one or more combinations of light water, heavy water, or liquid nitrogen.

[0014] A further optimized solution is that the absorbing film, thermistor, and measurement circuit are made of neutron-resistant materials;

[0015] The neutron-resistant material is selected from pure tungsten, platinum, or an alloy of rhenium-tungsten, molybdenum-rhenium, platinum-rhodium.

[0016] A further optimization is to set the thickness of the absorbing film to 0.1 μm to 100 μm, so as to maintain structural stability and not generate mercury transmutation products under 14 MeV neutron irradiation.

[0017] A further optimized solution is that the insulating layer is made of a material that simultaneously meets the requirements of high temperature resistance, 14 MeV neutron irradiation resistance, insulation stability, low activation and vacuum compatibility.

[0018] The material is selected from one of diamond, silicon carbide, or silicon nitride.

[0019] A further optimization is that the insulating layer is made of silicon nitride material, which is used to maintain an insulation resistance greater than 10¹² Ω·cm under operating conditions of annual dose ≤25 dpa and temperature 500 ℃ to 800 ℃.

[0020] A further optimization is that the outer protective sleeve is a one-piece molded structure, which is configured to also have electromagnetic shielding function to shield the strong magnetic field interference inside the fusion reactor.

[0021] A further optimized solution is that the probe is configured as an integral pluggable module, and the external protective cover is fixed to the first wall of the fusion reactor through a detachable connection to support complete replacement during remote operation.

[0022] A further optimized solution is that the detachable connection method is a screw fastening connection;

[0023] The outer protective sleeve is also provided with an observation window, which is a wedge-shaped notch used to limit the incident angle of plasma thermal radiation.

[0024] A further optimized solution is that the probe also includes a signal lead-out wire and an aviation connector;

[0025] One end of the signal lead is connected to the chip structure, and the other end passes through the internal fixing structure and is led out through the external protective sleeve and connected to the aviation plug.

[0026] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0027] This invention solves the problem of the impact of neutron irradiation on the internal chip of the probe. The absorption thin film material, the thermistor, and circuit materials can be pure metals such as tungsten or platinum, or alloys such as rhenium-tungsten alloy, molybdenum-rhenium alloy, or platinum-rhodium alloy. The insulating material on the chip (e.g., diamond) must simultaneously meet five core requirements: high temperature resistance (≥500℃, extreme ≥1000℃), resistance to 14 MeV neutron irradiation, stable insulation, low activation, vacuum compatibility, and low gas escape rate. These materials can effectively solve the activation and radiation problems under neutron radiation conditions.

[0028] This effectively solves the problems of heat load and cooling. The ambient temperature near the first wall in a fusion reactor is high, but the signal-to-noise ratio of the chip sensor can be low at high temperatures. Therefore, the heat load problem needs to be considered. A protective jacket made of non-magnetic stainless steel (such as 304 and 316 stainless steel) is used to protect the internal components of the probe from the high-temperature environment near the first wall, reducing the impact of high temperatures on the probe's internal components and measurements. The stainless steel jacket has cooling channels in the middle, allowing for the addition of coolant. The coolant can be light water, heavy water, or liquid nitrogen, etc.

[0029] The stainless steel protective sleeve effectively solves problems such as electromagnetic shielding and can be used as an electromagnetic shielding structure to reduce the impact of strong magnetic fields in the fusion reactor on the internal circuitry of the chip.

[0030] This effectively solves the problem of remote maintenance. By modularizing the core, supporting components, and stainless steel protective sleeve, only the entire module needs to be removed and replaced with a new one when remote maintenance is required. This facilitates remote operation. Attached Figure Description

[0031] To more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be considered as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort. In the drawings:

[0032] Figure 1 This is a schematic diagram of the design of a radiation calorimeter probe provided in an embodiment of this application;

[0033] Figure 2 This is a schematic diagram of the chip structure of the radiation calorimeter provided in an embodiment of this application.

[0034] The attached diagram shows the markings and corresponding component names:

[0035] 1. Chip structure; 11. Absorbing film; 12. Insulating layer; 13. Measurement circuit; 14. Thermistor; 2. Internal fixing structure; 3. Cooling pipe; 4. External protective sleeve; 5. Observation window; 6. Signal lead; 7. Aviation connector; 8. Probe. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0037] This invention provides a radiation calorimeter probe for future fusion reactors to solve the technical problems of measurement inaccuracy and maintenance difficulties caused by existing probes due to the inability of materials to withstand neutron irradiation, low signal-to-noise ratio under high temperature conditions, and lack of electromagnetic shielding.

[0038] like Figure 1 As shown, this application provides a radiation calorimeter probe for a future fusion reactor, designed to withstand the extremely harsh environment near the first wall of the fusion reactor. The probe includes an outer protective sleeve 4, a chip structure 1, an internal fixing structure 2, and cooling pipes 3.

[0039] The outer protective sleeve 4, serving as the probe's first line of defense, is made of non-magnetic stainless steel (such as 316L or 304L grade). The core reason for choosing non-magnetic stainless steel is its excellent mechanical strength to resist electromagnetic stress within the fusion reactor. Furthermore, because the fusion reactor contains extremely strong magnetic fields (typically several to tens of Tesla), using ferromagnetic materials would lead to severe magnetic disturbances or even magnetic field adsorption. Non-magnetic stainless steel effectively avoids these problems and naturally possesses a certain degree of electromagnetic shielding effectiveness. Cooling pipes 3 are built into the wall or internal space of the outer protective sleeve 4, forming an embedded flow channel or embedded coil structure. This allows for the circulation of coolant to actively regulate the probe's internal temperature, preventing the chip structure 1 from overheating and thus failing to effectively measure radiated power.

[0040] The chip structure 1, as the core sensitive element for measurement, is housed inside the outer protective sleeve 4 and is securely installed through the internal fixing structure 2. The internal fixing structure 2 can be made of insulating materials such as aluminum nitride ceramic with high thermal conductivity. Through concave-convex matching methods, such as mortise and tenon structures, wedge blocks and wedge grooves, and stepped fitting, the chip structure 1 is precisely limited and fixed to prevent displacement of the device under the strong vibration environment of the fusion reactor, which would cause the measurement position to shift.

[0041] like Figure 2As shown, chip structure 1 adopts a multi-layer composite structure, with an absorption film 11, an insulating layer 12, a measurement circuit 13, and a thermistor 14 stacked sequentially to achieve efficient absorption and electrical signal conversion of plasma thermal radiation. Bremcellous radiation is the main source of thermal radiation, with an energy range of 0.1 keV to 200 keV, primarily in the form of soft X-rays, with typical peak values ​​of 1 eV to 10 keV. The absorption film 11 needs to have a high absorptivity to effectively cover this energy range and convert radiant energy into thermal energy. The measurement circuit 13 and the thermistor 14 are integrated on the back of the insulating layer 12 and connected by gold or aluminum wire leads to achieve electrical connection between the measurement circuit and the thermistor.

[0042] This embodiment effectively withstands the high-temperature heat load of 500°C to 1200°C on the first wall of the fusion reactor and the peak heat flux of 10 to 20 MW / m² in the divertor region through the coordinated design of the non-magnetic stainless steel shell and the built-in cooling pipe 3. The neutron spectrum of the future fusion reactor will be dominated by 14.MeV fast neutrons, containing a small amount of thermal / hyperthermal neutrons; the neutron flux will be approximately 10¹. 4 up to 10¹ 5 The radiation power loss is approximately n / (cm²·s), with an annual dose of about 10 to 30 dpa (Displacement Per Atom). Radiation power loss accounts for 30% to 50% of the heating power, making it crucial for plasma energy confinement and directly affecting the accuracy of the three-product calculation in the Lawson criterion. Simultaneously, the multilayer structure design of chip structure 1 ensures the stability of material physical properties under high radiation environments, thereby guaranteeing measurement accuracy.

[0043] In one embodiment, the layout of the cooling pipe 3 is optimized for high heat flux density conditions. The cooling pipe 3 can be arranged to extend linearly along the axial direction of the outer protective sleeve 4 to form a straight flow channel, which is suitable for uniform heat load scenarios; or it can be spirally coiled around the periphery of the chip structure 1 to form a surrounding flow channel, which is suitable for local high heat flux concentration scenarios, so as to maximize the heat exchange area and improve heat exchange efficiency.

[0044] Coolant flows through cooling pipe 3, which can be selected from one or more combinations of light water, heavy water or liquid nitrogen.

[0045] Preferably, light water is used as the coolant because it is inexpensive and has a certain moderating and absorbing effect on 14MeV neutrons, which helps reduce the radiation damage to plasma components caused by neutron flux, making it suitable for cooling requirements under normal steady-state conditions. Heavy water has a better moderating and absorbing effect on neutrons and can more effectively reduce the neutron background, but its cost is significantly higher than that of light water, making it suitable for precision diagnostic areas with extremely high neutron shielding requirements. Liquid nitrogen can also be used as the cooling medium under transient high heat loads or emergency shutdown conditions.

[0046] This embodiment optimizes the spiral winding layout of the cooling pipe 3 and the coordination with the light water coolant to stably control the operating temperature of the chip structure 1 within a suitable range below 500℃, significantly improving the signal-to-noise ratio and measurement stability under high temperature conditions, and avoiding changes in the thermistor performance and increased noise in the measurement circuit caused by excessively high temperatures.

[0047] In one embodiment, the materials of the absorbing film 11, thermistor 14, and measurement circuit 13 of the chip structure 1 are optimized for neutron irradiation resistance. Since traditional gold-based materials undergo nuclear transmutation under 14 MeV neutron irradiation to generate mercury (Hg), this not only alters the thermophysical properties of the material leading to measurement inaccuracies but also causes radioactive contamination of the vacuum chamber. Therefore, neutron-resistant materials must be selected. The absorbing film 11, thermistor 14, and measurement circuit 13 are made of neutron-resistant materials, specifically selected from pure tungsten, platinum, or alloys of rhenium-tungsten, molybdenum-rhenium, and platinum-rhodium.

[0048] Specifically, the absorbing film 11 is made of tungsten. Tungsten has a high melting point of 3422℃, maintains structural stability at operating temperatures from 500℃ to 1000℃, and has a thermal conductivity of 173 W / (m·K) and a coefficient of thermal expansion of 4.5×10⁻⁻⁻⁻⁶. 6 / ℃, perfectly suited for high heat flux environments; more importantly, the transmutation products of tungsten are mainly rhenium (Re) and osmium (Os), with low activation risk, meeting the low activation requirements of fusion reactors. Thermistor 14 and measuring circuit 13 use rhenium-tungsten alloy (such as W-3Re or W-5Re), which has a thermal conductivity of approximately 90 to 140 W / (m·K) at 500℃ to 1200℃, strong resistance to helium brittleness, and stable irradiation structure. Rhenium-tungsten alloy has a melting point of approximately 3150℃ to 3380℃ and a coefficient of thermal expansion of 4.0×10⁻ 6 / ℃; compared with pure tungsten, its helium embrittlement resistance is significantly enhanced and its microstructure stability is better; it has extremely strong resistance to plasma sputtering; it has excellent dimensional stability under long-term irradiation at 500℃ to 1000℃; it has extremely low tritium retention; under 14.1 MeV neutron irradiation of fusion, the Re and Os generated by the transmutation of the tungsten matrix can be effectively dissolved by the pre-alloyed Re, inhibiting void swelling and brittle phase precipitation, and exhibiting excellent stability of microstructure and thermophysical properties at 500℃ to 1000℃ and within 30 dpa.

[0049] Preferably, the absorbing film 11 is made of tungsten material because it possesses excellent high-temperature thermosensitivity, electrical conductivity, and low activation characteristics, and its raw material cost is lower than that of platinum-based materials. Considering both price and micro / nano fabrication processes, tungsten material has significant advantages; rhenium-tungsten alloys and molybdenum-rhenium alloys are also good alternatives. Platinum has a melting point of 1772℃, exhibits no phase transition at high temperatures, and has a lattice constant and thermal expansion coefficient of approximately 9 × 10⁻⁻⁻⁻⁴. 6 / ℃, thermal conductivity 71 W / (m·K), good thermal dimensional stability, low swelling less than 30 dpa: irradiated structure is stable, neutron transmutation products Au and Ir are completely dissolved in the Pt matrix, and no brittle intermetallic phase is generated; hardening / embrittlement is controllable, low risk of helium embrittlement and low tritium retention, but the cost is high, making it suitable for extremely high precision metrological standard parts.

[0050] The melting point of molybdenum-rhenium alloy is 2480℃ to 2610℃, and its coefficient of thermal expansion is 5.4×10⁻℃ (20℃ to 1000℃). 6 / ℃ to 6.5×10⁻ 6 At 800℃, its thermal conductivity is 50 to 95 W / (m·K); it is sputter-resistant, has low tritium retention, and extremely low vacuum outgassing rate, making it suitable for high-vacuum diagnostic environments in fusion processes. However, under fusion neutron irradiation, Re rapidly transposes to Os, precipitating a brittle Mo3Os phase at approximately 5 dPa, leading to significant hardening and embrittlement, which limits its long-life applications. The platinum-rhodium alloy has a melting point of 1840℃ to 1927℃ and a thermal expansion coefficient of 7.7 × 10⁻⁻⁶ at 20℃ to 1000℃. 6 / ℃ to 8.7×10⁻ 6 At 800℃, its thermal conductivity is only 20 to 50 W / (m·K); under fusion neutron irradiation, Pt transmutates to Au and Rh transmutates to Pd to form a stable single-phase solid solution with no brittle phase precipitation and extremely low void swelling; the decay period of the activated products is controllable; it has extremely strong chemical inertness: it is resistant to plasma corrosion, oxidation, tritium penetration and retention; its high-temperature thermoelectric properties are stable, and the resistivity and thermoelectric potential change very little under irradiation, making it a core material for high-temperature thermocouples and sensor diagnostics, suitable for precision electromagnetic, temperature, and plasma parameter diagnostics; however, it is relatively expensive.

[0051] In one embodiment, the thickness of the absorbing film 11 is precisely defined to balance absorption efficiency and radiation damage. The thickness of the absorbing film 11 is set to 0.1 μm to 100 μm. This thickness range ensures efficient absorption of thermal radiation while avoiding the accumulation of neutron radiation damage or slow thermal response due to excessive thickness. Specifically, the thickness of the absorbing film 11 is preferably set to 1 μm to 100 μm. This allows for complete absorption of bremsstrahlung radiation from 1 keV to 200 keV while maintaining a rapid temperature rise response, meeting the requirements of transient measurements.

[0052] In this embodiment, by setting the tungsten absorbing film 11 to a preferred thickness of 2 μm, the structure remains stable under 14 MeV neutron irradiation without peeling or lattice distortion, and the absorption efficiency of soft X-rays from 1 keV to 100 keV is as high as 95% or more, effectively solving the measurement inaccuracy problem caused by the transmutation of traditional gold films into mercury.

[0053] In one embodiment, the material of the insulating layer 12 is optimized for multi-dimensional performance. The insulating layer 12 must simultaneously meet five core requirements: high temperature resistance (≥500℃, extreme conditions ≥1000℃), resistance to 14 MeV neutron irradiation, insulation stability, low activation, and vacuum compatibility (low outgassing rate). Specifically, it is selected from one or more combinations of diamond, silicon carbide, or silicon nitride.

[0054] The selection of insulation materials needs to be tailored to the specific operating conditions of the fusion reactor.

[0055] Diamond is suitable for short-life (1 to 5 years) insulation applications with an annual dose ≤15 dpa and temperatures ranging from 500°C to 800°C. Its extremely high room-temperature thermal conductivity (approximately 900 W / (m·K) to 2200 W / (m·K)) facilitates rapid heat dissipation, and its microstructure remains stable under these conditions, ensuring reliable insulation performance. However, when the annual dose exceeds 20 dpa, carbon atoms in the diamond lattice are prone to displacement, leading to graphitization and a sharp increase in electrical conductivity, resulting in insulation failure. Therefore, it is more suitable for insulation requirements in short-cycle fusion devices or in areas where localized, non-maximum irradiation is not the most intense.

[0056] Silicon carbide is suitable for short-to-medium life (1 to 5 years) insulation applications with an annual dose ≤15 dpa and a temperature range of 500℃ to 800℃. It exhibits high thermal conductivity and low activation. Specifically, its volume resistivity at room temperature is greater than 10¹³ Ω·cm, and its insulation resistance at 600℃ is still greater than 10¹³ Ω·cm. 0 Ω·cm; thermal conductivity at room temperature ranges from 400 W / (m·K) to 490 W / (m·K), and is approximately 200 W / (m·K) at 800℃; the coefficient of thermal expansion is 4.5 × 10⁻⁻⁻⁶ in the range of 20℃ to 1000℃. 6 / ℃ to 5.5×10⁻ 6 It exhibits excellent thermal dimensional stability at / ℃; moreover, the transmutation products contain no highly toxic heavy metals and have a low radioactive risk, making it suitable for short- to medium-term insulation requirements.

[0057] Silicon nitride is an ideal choice for long-life insulation applications, suitable for insulation components with an annual dose ≤25 dpa, a temperature range of 500℃ to 800℃, and a long lifespan (5 to 10 years). Its resistance to radiation damage is particularly outstanding, its transmutation products contain no heavy metals, and it exhibits the lowest radioactivity. Specific parameters show that silicon nitride provides insulation at room temperature, with an insulation resistance greater than 10¹² Ω·cm at 800℃; its room temperature thermal conductivity is 25 W / (m·K) to 35 W / (m·K), and approximately 15 W / (m·K) to 20 W / (m·K) at 800℃; its coefficient of thermal expansion is extremely low, only 3.0 × 10⁻⁻⁻⁶, within the temperature range of 20℃ to 1000℃. 6 / ℃ to 3.5×10⁻ 6With a temperature range of / ℃, silicon nitride exhibits excellent thermal compatibility with silicon and most metals; it also possesses a high displacement threshold energy, strong self-healing ability, shows no severe amorphization within 30 dPa, and maintains structural stability under long-term irradiation. These advantages make silicon nitride suitable for almost all fusion insulation scenarios, especially for the long-life, high-precision diagnostic insulation requirements near the first wall of fusion reactors, making it the optimal candidate material for this application.

[0058] Preferably, the insulating layer 12 is made of silicon nitride material because of its optimal comprehensive performance, which is suitable for the long-life, high-precision diagnostic requirements near the first wall of the fusion reactor. In this embodiment, by using the silicon nitride insulating layer 12, stable electrical isolation between the layers of the chip structure 1 is achieved while meeting the five core requirements, thus avoiding short circuits caused by insulation failure.

[0059] In one embodiment, the insulating layer 12 is made of silicon nitride material and is used to maintain an insulation resistance greater than 10¹² Ω·cm under operating conditions of annual dose ≤25 dpa and temperature 500°C to 800°C.

[0060] In this embodiment, by applying the silicon nitride insulating layer 12 to the above-mentioned operating conditions, the measured insulation resistance remains at an excellent level at high temperatures, and no serious structural degradation occurs after 30 dpa neutron irradiation, ensuring the insulation stability of long-term operation.

[0061] In one embodiment, the outer protective sleeve 4 is a one-piece molded structure configured to also provide electromagnetic shielding to block strong magnetic field interference within the fusion reactor. Specifically, the one-piece structure is manufactured using integral casting or seamless welding processes, with no seams, effectively preventing the penetration of external magnetic fields into the interior.

[0062] In this embodiment, the external Tesla-level strong magnetic field is attenuated to the Gauss level or below that allowed by the chip structure 1 through the integrally molded stainless steel external protective sleeve 4, thereby avoiding interference of the strong magnetic field on the weak signal of the measurement circuit 13 and improving the reliability of the measurement data.

[0063] In one embodiment, the probe is configured as an integral pluggable module, and the outer protective sleeve 4 is fixed to the first wall of the fusion reactor via a detachable connection to support complete replacement during remote operation. Specifically, the detachable connection can be secured with screws to ensure the stability and sealing of the module installation and prevent vacuum leakage.

[0064] This embodiment designs the probe as an integral pluggable module, which allows the entire probe to be removed and replaced with a new module simply by disassembling the connecting parts during remote maintenance. This eliminates the need to disassemble the internal chip structure 1 and cooling pipe 3, significantly shortening maintenance time and reducing operational difficulty, thus meeting the needs of fully remote-controlled maintenance of fusion reactors.

[0065] In one embodiment, the detachable connection is a screw fastening connection, which is simple in structure, highly reliable, and convenient for remote robotic arm operation. The outer protective sleeve 4 also has an observation window 5, which is a wedge-shaped notch used to define the incident angle of plasma thermal radiation. Specifically, the angle of the wedge-shaped notch is set according to the actual situation to cover a specific plasma area.

[0066] In this embodiment, the probe is rigidly fixed to the first wall by screw fastening, and the angle of incident thermal radiation is limited to a reasonable range by using the wedge-shaped observation window 5, which ensures the spatial resolution of the measurement data and provides accurate input for subsequent two-dimensional radiation distribution inversion.

[0067] In one embodiment, the probe further includes a signal lead-out line 6 and an aviation connector 7. One end of the signal lead-out line 6 is connected to the chip structure 1, and the other end passes through the internal fixing structure 2 and is led out through the external protective sleeve 4 to connect to the aviation connector 7. Specifically, the signal lead-out line 6 uses a high-temperature resistant and radiation-resistant coaxial cable (such as a mineral-insulated cable or a polyimide-insulated cable) to reduce signal loss and interference during transmission; the aviation connector 7 uses a vacuum-sealed connector (such as a glass-sintered seal or a ceramic seal) to ensure a stable connection between the vacuum environment inside the probe and the external circuitry.

[0068] This embodiment achieves low-noise transmission of measurement signals from chip structure 1 by using a high-temperature resistant coaxial cable in conjunction with a vacuum-sealed aviation connector 7. Even in the high radiation and high temperature environment of the fusion reactor, the signal distortion rate remains at an extremely low level, ensuring the accuracy of data acquisition.

[0069] In one embodiment, the calibration method for the probe is supplemented. Since the absorptivity of the absorbing film 11 may change with temperature and neutron irradiation, the probe needs to be periodically calibrated in situ. The calibration process includes irradiating the absorbing film 11 with a blackbody radiation source or laser heat source of known power, recording the resistance change of the thermistor 14, establishing a temperature-resistance-radiation power correlation curve, and compensating for baseline drift caused by neutron irradiation.

[0070] In practical applications, the design of this probe fully considers compatibility with existing fusion reactor diagnostic systems. The dimensions and interface specifications of the outer protective sleeve 4 conform to internationally accepted diagnostic port standards, allowing direct replacement of existing imported probes without requiring modifications to the fusion reactor structure. The signal lead 6 and aviation connector 7 are selected in accordance with nuclear-grade electronic equipment interface specifications, enabling seamless integration with mainstream data acquisition systems. Furthermore, the modular design of the probe allows for independent replacement of each component, reducing maintenance costs throughout its lifecycle. Those skilled in the art will understand that the above compatibility design is based on conventional optimizations of existing industry standards and does not alter the core technical concept of this invention, aiming to improve the product's practicality and ease of market promotion. The above compatibility design has passed interface matching tests and signal transmission verification under a laboratory simulation environment. Test results show that this probe can achieve stable communication with the control system of existing fusion reactors, and data transmission delay and bit error rate both meet design requirements. These tests are all conventional verification methods in the field and do not involve new technical methods or equipment.

[0071] This embodiment further eliminates the influence of environmental factors on measurement results by introducing a calibration mechanism, thereby improving the measurement accuracy during long-term operation.

[0072] The process steps and parameter settings involved in the above embodiments are all conventional technical means that can be conventionally implemented by those skilled in the art based on existing technology. The specific implementation details can be adaptively adjusted according to the actual operating conditions of the fusion reactor, without the need for special equipment modifications or unconventional material development that deviate from the core concept of this invention.

[0073] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A radiation calorimeter probe for a future fusion reactor, characterized in that, include: An outer protective sleeve, a chip structure disposed inside the outer protective sleeve, an internal fixing structure for fixing the chip structure, and cooling pipes; The outer protective sleeve is made of non-magnetic stainless steel, and the cooling pipe is built into the wall or internal space of the outer protective sleeve. The chip structure includes an absorption film, an insulating layer, and a measurement circuit containing a thermistor, which are stacked sequentially.

2. The radiation calorimeter probe for a future fusion reactor according to claim 1, characterized in that, The cooling pipes extend axially along the outer protective sleeve or are spirally coiled around the periphery of the chip structure. Coolant flows through the cooling pipe, and the coolant is selected from one or more combinations of light water, heavy water, or liquid nitrogen.

3. The radiation calorimeter probe for a future fusion reactor according to claim 1, characterized in that, The absorbing film, thermistor, and measuring circuit are made of neutron-resistant materials. The neutron-resistant material is selected from pure tungsten, platinum, or an alloy of rhenium-tungsten, molybdenum-rhenium, platinum-rhodium.

4. The radiation calorimeter probe for a future fusion reactor according to claim 3, characterized in that, The thickness of the absorbent film is set to be from 0.1 μm to 100 μm.

5. The radiation calorimeter probe for a future fusion reactor according to claim 1, characterized in that, The insulating layer is made of a material that simultaneously meets the requirements of high temperature resistance, 14 MeV neutron irradiation resistance, insulation stability, low activation and vacuum compatibility. The material is selected from one of diamond, silicon carbide, or silicon nitride.

6. The radiation calorimeter probe for a future fusion reactor according to claim 5, characterized in that, The insulating layer is made of silicon nitride material.

7. The radiation calorimeter probe for a future fusion reactor according to claim 1, characterized in that, The outer protective sleeve is a one-piece molded structure, which is configured to also have electromagnetic shielding function.

8. The radiation calorimeter probe for a future fusion reactor according to claim 7, characterized in that, The probe is configured as an integral pluggable module, and the outer protective cover is fixed to the first wall of the fusion reactor via a detachable connection.

9. The radiation calorimeter probe for a future fusion reactor according to claim 8, characterized in that, The detachable connection method is a screw fastening connection; The outer protective sleeve is also provided with an observation window, which is a wedge-shaped notch used to limit the incident angle of plasma thermal radiation.

10. The radiation calorimeter probe for a future fusion reactor according to claim 1, characterized in that, The probe also includes signal lead-out wires and an aviation connector; One end of the signal lead is connected to the chip structure, and the other end passes through the internal fixing structure and is led out through the external protective sleeve and connected to the aviation plug.

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