Improved front water mixing heat exchange device of TOKAMAK test system

Abstract

The invention relates to the technical field of new energy and energy conservation, in particular to a front water mixing and heat exchange device of an improved TOKAMAK test system, which comprises a water mixing and heat exchange tank and a jet pump, and a rotary jet water distribution mechanism, a shunt barrel and oblique fins for heat exchange are arranged in a sleeve on the innermost side of the water mixing and heat exchange tank. On the basis of original chilled water and chilled water loops, cooling water and the tail end pressure of the chilled water main loop are balanced from the chilled water separation injection loop, meanwhile, the cooling water is pre-cooled, and the cooling capacity of chilled water in the injection loop is fully absorbed from the cooling water separation auxiliary loop; the three main cooling loops in which cooling water and chilled water are mixed together are cooled and mixed through the improved water mixing heat exchange tank, concentrated water flow flowing into a water tank of an original device is divided into multiple water flows through the triangular weir diversion barrel, noise in the operation process of the original device is reduced, and compared with the original device, the reliability is improved, the water mixing efficiency is improved, and the service life of the device is prolonged. And the maintenance is convenient.

Description

Technical Field

[0001] The invention relates to the technical field of new energy and energy-saving technology, in particular to a pre-mixed water heat exchange device of an improved TOKAMAK test system. Background Art

[0002] Magnetic confinement controlled nuclear fusion and high temperature plasma technology is a process that utilizes two lighter atomic nuclei to fuse into a heavier atomic nucleus and release energy. The nuclear fusion reaction achieved is the fusion of hydrogen isotopes - deuterium and tritium. Magnetic confinement controlled nuclear fusion is commonly known as the artificial sun. The principle is nuclear fusion reaction, and the nuclear fusion reaction mainly relies on hydrogen isotopes (deuterium and tritium). Nuclear fusion does not produce the long-term and high-level nuclear radiation that occurs in nuclear fission, does not produce nuclear waste, does not produce greenhouse gases, and basically does not pollute the environment. Human beings' understanding of thermonuclear fusion began with the explosion of hydrogen bombs. Magnetic confinement controlled nuclear fusion and high temperature plasma devices can effectively control the process of "hydrogen bomb explosion", allowing energy to be continuously and stably output, providing people with clean energy, and are one of the future ways to replace fossil energy and be environmentally friendly.

[0003] So far, there are four countries in the world that have their own tokamak devices, France's Tore-Supra, Russia's T-15, Japan's JT-60U, and China's EAST (Fully Superconducting Tokamak Nuclear Fusion Experimental Device). In addition, there is the largest international cooperation International Thermonuclear Experimental Reactor project ITER (International Thermonuclear Experimental Reactor). Patented technology for solving the cooling of water-cooled coils of CTRFR (Compact-Tokamak based repetitive reconnection-heated Fusion Reactor, spherical tokamak compact reconnection fusion reactor) devices "An external water mixing device for TOKAMAK test device (such as Figure 1 )” The mixed water heat exchange tank in ZL 2023 2 2353372.X has the following problems: (1) The entire device has only one water mixing heat exchange tank located at the front end of the device. When the front end fails, it will directly affect the subsequent equipment, resulting in a poor water mixing effect for the entire device. (2) The horizontality of the water mixing heat exchange tank installation and whether it can be kept horizontal during operation have a great impact on the operation. A slight tilt of the tank body will directly cause the water distribution disc to tilt, resulting in uneven water distribution, which will lead to a poor water mixing effect and affect the cooling effect of the test device. After multiple tests, the temperature value measured by the temperature sensor in the coil of the test device will gradually increase. (3) During operation, the flow rate of the cooling water and chilled water outlets is unstable due to the voltage fluctuation of the power grid, the water flow state in the pipeline (the air bubbles in the water in the pipeline cannot be completely eliminated, the bubbles are compressed and reduced in volume due to the high pressure at the outlet of the water pump, and the volume of the bubbles increases due to the pressure reduction at the outlet of the device, and the cycle continues), the operation state of the water pump, and other factors, resulting in unstable flow state; (3) In the horizontal direction of the tank body, the flow rates of the cooling water and chilled water outlets are basically equal. Due to the different flow rates of cooling water and chilled water, the chilled water flow rate is 3.33 times that of cooling water, causing the recoil force of the water flow on the chilled water side to be greater than that on the cooling water side, resulting in the overall tilt of the mixed water heat exchange tank and the D16 screw that fixes the water distribution circle; (4) After the cooling water and chilled water are mixed, a water drop occurs directly. Due to the large water flow rate, the water flow impacts the bottom plate of the drop trough (3mm thick stainless steel plate) when falling, causing a relatively large noise. (5) Frequent debugging is required. After a period of normal operation after frequent debugging, the mixing effect deteriorates and needs to be debugged again. Summary of the invention

[0004] Aiming at the problem of mixed water cooling and temperature reduction of the cooling water circuit and the chilled water circuit of the water-cooling coil of the CTRFR (Compact-Tokamak based repetitive Reconnection-heated Fusion Reactor) device in the prior art, the present invention provides a pre-mixed water heat exchange device of an improved TOKAMAK test system.

[0005] The present invention is achieved through the following technical solutions: A pre-mixed water heat exchange device of an improved TOKAMAK test system comprises a mixed water heat exchange tank, a water collector and distributor, a chilled water main pipe, a chilled water branch pipe, a cooling water main pipe, a cooling water branch pipe and a jet pump; one end of the chilled water main pipe is connected to the circulating chilled water of the refrigerator, and the other end is connected to the chilled water inlet of the water collector and distributor, and the water outlet of the water collector and distributor is connected to the mixed water heat exchange tank; the cooling water main pipe is connected to the cooling water inlet of the water collector and distributor through the jet pump; The mixed water heat exchange tank includes an upper end cover, a lower end cover and a three-layer sleeve-type cylinder structure. The upper end cover and the lower end cover are respectively fixed to the top and the bottom of the cylinder structure. The cylinder structure includes a mixed water heat exchange tank inner cylinder, an intermediate cylinder and an outer cylinder that are coaxially arranged but have different diameters (both the inner diameter and the outer diameter are different). The cavities of the mixed water heat exchange tank inner cylinder and the intermediate cylinder form a mixed water heat exchange tank chilled water intermediate jacket, and the cavities of the intermediate cylinder and the outer cylinder form a mixed water heat exchange tank cooling water outer jacket; A rotary jet water distribution mechanism is provided in the inner cylinder of the mixed water heat exchange tank, and the water inlet of the rotary jet water distribution mechanism is connected with the water outlet of the water collector and distributor; The inner tube of the mixed water heat exchange tank is a double-sided enhanced convection heat exchange copper tube with pin fins on the outside and oblique fins on the inside. The water outlet of the rotating jet water distribution mechanism faces the oblique fins. A diverter cylinder with a triangular weir is arranged at the bottom of the inner cylinder of the mixed water heat exchange tank, the bottom of the diverter cylinder is connected to the water inlet end of the outlet pipe of the mixed water heat exchange tank on the lower end cover, and the outlet end of the outlet pipe of the mixed water heat exchange tank is connected to the water inlet of the water tank; the part of the diverter cylinder below the water level of the triangular weir forms a water collecting pool with the lower part of the inner cylinder of the mixed water heat exchange tank; the diverter cylinder is used to divert the water in the water collecting pool to form a triangular weir flow, and the concentrated water flow is divided into multiple streams, reducing the concentrated impact force of the water flow on the drop plate, thereby reducing the operating noise of the entire device; at the same time, the gap between the small streams in the vertical flow channel of the triangular weir is used to connect the water tank and the inner cylinder of the mixed water heat exchange tank, balance the air pressure between the water tank and the mixed water heat exchange tank, and cancel the ventilation connecting pipe installed between the mixed water heat exchange tank and the water tank in the original patent; One end of the chilled water branch pipe is connected to the upstream of the chilled water main pipe, and the other end is connected to the chilled water inlet interface of the chilled water intermediate jacket of the mixed water heat exchange tank. The ejection branch pipe of the jet pump is connected to the chilled water intermediate jacket of the mixed water heat exchange tank through the chilled water outlet interface provided on the upper end cover; One end of the cooling water branch pipe is connected to the cooling water main pipe, and the other end is connected to the cooling water inlet interface on the upper part of the cooling water outer jacket of the mixed water heat exchange tank. The cooling water outlet interface on the lower part of the cooling water outer jacket of the mixed water heat exchange tank is connected to the cooling water inlet of the manifold.

[0006] Preferably, the terminal pressure of the cooling water main is greater than the terminal pressure of the chilled water main pipe, and the chilled water flow is greater than the cooling water flow, and the diameters of the chilled water main, chilled water branch, cooling water main and cooling water branch are adjusted according to the fluid pressure loss and flow.

[0007] Preferably, a water inlet pipe of the mixing water heat exchange tank is arranged between the inner cylinder of the mixing water heat exchange tank and the water outlet of the water collector and distributor.

[0008] Preferably, the rotary jet water distribution mechanism includes a columnar rotary through-head, a plurality of elbows and a plurality of fan-shaped nozzles; the water inlet pipe of the mixed water heat exchange tank passes through the upper end cover and is connected to the columnar rotary through-head (such as a flange connection); the elbows correspond to the fan-shaped nozzles one by one, the plurality of elbows are located in the same horizontal plane, and the horizontal plane formed by the plurality of elbows is perpendicular to the axis of the inner tube of the mixed water heat exchange tank; one end of the elbow is connected to the columnar rotary through-head, and the other end is connected to the fan-shaped nozzle; the water outlet of the fan-shaped nozzle faces the oblique wing, and the fan-shaped horizontal plane of the fan-shaped nozzle is vertically arranged; the power required for the rotation of the rotary nozzle is provided by the recoil force of the fluid sprayed from the rotary nozzle, and its energy comes from the mixed fluid of cooling water and chilled water, and no external additional power is required.

[0009] Preferably, a plurality of inner oblique wings are provided, and they are in a spiral shape and arranged parallel in space.

[0010] Preferably, a plurality of outer pin fins are provided and are welded to the outer side of the inner cylinder of the mixed water heat exchange tank in a multi-layer ring form, and two adjacent layers of pin fins are arranged in a staggered manner.

[0011] Preferably, it also includes a speed sensing system, which includes a flat cylindrical NdFeB magnet, a speed sensor, a Hall sensor probe and a transmitter arranged in the speed sensor, the transmitter is located above the upper end cover, and the Hall sensor probe of the speed sensor penetrates the upper end cover and extends into the inner cylinder cavity of the mixed water heat exchange tank; the flat cylindrical NdFeB magnet is embedded in the root of the fan-shaped rotating nozzle, and the center of the flat cylindrical NdFeB magnet is on the same vertical line as the probe of the speed sensor.

[0012] Preferably, the mixed water heat exchange tank is arranged horizontally, but is allowed to be tilted within a horizontal angle of ±15‰.

[0013] A pre-mixed water heat exchange system of an improved TOKAMAK test system, comprising a main cooling circuit, an ejector circuit and an auxiliary circuit; In the main cooling circuit, cooling water and chilled water are mixed in the water collector and distributor and then enter the hollow cavity of the inner tube of the mixing water heat exchange tank. The mixed water is evenly sprinkled on the inner wall of the inner tube of the mixing water heat exchange tank through a rotating nozzle inside the cavity for mixing water heat exchange. The heat of the mixed fluid is transferred to the chilled water in the middle jacket of the chilled water of the mixing water heat exchange tank, i.e., the chilled water of the ejection circuit, through the inclined wing wall of the inner tube of the mixing water heat exchange tank. The mixed fluid after sprinkling enters the water collecting tank, where it exchanges heat with the chilled water in the middle jacket of the chilled water of the mixing water heat exchange tank again. Finally, it enters the water collecting tank at the bottom of the inner tube of the mixing water heat exchange tank, and is split by the splitter cylinder to form a triangular weir flow that flows into the water tank drop tray and enters the water tank. When the main cooling circuit is running, the middle jacket of the chilled water in the mixed water heat exchange tank in the ejector circuit is filled with chilled water, and the water flows from bottom to top; the outer jacket of the cooling water in the mixed water heat exchange tank is filled with cooling water, and the water flows from top to bottom; In the ejection loop, the chilled water in the chilled water main pipe first passes through the chilled water jacket of the mixing water heat exchange tank and then is ejected to the jet pump; the unpowered jet pump ejects the low-pressure chilled water at the end of the chilled water loop to the end of the high-pressure cooling water loop, achieving a balance between the pressure at the cooling water end and the pressure at the chilled water end, allowing the flow to proceed smoothly without backflow causing water flow obstruction in the entire system and affecting heat exchange.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The pre-mixed water heat exchange device of the improved TOKAMAK test system of the present invention is based on the original chilled water and chilled water circuits. A circuit is divided from the chilled water and cooling water terminal main pipes, and a induced circuit is divided from the chilled water, an auxiliary circuit is divided from the cooling water, and a main cooling circuit of the cooling water and chilled water is mixed together through a converging tee and a water collector and distributor. A total of three circuits are mixed and cooled through an improved mixed water heat exchange tank and convective heat exchange to maximize the use of cooling capacity. The energy of the fluid itself is used to mix the cooling water and the chilled water for multiple times and convective heat exchange; the induced chilled water and the cooling water are mixed for the first time in the jet pump, increasing the flow rate of the pipe section between the jet pump outlet and the water collector and distributor, thereby increasing the resistance of the pipe section to eliminate the extra pressure at the end of the cooling water, ensuring that the cooling water flows smoothly into the water distributor without backflow, and at the same time implementing pre-cooling of the cooling water.

[0015] The fluid after the initial mixing is mixed with the chilled water again at the confluence tee and enters the manifold; the fluid entering the manifold is sprayed into the inner tube of the mixed water heat exchange tank through the rotating nozzle, and is mixed while exchanging heat with the injected chilled water for cooling; the impact force of the fluid sprayed from the fan-shaped nozzle on the inner tube wall of the mixed water heat exchange tube tank is used to provide power for its rotation, forming a rotating fan-shaped nozzle mechanism; the rotating fan-shaped nozzle evenly spreads the liquid mixed with chilled water and cooling water on the inner wall of the inner tube of the mixed water heat exchange tank, dynamically exchanges heat with the chilled water in the middle sleeve, and after sufficient heat exchange with the inner wall, flows into the inner tube water collection pool of the mixed water heat exchange tank to be mixed, and exchanges heat with the inner wall of the inner tube of the mixed water heat exchange tank again.

[0016] The fluid that falls into the water collecting tank in the inner cylinder of the mixed water heat exchange tank after heat exchange is divided into multiple triangular weir flows through the diversion cylinder and flows into the water tank drop tank, where water drops and mixing occurs. The noise during operation of the original device is reduced, and it is easier to maintain than the original device.

[0017] When the main cooling circuit is running, the cooling water outer jacket of the mixed water heat exchange tank is filled with cooling water and flows from bottom to top, and the freezing water middle jacket of the mixed water heat exchange tank is filled with freezing water and flows from top to bottom. The cooling water and freezing water are mixed in the manifold and then enter the rotating fan-shaped nozzle. The water flows through the vertically arranged fan-shaped nozzles to form a fan-shaped surface. The water flow formed on the fan-shaped surface is spread on the oblique wings on the inner side of the inner cylinder of the mixed water heat exchange tank, effectively expanding the contact area between the water flow and the inner wall of the inner cylinder of the mixed water heat exchange tank, and at the same time, water is evenly distributed to the oblique wing surface on the inner side of the inner cylinder of the mixed water heat exchange tank. Compared with the concentrated jet water distribution, the fan-shaped nozzle water distribution has a larger water film area formed on the inner wall surface of the inner cylinder of the mixed water heat exchange tank. For the same flow rate, the water film is much thinner and has a larger area. It is easier to adhere to the inner wall of the cylinder, and the heat exchange is more sufficient. When spraying water, the recoil force generated by the inner wall facing the water flow pushes the nozzle to rotate clockwise, so as to realize the circumferential dynamic and uniform water distribution to the inner cylinder (inner surface of the cylinder heat exchange tube) of the mixed water heat exchange tank without dead angles. At the same time, the power required for the rotation of the nozzle is provided by the recoil force of the fluid sprayed from the nozzle, and its energy comes from the mixed fluid of cooling water and chilled water, without the need for external additional power.

[0018] The fan-shaped nozzle evenly distributes water on the inner oblique wing surface of the inner cylinder of the mixed water heat exchange tank. After exchanging heat with the inner surface of the cylinder heat exchange tube, the water flows into the water collecting tank along the oblique wing on the inner surface of the cylinder. During the flow process, the relative vertical falling path of the fluid becomes longer, the contact time with the cylinder wall becomes longer, and the heat exchange is sufficient.

[0019] After the fluid flowing into the water collection tank exchanges heat with the inner heat exchange structure of the inner cylinder of the mixed water heat exchange tank again, the diversion cylinder is used to disperse the fluid in the water collection tank into multiple triangular weir flows to reduce the impact of the concentrated water flow on the drop plate and reduce noise; water mixing occurs at the same time; the gaps between the small water flows in the vertical flow channel of the triangular weir flow are used to connect the water tank and the inner cylinder of the mixed water heat exchange tank, balance the air pressure between the water tank and the mixed water heat exchange tank, and eliminate the ventilation connecting pipe installed between the mixed water heat exchange tank and the water town in the original patent.

[0020] In the ejection circuit, the ejected chilled water flow ejected by the ejector pump first flows through the intermediate jacket of the chilled water in the mixed water heat exchange tank, and at the same time exchanges heat with the mixed fluid in the inner tube and the cooling water in the outer jacket of the cooling water in the mixed water heat exchange tank, thereby reducing the waste of cooling capacity. The low-pressure chilled water at the end of the chilled water circuit is ejected to the end of the high-pressure cooling water circuit by an unpowered jet pump, so that part of the chilled water and the cooling water are initially mixed in the jet pump, and the cooling water is pre-cooled. Before entering the ejection inlet main pipe of the jet pump, the ejected chilled water first passes through the intermediate jacket of the chilled water in the mixed water heat exchange tank, and simultaneously exchanges heat with the fluids in the inner tube and the outer tube in the chilled water jacket of the mixed water heat exchange tank, and then the temperature of the chilled water is increased and then sucked into the jet pump to pre-cool the cooling water.

[0021] Furthermore, the inner tube of the mixed water heat exchange tank is a detachable double-sided convection enhanced heat exchange copper tube. The oblique fins are integrated with the base tube of the heat exchange copper tube to increase the heat exchange area while reducing the thermal conductivity resistance of the heat exchange tube wall, which is beneficial to increase the heat exchange. Pin fins are welded on the outside of the base tube and arranged in a staggered manner, which increases the contact area between the tube wall and the chilled water while well disturbing the flow of cooling water, thereby enhancing the heat exchange effect. The inner heat exchange structure of the inner tube of the mixed water heat exchange tank is a spiral oblique fin, which increases the heat exchange area while reducing the thermal conductivity resistance of the tube wall. When used in conjunction with a rotary nozzle, the rotary nozzle expands the contact area between water and the inner wall. After the water contacts the inner wall, it rotates and flows down along the spiral groove of the inner wall, delaying the descent time of the water flow and increasing the contact heat exchange time between the water and the wall.

[0022] Furthermore, the speed sensing system can monitor the rotation state of the rotating nozzle. The flat cylindrical NdFeB magnet at the root of the nozzle and the Hall sensor probe of the speed sensor are on the same vertical line to form a monitoring system. When rotating, the Hall sensor probe senses the frequency of the magnet to measure the induction intensity to measure the speed. When the speed is zero or the speed drops, it indicates that the rotating nozzle is faulty. The faulty mixed water heat exchange tank is closed through the valve, and the spare mixed water heat exchange tank is opened. At the same time, the faulty mixed water heat exchange tank is repaired without affecting the normal operation of the cooling water system.

[0023] Furthermore, a certain inclination is allowed during the installation of the mixing water heat exchange tank. Within the specified inclination range, the water mixing effect of the mixing water heat exchange tank is not affected, thereby solving the problem of force imbalance in the horizontal direction of the mixing water heat exchange tank and ensuring force balance of the mixing water heat exchange tank on the horizontal plane. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural diagram of an external water mixing device used in a TOKAMAK test device in the prior art; Figure 2 An overall structural diagram of a pre-mixing device and an external mixing device of an improved TOKAMAK test system of the present invention; Figure 3 A structural diagram of a pre-mixing water device of an improved TOKAMAK test system of the present invention; Figure 4 It is a vertical cross-sectional view of a main cooling circuit water mixing heat exchange tank in a front water mixing device of an improved TOKAMAK test system of the present invention; Figure 5 It is a plan cross-sectional view of a main cooling circuit water mixing heat exchange tank in a front water mixing device of an improved TOKAMAK test system of the present invention; Figure 6 It is a diagram of the upper components of the water mixing heat exchange tank in the front water mixing device of an improved TOKAMAK test system of the present invention; Figure 7It is a top view of the upper part of the mixing water heat exchange tank in the front mixing water device of an improved TOKAMAK test system of the present invention; Figure 8 It is a diagram of the lower components of the water mixing heat exchange tank in the front water mixing device of an improved TOKAMAK test system of the present invention; Fig. 9 It is a bottom view of the lower part of the water mixing heat exchange tank in the front water mixing device of an improved TOKAMAK test system of the present invention; Fig.10 It is a top view of a rotating nozzle in a front water mixing device of an improved TOKAMAK test system of the present invention; Fig.11 It is a side view of a rotating nozzle in a front water mixing device of an improved TOKAMAK test system of the present invention; Fig.12 It is a three-dimensional structural diagram of the inner cylinder of the water mixing heat exchange tank in the front water mixing device of an improved TOKAMAK test system of the present invention; Fig.13 It is a three-dimensional structural diagram of the outer pin fins of the inner cylinder of the water mixing heat exchange tank in the front water mixing device of an improved TOKAMAK test system of the present invention; Fig.14 It is a three-dimensional structural diagram of the inner oblique wing of the inner cylinder of the mixing water heat exchange tank in the front mixing water device of an improved TOKAMAK test system of the present invention; Fig.15 It is a schematic diagram of the spiral direction when modeling the inner oblique wing of the inner cylinder of the mixing water heat exchange tank in the front mixing water device of the improved TOKAMAK test system of the present invention; Fig.16 It is a three-dimensional diagram of a triangular weir diversion cylinder in a front water mixing device of an improved TOKAMAK test system of the present invention; Fig.17 It is a structural diagram of a jet pump in a pre-mixing device of an improved TOKAMAK test system of the present invention.

[0025] In the figure, 1, chilled water backflow preventer; 2, first ball valve; 3, water collector and distributor; 4, mixing water heat exchange tank inlet butterfly valve; 5, mixing water heat exchange tank; 6, water tank; 7, second ball valve; 8, third ball valve; 9, fourth ball valve; 10, pressure gauge; 11, exhaust valve; 12, flange plug; 13, jet pump; 14, cooling water backflow preventer; 15, speed sensor; 16, nozzle; 17, NdFeB magnet; 18, probe; 19, mixing water heat exchange tank inner cylinder; 20, middle cylinder; 21, outer cylinder; 22, diverter cylinder; 23, flexible joint; 24, chilled water outlet interface; 25. Chilled water inlet interface; 26. Cooling water inlet interface; 27. Cooling water outlet interface; 28. Lower end cover; 29. ​​Upper end cover; 30. Threaded joint; 31. Upper cavity; 32. Chilled water middle jacket of mixed water heat exchange tank; 33. Cooling water outer jacket of mixed water heat exchange tank; 34. Ejector branch pipe; 35. Bimetallic thermometer; 36. Chilled water branch pipe; 37. Cooling water branch pipe; 38. Converging tee; 39. Sealing ring; 40. Water collecting tank; 41. Oblique fins; 42. Pin fins; 43. Columnar rotating head; 44. Fastening connecting screw; 45. Diverter tee; 46. Base pipe. DETAILED DESCRIPTION

[0026] The present invention is further described in detail below in conjunction with specific embodiments, which are intended to explain the present invention rather than to limit it.

[0027] The present invention discloses a pre-mixed water heat exchange device of an improved TOKAMAK test system, referring to Figure 2 , 3 , including a mixing water heat exchange tank 5, a water collector and distributor 3, a chilled water main pipe, a chilled water branch pipe 36, a cooling water main pipe, a cooling water branch pipe 37, a jet pump 13 and a rotary jet water distribution mechanism.

[0028] In one embodiment, the outlet of the chilled water main pipe is connected to the chilled water branch pipe 36 and the manifold 3 through a diverter tee 45, the diverter tee 45 is connected to the water inlet of the manifold 3 by a chilled water backflow preventer 1, and the outlet of the cooling water main pipe is connected to the water inlet of the jet pump 13 by a cooling water backflow preventer 14. The manifold is provided with a pressure gauge 10 and a bimetallic thermometer 35, and the pressure gauge 10 is provided with a shut-off valve and a gauge curve. When the entire system is stopped or running, the manifold is full of water.

[0029] One end of the chilled water main pipe is connected to an external chilled water source, and the other end is connected to the chilled water inlet of the manifold 3. The water outlet of the manifold 3 is connected to the mixed water heat exchange tank 5. The cooling water main pipe is connected to the cooling water inlet of the manifold 3 through the jet pump 13. In one embodiment, the chilled water main pipe and the jet pump 13 are connected to the manifold 3 through a converging tee 38.

[0030] Reference Figure 4 , 5 , 6, 7, 8, 9, the mixed water heat exchange tank includes an upper end cover 29, a lower end cover 28 and a three-layer sleeve-type cylinder structure, the upper end cover 29 and the lower end cover 28 are respectively fixed to the top and the bottom of the cylinder structure, specifically, the outer cylinder 21 and the middle cylinder 20 are both made of carbon steel, the upper end cover 29 and the outer cylinder 21 are welded to form a first assembly, the lower end cover 28 and the middle cylinder 20 are welded to form a second assembly, and then the first assembly and the second assembly are combined, and the inner cylinder 19, the middle cylinder 20 and the outer cylinder 21 of the mixed water heat exchange tank are compressed and sealed by the upper end cover 29, the lower end cover 28 and the annular U-shaped polytetrafluoroethylene sealing ring 39 set at both ends of each cylinder, and the compression force is provided by the fastening connection screw rod 44 passing through the circular holes on the edges of the upper and lower end covers 28 and tightening the bolts. The outer cylinder 21 and the upper end cover 29, the middle cylinder 20 and the lower end cover 28 are combined separately. This is because the expansion coefficient of carbon steel is smaller than that of copper. When the temperature changes, the elongation of the outer cylinder 21, the middle cylinder 20 and the inner cylinder 19 of the mixed water heat exchange tank is different. The effects of thermal expansion and contraction of the outer cylinder 21 and the middle cylinder 20 during system operation are offset by separate connections.

[0031] The cylinder structure includes an inner cylinder 19, an intermediate cylinder 20 and an outer cylinder 21 of a mixed water heat exchange tank which are coaxially arranged but have different diameters (outer diameter, inner diameter). The cavity between the inner cylinder 19 and the intermediate cylinder 20 of the mixed water heat exchange tank forms an intermediate jacket 32 ​​for chilled water of the mixed water heat exchange tank, and the cavity between the intermediate cylinder 20 and the outer cylinder 21 forms an outer jacket 33 for cooling water of the mixed water heat exchange tank.

[0032] One end of the chilled water branch pipe 36 is connected to the upstream of the chilled water main pipe, and the other end is connected to the chilled water inlet interface 25 of the chilled water intermediate jacket 32 ​​of the mixed water heat exchange tank. The ejection branch pipe 34 of the jet pump 13 is connected to the chilled water intermediate jacket 32 ​​of the mixed water heat exchange tank through the chilled water outlet interface 24 provided on the upper end cover 29. Among them, the chilled water inlet interface 25 and the chilled water outlet interface 24 are arranged in the longest diagonal manner in space to ensure the maximum flow path of the chilled water and ensure uniform heat exchange.

[0033] One end of the cooling water branch pipe 37 is connected to the cooling water main pipe, and the other end is connected to the cooling water inlet interface 26 on the upper part of the cooling water outer jacket 33 of the mixing water heat exchange tank, and the cooling water outlet interface 27 on the lower side of the cooling water outer jacket 33 of the mixing water heat exchange tank is connected to the cooling water inlet of the manifold 3. The cooling water inlet interface 26 and the cooling water outlet interface 27 are arranged in the longest diagonal manner in space to ensure the maximum flow path of the cooling water and ensure uniform heat exchange.

[0034] Reference Fig.10 , 11, a rotary jet water distribution mechanism is provided in the inner tube 19 of the mixed water heat exchange tank, and the water inlet of the rotary jet water distribution mechanism is connected with the water outlet of the water collector and distributor 3. Specifically, a water inlet pipe of the mixed water heat exchange tank is provided between the inner tube 19 of the mixed water heat exchange tank and the water outlet of the water collector and distributor 3, and the rotary jet water distribution mechanism includes a columnar rotary through-hole 43, a plurality of elbows and a plurality of fan-shaped nozzles 16, the elbows correspond to the fan-shaped nozzles 16 one by one, the plurality of elbows are located in the same horizontal plane, and the horizontal plane formed by the plurality of elbows is perpendicular to the central axis of the inner tube 19 of the mixed water heat exchange tank; the water inlet pipe of the mixed water heat exchange tank passes through the upper end cover 29 and is connected with the columnar rotary through-hole 43 inside the mixed water heat exchange tank, one end of the elbow is connected with the columnar rotary through-hole 43, and the other end is connected with the fan-shaped nozzle 16, and the water outlet of the fan-shaped nozzle 16 faces the oblique wing 41.

[0035] In a certain embodiment, the water inlet pipe (D109×4.5) of the mixed water heat exchange tank passes through the geometric center circle hole of the upper end cover 29 and is welded to the upper end cover 29. The lower end of the water inlet pipe is connected to the rotary joint through a threaded joint 30. In this embodiment, the cylindrical rotary joint 43 (five-way) is threadedly connected to the four fan-shaped nozzles 16 through four 90° external thread elbows.

[0036] In one embodiment, the elbow and the four rotating fan-shaped sprinklers 16 have the same material, geometric shape, and quality and are symmetrically arranged to maintain dynamic balance. During implementation, the symmetrically arranged fan-shaped sprinklers 16 are subjected to a dynamic balance test, and a shallow hole is drilled at the root of the fan-shaped sprinklers 16 to correct the dynamic balance of the entire rotating fan-shaped sprinkler 16 system.

[0037] In one embodiment, the fan-shaped nozzle 16 is made of aluminum alloy material, and the fan-shaped plane of the fan-shaped nozzle 16 is vertically arranged. For example, each mixed water heat exchange tank inner cylinder 19 is provided with four nozzles 16, which are symmetrically and evenly arranged, the water flow rate of each nozzle 16 is 9.1m³ / h, the water flow injection speed of the nozzle 16 is 6.019m / s, the diameter of the fan-shaped nozzle 16 connecting pipe is 46mm, the fan-shaped nozzle 16 water spraying effective arc length is 210mm, and the width is 2mm.

[0038] Reference Fig.12 , 13 , 14, 15, the outer side and inner side of the inner tube 19 of the mixed water heat exchange tank are respectively pin fins 42 and oblique fins 41, and the water outlet of the rotary jet water distribution mechanism faces the inner oblique fins 41.

[0039] In one embodiment, the inner cylinder 19 of the mixed water heat exchange tank is a detachable double-sided convection enhanced heat exchange copper tube. For example, the inner cylinder 19 of the mixed water heat exchange tank is formed by lathe internal boring of a copper base tube 46 with an outer diameter of 610 mm and a wall thickness of 6 mm.

[0040] In one embodiment, a plurality of inner oblique wings 41 are provided, and are arranged in parallel in a spiral shape (the spiral direction is as follows: Fig.15The yellow line in the middle shows the heat exchange area, which increases the heat transfer area and reduces the thermal conductivity resistance of the tube wall. The rotating nozzle 16 expands the contact area between the water and the inner wall when distributing water in rotation. After the water contacts the inner wall, it flows down along the spiral groove of the inner wall in rotation, delaying the falling time of the water flow and increasing the contact and heat exchange time between the water and the wall. For example, there are 356 oblique wings, with a pitch of 680mm, a wing height of 4mm, a wing width of 5mm, a tooth top circle diameter of 598mm, a tooth root circle diameter of 606mm, and an inner tube outer diameter of 610mm. At the same time, the oblique wings 41 are processed integrally with the heat exchange copper base tube 46, which increases the heat exchange area while reducing the thermal conductivity resistance of the heat exchange tube, which is beneficial to increase the heat exchange amount.

[0041] In one embodiment, the outer pin fins 42 are knife-shaped and are provided in a plurality of them. These pin fins are arranged in groups in a multi-layer ring shape on the outer side of the inner cylinder 19 of the mixed water heat exchange tank. The adjacent two layers of pin fins are arranged in a staggered manner, which strengthens the disturbance of the water flow in the chilled water intermediate jacket 32 ​​of the mixed water heat exchange tank, and increases the heat exchange area. For example, a single pin fin is welded to the outer cylinder wall, the pin fin 42 has a wing height of 44mm, a wing width of 16mm, and a wing thickness of 2mm, 68 fins per row in the circumferential direction, and a spacing of 20mm per row in the axial direction, with a total of 32 rows, and the fins are arranged in a staggered manner, and the fins of the latter row cover the fin root gap of the fins of the previous row along the axial orthographic projection.

[0042] After the cooling water and the chilled water are mixed in the water collector and distributor 3, they enter the rotating fan-shaped nozzle 16 through the water inlet pipe and the elbow of the mixed water heat exchange tank. The water flows in the vertical direction to form a fan-shaped surface for spraying, effectively expanding the contact area between the water flow and the inner wall of the inner tube 19 of the mixed water heat exchange tank, and at the same time, evenly distributing water to the oblique wing surface of the inner wall of the inner tube. Compared with the concentrated jet water distribution, the water film formed on the inner wall surface of the mixed water heat exchange tank inner tube 19 by the fan-shaped nozzle 16 is larger. The water film with the same flow rate becomes thinner and is easier to adhere to the inner wall of the tube, and the heat exchange is more sufficient. When spraying water, the recoil force generated by the inner wall against the water flow pushes the nozzle 16 to rotate clockwise, realizing even water distribution without dead angles on the circumferential surface of the inner tube 19 (the inner surface of the cylinder heat exchange tube) of the mixed water heat exchange tank. The fan-shaped nozzle 16 evenly distributes water on the inner wall surface (inside the cylinder heat exchange tube) of the inner cylinder 19 of the mixed water heat exchange tank. After exchanging heat with the inner surface of the cylinder heat exchange tube, the water flows into the water collecting tank 40 of the inner cylinder 19 of the mixed water heat exchange tank along the inclined wings. During the flow process, the relative vertical falling path of the fluid becomes longer, the contact time with the cylinder wall becomes longer, and the heat exchange is sufficient.

[0043] In one embodiment, referring to Figure 4, and also includes a speed sensing system, which includes an oblate cylindrical NdFeB magnet 17, a speed sensor 15, a Hall sensor probe 18 and a transmitter arranged in the speed sensor 15. The transmitter is located above the upper end cover 29, and the Hall sensor probe 18 of the speed sensor 15 penetrates the upper end cover 29 and extends into the cavity of the inner tube 19 of the mixed water heat exchange tank; the oblate cylindrical NdFeB magnet 17 is embedded in the root of the fan-shaped rotating nozzle 16, and the center of the oblate cylindrical NdFeB magnet 17 is on the same vertical line as the probe 18 of the speed sensor 15. When rotating, the Hall sensor probe 18 senses the frequency of the magnetic lines of force emitted by the magnet to measure the speed. When the speed is zero or the speed drops, it indicates that the rotating nozzle 16 is faulty, and the standby mixed water heat exchange tank is started, and the faulty mixed water heat exchange tank is repaired at the same time, which does not affect the use.

[0044] One end of the chilled water branch pipe 36 is connected to the chilled water main pipe, and the other end is connected to the bottom of the middle jacket. The ejection branch pipe 34 of the jet pump 13 is connected to the middle jacket through the chilled water outlet interface 25 provided on the upper end cover 29; one end of the cooling water branch pipe 37 is connected to the cooling water main pipe, and the other end is connected to the upper part of the external jacket. A cooling water outlet interface 27 is provided at the bottom of the external jacket to communicate with the cooling water inlet of the manifold 3.

[0045] Reference Figure 4 The space of the inner cylinder 19 of the mixed water heat exchange tank is recorded as an upper cavity 31 and a lower water collection tank 40 according to the setting structure. The upper cavity 31 not only provides a working space for the nozzle 16 to rotate and distribute water to the inner cylinder wall, but also provides conditions for measuring the rotation speed of the rotating nozzle 16 to monitor its operating state. The lower water collection tank 40 and the diversion cylinder 22 provide necessary working conditions for multiple thin-walled triangular weir flows, and can also exchange heat with the chilled water jacket of the mixed water heat exchange tank for the second time, and also provide a guarantee for the normal operation of the mixed water heat exchange tank when it is tilted.

[0046] Reference Figure 8 , 15 A diverter cylinder 22 in the form of a triangular weir is provided at the lower part of the inner cylinder 19 of the mixed water heat exchange tank. The bottom of the diverter cylinder 22 is connected to the outlet pipe of the mixed water heat exchange tank on the lower end cover 28, and the outlet pipe of the mixed water heat exchange tank is connected to the water inlet of the water tank 6; the part of the diverter cylinder 22 below the triangular weir forms a water collecting pool 40 with the lower part of the inner cylinder 19 of the mixed water heat exchange tank.

[0047] In one embodiment, referring to Fig.16, 25 triangular grooves are set on the top of the diversion cylinder 22, forming a total of 25 triangular weir flows, with a wall thickness of 2mm, a triangular weir angle of 38.483°, a maximum head on the weir of 0.2m, a maximum design flow rate of each weir of 3.00m³ / h, and an actual flow rate of 1.456m³ / h. A thin-walled triangular weir is used in the mixed water heat exchange tank to disperse a concentrated water flow into 25 small-flow water flows, reducing the impact of the concentrated water flow on the drop tray and reducing noise. The triangular diversion cylinder 22 is used to penetrate into the inner cylinder 19 of the mixed water heat exchange tank, and the water sprayed by the rotating nozzle 16 is collected at the lower part of the inner cylinder 19 of the mixed water heat exchange tank to form a water collection pool 40. After the water collected in the water collection pool 40 is subjected to secondary heat exchange with the intermediate chilled water jacket, it is diverted through the triangular weir and flows into the outlet pipe of the mixed water heat exchange tank, and then falls to the drop tray of the external water tank 6.

[0048] In a certain embodiment, the outlet pipe (D133×4.5) of the mixed water heat exchange tank passes through the geometric center circular hole of the lower end cover 28 and is welded to the lower end cover 28. The outlet pipe of the mixed water heat exchange tank is threadedly connected to the triangular weir diversion cylinder 22 through a flexible joint 23. Part of the inlet and outlet pipes, the rotating fan-shaped nozzle 16, the flexible joint 23 and the triangular weir diversion cylinder 22 are all arranged inside the inner cylinder 19 of the mixed water heat exchange tank.

[0049] When the main cooling circuit is in operation, the middle jacket 32 ​​of the mixed water heat exchange tank chilled water is filled with chilled water, and the water flows from bottom to top; the outer jacket 33 of the mixed water heat exchange tank cooling water is filled with cooling water, and the water flows from top to bottom. The chilled water in the middle jacket 32 ​​of the mixed water heat exchange tank chilled water is countercurrently exchanged with the mixed fluid in the inner cylinder 19 of the mixed water heat exchange tank and the cooling water in the outer jacket 33 of the mixed water heat exchange tank cooling water. The terminal pressure of the cooling water main pipe is greater than the terminal pressure of the chilled water main pipe, and the chilled water flow rate is greater than the cooling water flow rate. The diameters of the chilled water main pipe, the chilled water branch pipe 36, the cooling water main pipe, and the cooling water branch pipe 37 are adjusted according to the fluid pressure loss and flow rate.

[0050] In one embodiment, the mixed water heat exchange tank is arranged horizontally, but the allowable inclination angle is within 15‰.

[0051] In a certain embodiment, the pre-mixed water heat exchange device of the improved TOKAMAK test system is provided with three mixed water heat exchange tanks, three sets of ejection circuits and auxiliary circuits, two of which are in operation and the other is in standby. The standby mixed water heat exchange tank is arranged between the two operating mixed water heat exchange tanks, and the ejection circuit and auxiliary circuit connected to the standby mixed water heat exchange tank are also in standby. The standby mixed water heat exchange tank and the ejection circuit and auxiliary circuit connected to it can be operated by only opening the corresponding valves, thereby ensuring the continuous operation of the entire mixed water heat exchange device. Capital letters A, B, and C are used to distinguish each mixed water heat exchange tank and the related connecting valves. The faulty circuit can be disassembled and repaired by only opening the corresponding valves. The standby mixed water heat exchange tank is activated by the simple operation of closing and opening the valve, thereby ensuring that the mixed water system operates normally during fault inspection and repair without affecting the mixing effect; it is easier to maintain than the original device.

[0052] The pre-mixed water heat exchange device of an improved TOKAMAK test system of the present invention forms three circuits: a main cooling circuit, an ejection circuit and an auxiliary circuit. The chilled water branch pipe 36 is connected to the chilled water main pipe, and the outlet end of the chilled water branch pipe 36 is connected to the chilled water inlet interface 25 of the intermediate jacket through the first pipe, and the first ball valve 2 is arranged on the first pipe; the chilled water outlet interface 24 of the intermediate jacket is connected to the ejection branch pipe 34 of the jet pump 13 through the third pipe, and the third ball valve 8 is arranged on the third pipe. The chilled water main pipe is connected to a chilled water pressure gauge 10, and the cooling water main pipe, the chilled water main pipe and the manifold are all provided with pressure gauges 10, so as to monitor and adjust the flow in real time. The manifold is provided with an exhaust valve 11, and the ejection branch pipe is provided with a flange plug.

[0053] The diameter of the chilled water branch pipe 36 is D57×3.5, the diameter of the chilled water main pipe is D133×4, the diameter of the cooling water branch pipe 37 is D38×2.5, the diameter of the cooling water main pipe is D76×3.5, and the specifications of the inner cylinder 19 of the mixed water heat exchange tank are D610×6, the specifications of the intermediate cylinder 20 are D712×6, and the specifications of the outer cylinder 21 are D762×6. The heights of the inner cylinder 19, the intermediate cylinder 20, and the outer cylinder 21 of the mixed water heat exchange tank are 645mm, 650mm, and 650mm respectively. The thickness of the chilled water jacket is 45mm, and the thickness of the cooling water jacket of the mixed water heat exchange tank is 20mm.

[0054] Reference Figure 2 , 3, the terminal pressure of cooling water (17.0mH2O) is greater than the terminal pressure of chilled water (10.3mH2O), and the cooling water flow rate (16.8m³ / h) is less than the chilled water flow rate (56m³ / h). In order to ensure that both chilled water and chilled water can enter the manifold 3, it is necessary to ensure that the pressures of chilled water and chilled water are basically equal when they enter the manifold 3, that is, the terminal pressure is balanced. (1) The low-pressure and high-flow chilled water is injected through the pipeline by the unpowered jet pump 13 to the high-pressure cooling water terminal for initial mixing. The flow rate of the mixed water increases, and the increase in flow rate causes the resistance between the outlet of the jet pump 13 and the manifold 3 to increase. The opening of the third ball valve 8 on the injection circuit can adjust the flow rate of chilled water to balance the outlet pressure of cooling water and chilled water at the manifold 3, so that it can flow smoothly into the manifold 3. (2) At the same time, the starting point of the water flow in the ejector pipe (relative to the ground height of 6.86m) and the end point (relative to the ground height of 4.63m, i.e., the ejector pump inlet height) maintain a height difference of 2.23m. During ejection, the chilled water uses gravity to provide part of the power to cooperate with the ejection power to enter the ejector pump. The height difference between the ejector pump outlet and the inlet of the manifold 3 is also maintained at 2.23m. Gravity is used again to reduce the pressure of the chilled water and cooling water mixed by the jet pump 13 to ensure smooth water flow in the entire system.

[0055] The above-mentioned flow process is accompanied by heat exchange. Before the injected chilled water enters the injection branch pipe 34 of the injection inlet of the jet pump 13, it first passes through the middle jacket 32 ​​of the mixed water heat exchange tank - the chilled water jacket. The injected chilled water in the middle jacket 32 ​​of the mixed water heat exchange tank and the fluid flowing through the inner cylinder 19 and the outer cylinder 21 of the mixed water heat exchange tank simultaneously countercurrently strengthen the heat exchange. After the temperature of the chilled water is increased, it is sucked into the jet pump 13 to prevent the periodic sudden cooling of the two fluids in the jet pump 13 from causing thermal stress in the jet pump 13, thereby extending the life of the jet pump 13 and the pipeline.

[0056] Reference Fig.17 In this embodiment, the jet pump 13 has a throat-to-nozzle area ratio of m=2.167, a throat-to-nozzle distance of 17 mm, a fluid density ratio of 1.0, a fluid pressure ratio and a flow ratio relationship of h=0.5864-0.4209q, a design pressure ratio of 0.448, and an ejection ratio of 0.329; the design ejection flow rate is 5.27 m³ / h.

[0057] In the auxiliary circuit, the cooling water inlet main pipe is connected with the cooling water branch pipe 37, and the water outlet end of the cooling water branch pipe 37 is connected with the cooling water inlet interface 26 of the external cylinder 21 through a second pipe, and a second ball valve 7 is arranged on the second pipe. The water inlet end of the cooling water branch pipe 37 is located between the water inlet end of the jet pump 13 and the water outlet end of the cooling water main pipe, and the cooling water outlet interface 27 of the external cylinder 21 is connected with the water inlet of the manifold 3 through a fourth pipe, and a fourth ball valve 9 is arranged on the fourth pipe.

[0058] Among them, the main cooling circuit includes a chilled water main, a cooling water main, a fluid pipeline after the chilled water and cooling water are mixed, and its accessories. The accessories of the mixed fluid pipeline are specifically a mixed water heat exchange tank, a water collector and distributor 3 and corresponding valves arranged on the cooling pipeline.

[0059] The chilled water circulation pipeline in the main cooling circuit includes a chilled water main pipe and a chilled water branch pipe 36, and the cooling water circulation pipeline includes a cooling water main pipe and a cooling water branch pipe 37. The cooling water main pipe is connected to a jet pump 13. After the cooling water and the chilled water are mixed in the confluence tee 38 and the water collector and distributor 3, they enter the hollow cavity of the inner cylinder of the mixed water heat exchange tank from the main cooling circuit, and are evenly sprinkled on the inner wall of the inner cylinder 19 of the mixed water heat exchange tank through the rotating nozzle 16 inside the cavity for mixed water heat exchange, and the heat of the mixed water fluid is transferred to the chilled water in the middle jacket 32 ​​of the chilled water of the mixed water heat exchange tank, that is, the chilled water of the ejection circuit, through the wall of the inner cylinder. The mixed fluid after being sprinkled enters the water collection tank 40, and exchanges heat with the chilled water in the middle jacket 32 ​​of the chilled water of the mixed water heat exchange tank again in the water collection tank 40, and then enters the water collection tank 40 at the lower part of the inner cylinder 19 of the mixed water heat exchange tank, and enters the water drop tray of the water tank 6 through the triangular weir diversion tube and flows into the water tank 6.

[0060] The function of the ejection circuit is to achieve pressure balance of the cooling water and chilled water terminal pipelines. Specifically, the ejection circuit first ejects the chilled water in the chilled water main pipeline through the chilled water jacket of the mixing water heat exchange tank and then to the ejector pump 13. The main function of the ejector pump 13 is to balance the pressure at the end of the cooling water and chilled water main circuits, ensure the smooth flow of water in the entire system, assist in cooling, and pre-cool the cooling water. The auxiliary circuit is used to absorb the heat dissipation of the chilled water in the ejection circuit. The flow rate of the cooling water in the auxiliary circuit shall not be greater than 20% of the flow rate of the chilled water in the ejection circuit, so as to avoid causing pressure imbalance at the end of the chilled water and cooling water main circuits.

[0061] During operation, the cooling water and chilled water of the main circuit first enter the converging tee 38 and then enter the manifold 3 to form a mixed fluid. The mixed fluid flows into the rotating fan-shaped nozzle 16 in the upper cavity 31 of the inner tube 19 of the mixed water heat exchange tank through the water inlet pipe. The mixed chilled water and cooling water are evenly spread on the inner wall of the inner tube 19 of the mixed water heat exchange tank through the rotating fan-shaped nozzle 16. The recoil force generated by the inner wall facing the water flow during water spraying provides power to drive the nozzle 16 to rotate continuously clockwise; the water flow is in the vertical direction. The fan-shaped surface is enlarged, and the nozzle 16 rotates continuously to achieve uniform water distribution to the inner wall of the inner cylinder 19 of the mixed water heat exchange tank (the inner surface of the cylinder heat exchange tube) in an annular direction without dead angles, effectively expanding the contact area between the water flow and the inclined wing 41, and at the same time, uniformly distributing water to the inclined wing surface of the inner wall of the inner cylinder. Compared with the concentrated jet nozzle 16, the water film formed on the inner wall of the inner cylinder 19 of the mixed water heat exchange tank by the fan-shaped nozzle 16 is larger. The area of ​​the thin water film with the same flow rate is enlarged, and it is easier to adhere to the inner wall of the cylinder, and it is easier to exchange heat. The rotating fan-shaped nozzle 16 evenly distributes water on the surface of the inner wall (the inner wall of the cylinder heat exchange tube) of the inner cylinder 19 of the mixed water heat exchange tank to form a water film. After the initial heat exchange with the inclined wing 41, it flows into the inner cylinder water collection pool 40 along the spiral inclined wing 41 on the inner surface of the cylinder. During the flow process, the relative vertical falling path of the fluid becomes longer, and the contact time with the cylinder wall becomes longer, and the heat exchange is sufficient.

[0062] After the water is spread and exchanges heat with the inner wall oblique wing surface and the chilled water in the middle chilled water jacket, it falls into the water collection tank 40. After a second heat exchange with the chilled water middle jacket 32 ​​of the mixed water heat exchange tank in the water collection tank 40, it passes through the diverter cylinder 22 to form multiple triangular weir flows, flows into the outlet pipe of the mixed water heat exchange tank, and then falls into the water drop tray of the external water tank 6. Among them, the diverter cylinder 22 disperses the fluid in the water collection tank 40 into multiple small-flow water flows to reduce the impact force of the concentrated water flow on the water drop tray, reduce noise, and mix water drops at the same time; the gaps between the small water flows in the vertical flow channel of the triangular weir flow are used to connect the water tank 6 and the inner cylinder 19 of the mixed water heat exchange tank, balance the air pressure between the water tank 6 and the mixed water heat exchange tank, and cancel the ventilation connection pipe installed between the mixed water heat exchange tank and the water town in the original patent.

[0063] The present invention includes a pre-mixed water heat exchange device including an improved TOKAMAK test system, which uses the energy of the fluid itself to mix cooling water and chilled water for multiple times; the ejected chilled water and cooling water are mixed in the jet pump 13, which can achieve pressure balance between the cooling water and chilled water terminals and pre-cooling of the cooling water; the fluid after the initial mixing is mixed with the chilled water again at the confluence tee 38 and enters the manifold 3; the fluid entering the manifold 3 is sprayed to the inner tube 19 of the mixed water heat exchange tank through the rotating nozzle 16, and heat exchange and cooling are carried out with the ejected chilled water while mixing; the rotating nozzle 16 evenly spreads water on the wall of the inner tube 19 of the mixed water heat exchange tank, and then falls into the water collection tank of the inner tube 19 of the mixed water heat exchange tank for mixing; the fluid falling into the water collection tank of the inner tube 19 of the mixed water heat exchange tank is divided into multiple streams through the triangular weir and flows into the water tank 6 drop tank, and water drop mixing occurs. The noise of the original device during operation is reduced, and it is easier to maintain than the original device. While eliminating the ventilation connection pipe, it will not cause pressure imbalance in the water tank 6 and the water mixing heat exchange tank. When the flow rate of cooling water and chilled water changes due to changes in various factors such as grid voltage fluctuations, water flow state in the pipeline, and water pump operation state during operation, the improved water mixing device will not affect the water mixing effect of the water mixing heat exchange tank.

[0064] Taking the pre-mixing water device of a certain improved TOKAMAK test system as an example, the use conditions of the pre-mixing water device of the improved TOKAMAK test system of the present invention are: (1) The cooling water inlet temperature of the water-cooling coil of the CTRFR device is higher than the ambient wet-bulb temperature; (2) The cooling water of the CTRFR device is cooled by a commercial air-cooling module (the inlet and outlet water temperature difference is 5°C, and the inlet and outlet water temperature fluctuation is within ±2°C) as the cooling source.

[0065] (3) CTRFR device operating conditions and requirements ①The CTRFR device is powered by an electrolytic capacitor bank with a capacity of 7200F. When the charging voltage reaches 120V, the capacitor bank supplies power to the electromagnetic coil during the test. The test ends after 5s, and the device is charged again and tested again after 600s. The test device operates during the whole year. The maximum discharge energy of the capacitor bank to the CTRFR device in 5s is 51.84MJ, the average heat release rate in 5s is 10.368MW, the average heat release rate in 540.5s is 95.91kW, and the average heat release rate in 600s is 86.40kW.

[0066] ② The best cooling water inlet temperature is 20℃, and the maximum allowable change in inlet temperature is ±5℃. The water temperature entering the test equipment should be as constant as possible; when the cooling water inlet temperature is 20℃, the maximum cooling water outlet temperature shall not be higher than 100℃.

[0067] ③ The cooling water is finally collected from multiple cooling channels to the inlet and outlet main pipes, with a total cooling water flow rate of 220.14L / min; the cooling water inlet pressure is 1.0MPa, the outlet pressure is 0.2MPa, and the inlet and outlet pressure difference is 0.8MPa (cooling water terminal pressure). The total cooling water flow rate and the water flow rate allocated to each cooling channel must be accurate.

[0068] ④ Cooling water quality and resistivity index: 0.5~1MΩ·cm deionized water.

[0069] The operation of the mixed water heat exchange tank 5A is taken as an example to explain its operation principle. During operation, the chilled water circulation pump is turned on first, i.e., the chilled water circuit circulates first, and then the cooling water circulation pump is turned on, i.e., the cooling water circuit circulates last; the cooling water mixing device is provided with three end-to-end parallel circuits: the ejector circuit, the auxiliary circuit and the main cooling water mixing circuit, and each circuit works as follows: 1. Ejection circuit (1) Flow: Since the pressure of the chilled water used for cooling (10.3mH2O) is lower than the pressure of the cooling water (17.0mH2O), the chilled water flow rate (56m³ / h) is greater than the cooling water flow rate (16.8m³ / h), the jet pump injects a certain amount of chilled water (designed injection water flow rate: 5.27m³ / h) from the chilled water branch pipe to the jet pump inlet main pipe. The chilled water flows through the first valve 2A, the chilled water intermediate jacket of the mixing water heat exchange tank, the injection branch pipe, and enters the jet pump to mix with the cooling water for the first time. After mixing, it enters the manifold. The pressure of the cooling water circuit and the chilled water circuit is balanced by adjusting the injection water (chilled water) volume.

[0070] (2) Heat exchange: After the chilled water exchanges heat with the inner and outer cylinders of the mixed water heat exchange tank in the middle jacket of the chilled water, the chilled water exchanges heat with the inner cylinder and the outer cylinder at the same time, with the heat exchange in the inner cylinder being the main process. The heat exchange in the outer cylinder is mainly to make full use of the coldness of the chilled water to prevent the heat from being lost to the environment. The chilled water then enters the jet pump and mixes with the cooling water for the first time to pre-cool the cooling water, thereby preventing the cooling water temperature in the pipeline from periodically changing dramatically, causing thermal expansion and contraction of the pipeline, and generating periodic internal stress, causing metal fatigue of the pipeline and shortening its service life. 2. Auxiliary circuit (1) Flow: The cooling water pressure (17.0 mH2O) is higher than the chilled water pressure (10.3 mH2O). A small amount of cooling water (0.8 m³ / h) enters the cooling water jacket of the mixed water heat exchange tank through the second ball valve 7 through the pipeline - the fourth ball valve 9 - and enters the manifold 3; after being mixed with the chilled water in the manifold, it enters the rotating nozzle 16 in the inner cylinder of the mixed water heat exchange tank.

[0071] (2) Heat exchange: After the cooling water exchanges heat between the outer cylinder of the mixed water heat exchange tank and the intermediate jacket, it enters the manifold 3 and mixes with the chilled water. This circuit is mainly used to absorb the excess cold of the chilled water to avoid waste of cold; 3. Main cooling circuit - chilled water and cooling water mixed water heat exchange circuit After the chilled water and cooling water are mixed for the first time through the confluence tee, they enter the water collector 3 and mix again. Then, the mixed fluid enters the four fan-shaped nozzles 16 of the inner cylinder of the mixed water heat exchange tank 5 through the butterfly valve 4 of the mixed water heat exchange tank inlet. The fan-shaped rotating nozzles 16 dynamically and evenly distribute water to the inner surface of the inner cylinder 19 of the mixed water heat exchange tank. After fully exchanging heat with the chilled water in the middle jacket, it flows into the inner cylinder water collection tank of the mixed water heat exchange tank and exchanges heat with the chilled water in the middle jacket again. The water in the inner cylinder water collection tank is divided into 25 streams by the triangular weir diversion cylinder 22 and enters the internal water drop tray of the water tank 6.

[0072] The fan-shaped rotating nozzle 16 sprays water onto the inner surface of the heat exchange tube of the inner cylinder 19 of the mixed water heat exchange tank. At the same time, the water flow sprayed onto the inner surface of the heat exchange tube generates an impact force, which pushes the rotating nozzle 16 to rotate clockwise, and evenly distributes the water on the inner surface of the inner cylinder heat exchange tube. After heat exchange with the inner surface of the cylinder heat exchange tube, the water flows into the inner cylinder water collection tank 40.

[0073] II Operation status monitoring There are four rotating fan-shaped nozzles in the mixing water heat exchange tank 5A. A flat cylindrical NdFeB magnet is embedded at the root of each rotating fan-shaped nozzle. The center of the cylindrical NdFeB magnet is on the same vertical line as the upper speed sensor Hall sensor probe 18. When rotating, the Hall sensor probe senses the magnet to measure the speed. When the speed is zero, it indicates that the rotating nozzle is faulty, and the standby mixing water heat exchange tank 5C is started.

[0074] The invention also discloses an improved TOKAMAK (Tokamak) test system comprising a front-placed mixed water heat exchange device of the improved TOKAMAK test system.

[0075] The above description is only a preferred embodiment of the present invention and is not intended to impose any limitation on the technical solution of the present invention. Those skilled in the art should understand that, without departing from the spirit and principles of the present invention, the technical solution can also be subjected to several simple modifications and substitutions, and these modifications and substitutions are also within the scope of protection covered by the claims.

Claims

1. A pre-mixed water heat exchange device for an improved TOKAMAK test system, characterized in that: It comprises a mixed water heat exchange tank (5), a water collector (3), a chilled water main pipe, a chilled water branch pipe (36), a cooling water main pipe, a cooling water branch pipe (37) and a jet pump (13); one end of the chilled water main pipe is connected to the circulating chilled water of the refrigerator, and the other end is connected to the chilled water inlet of the water collector (3); the water outlet of the water collector (3) is connected to the mixed water heat exchange tank (5); the cooling water main pipe is connected to the cooling water inlet of the water collector (3) through the jet pump (13); The mixed water heat exchange tank comprises an upper end cover (29), a lower end cover (28) and a three-layer sleeve-type cylinder structure, wherein the upper end cover (29) and the lower end cover (28) are respectively fixed to the top and the bottom of the cylinder structure, and the cylinder structure comprises a coaxial but different diameter inner cylinder (19), an intermediate cylinder (20) and an outer cylinder (21) of the mixed water heat exchange tank, the cavity of the inner cylinder (19) and the intermediate cylinder (20) of the mixed water heat exchange tank forms a mixed water heat exchange tank chilled water intermediate jacket (32), and the cavity of the intermediate cylinder (20) and the outer cylinder (21) forms a mixed water heat exchange tank cooling water outer jacket (33); A rotary jet water distribution mechanism is provided in the inner cylinder (19) of the mixed water heat exchange tank, and the water inlet of the rotary jet water distribution mechanism is connected to the water outlet of the water collector and distributor (3); The inner tube (19) of the mixed water heat exchange tank is a double-sided enhanced convection heat exchange copper tube with pin fins (42) on the outside and oblique fins (41) on the inside, and the water outlet of the rotary jet water distribution mechanism faces the oblique fins (41); A triangular weir flow diversion cylinder (22) is arranged at the lower part of the inner cylinder (19) of the mixed water heat exchange tank. The bottom of the diversion cylinder (22) is connected to the water inlet end of the water outlet pipe of the mixed water heat exchange tank on the lower end cover (28). The water outlet end of the water outlet pipe of the mixed water heat exchange tank is connected to the water inlet of the water tank (6). The part of the diversion cylinder (22) below the triangular weir water level forms a water collecting pool (40) with the lower part of the inner cylinder (19) of the mixed water heat exchange tank. One end of the chilled water branch pipe (36) is connected to the upstream of the chilled water main pipe, and the other end is communicated with the chilled water inlet interface (25) at the bottom of the chilled water intermediate jacket (32) of the mixed water heat exchange tank. The ejection branch pipe (34) of the jet pump (13) is communicated with the chilled water intermediate jacket (32) of the mixed water heat exchange tank via the chilled water outlet interface (24) provided on the upper end cover (29); One end of the cooling water branch pipe (37) is connected to the cooling water main pipe, and the other end is communicated with the cooling water inlet interface (26) at the top of the cooling water outer jacket (33) of the mixing water heat exchange tank. The cooling water outlet interface (27) at the bottom of the cooling water outer jacket (33) of the mixing water heat exchange tank is communicated with the cooling water inlet of the manifold (3).

2. The pre-mixed water heat exchange device of the improved TOKAMAK test system according to claim 1 is characterized in that: The terminal pressure of the cooling water main pipe is greater than the terminal pressure of the chilled water main pipe, and the chilled water flow rate is greater than the cooling water flow rate. The pipe diameters of the chilled water main pipe, the chilled water branch pipe (36), the cooling water main pipe, and the cooling water branch pipe (37) are adjusted according to the fluid pressure loss and flow rate.

3. The pre-mixed water heat exchange device of the improved TOKAMAK test system according to claim 1 is characterized in that: A water inlet pipe of the mixed water heat exchange tank is arranged between the inner cylinder (19) of the mixed water heat exchange tank and the water outlet of the water collector and distributor (3).

4. The pre-mixed water heat exchange device of the improved TOKAMAK test system according to claim 3 is characterized in that: The rotary jet water distribution mechanism comprises a columnar rotary through-hole (43), a plurality of bent pipes and a plurality of fan-shaped nozzles (16); the water inlet pipe of the water mixing heat exchange tank passes through the upper end cover (29) and is connected to the columnar rotary through-hole (43); the bent pipes correspond to the fan-shaped nozzles (16) one by one; the plurality of bent pipes are located on the same horizontal plane, and the horizontal plane formed by the plurality of bent pipes is perpendicular to the axis of the inner tube (19) of the water mixing heat exchange tank; one end of the bent pipe is connected to the columnar rotary through-hole (43), and the other end is connected to the fan-shaped nozzle (16); the water outlet of the fan-shaped nozzle (16) faces the oblique wing (41), and the fan-shaped horizontal plane of the fan-shaped nozzle (16) is arranged vertically; The rotational power of the rotary nozzle is provided by the recoil force of the fluid sprayed from the rotary nozzle, and its energy comes from the mixed fluid of cooling water and chilled water, without the need for additional external power.

5. The pre-mixed water heat exchange device of the improved TOKAMAK test system according to claim 1 is characterized in that: A plurality of oblique wings (41) are provided on the inner side, and are arranged in parallel in a spiral shape.

6. The pre-mixed water heat exchange device of the improved TOKAMAK test system according to claim 1 is characterized in that: A plurality of outer pin fins (42) are provided and are welded to the outer side of the inner cylinder (19) of the mixed water heat exchange tank in a multi-layer ring form, and two adjacent layers of pin fins (42) are arranged in a staggered manner.

7. The pre-mixed water heat exchange device of the improved TOKAMAK test system according to claim 1 is characterized in that: The invention also comprises a rotation speed sensing system, which comprises an oblate cylindrical NdFeB magnet (17), a rotation speed sensor (15), a Hall sensor probe (18) and a transmitter arranged in the rotation speed sensor (15), wherein the transmitter is located above the upper end cover (29), and the Hall sensor probe (18) of the rotation speed sensor (15) penetrates the upper end cover (29) and extends into the cavity of the inner tube (19) of the mixed water heat exchange tank; the oblate cylindrical NdFeB magnet (17) is embedded in the root of the fan-shaped rotating nozzle (16), and the center of the oblate cylindrical NdFeB magnet (17) and the probe (18) of the rotation speed sensor (15) are on the same vertical line.

8. The pre-mixed water heat exchange device of the improved TOKAMAK test system according to claim 1 is characterized in that: The mixed water heat exchange tank (5) is arranged horizontally, but is allowed to be tilted within a horizontal angle of ±15‰.

9. An improved TOKAMAK test system pre-mixed water heat exchange system, characterized in that: It includes a main cooling circuit, an ejection circuit and an auxiliary circuit; In the main cooling circuit, cooling water and chilled water are mixed in the water collector and distributor (3) and then enter the hollow cavity of the inner tube (19) of the mixing water heat exchange tank. The cooling water and chilled water are evenly sprinkled on the inner wall of the inner tube (19) of the mixing water heat exchange tank through the rotating nozzle (16) inside the cavity for mixing water heat exchange. The heat of the mixed fluid is transferred to the chilled water in the middle jacket (32) of the chilled water of the mixing water heat exchange tank, i.e., the chilled water of the ejection circuit, through the wall surface of the inclined wing (41) of the inner tube (19) of the mixing water heat exchange tank. The mixed fluid after being sprinkled enters the water collecting pool (40), and in the water collecting pool (40), it exchanges heat with the chilled water in the middle jacket (32) of the chilled water of the mixing water heat exchange tank again. Finally, it enters the water collecting pool (40) at the bottom of the inner tube (19) of the mixing water heat exchange tank, passes through the diverter cylinder (22), and enters the water tank (6) drop plate in the form of a triangular weir flow and flows into the water tank (6). When the main cooling circuit is in operation, the middle jacket (32) of the chilled water in the mixed water heat exchange tank in the ejection circuit is filled with chilled water, and the water flows from bottom to top; the outer jacket (33) of the cooling water in the mixed water heat exchange tank is filled with cooling water, and the water flows from top to bottom; In the ejection loop, the chilled water in the chilled water main pipe first passes through the chilled water jacket of the mixed water heat exchange tank and is then ejected to the jet pump (13); the unpowered jet pump (13) ejects the low-pressure chilled water at the end of the chilled water loop to the end of the high-pressure cooling water loop.

Images