A cooling circuit for a fusion reactor divertor

Abstract

The invention discloses a cooling circuit for a fusion reactor divertor, which includes a box body, an outer target plate, a dome, and an inner target plate. The inlet and outlet of the cooling circuit form a main cooling circuit with the box body; the coolant enters the box body from the inlet, first flows through the outer target plate, and then flows back to the box body, and the outer target plate is connected in series with the main cooling circuit; at the dome and the inner target plate, the coolant flowing out of the box body is divided into two branches, one flows to the dome, and the other flows to the inner target plate. The coolants of the two branches converge at the connection between the inner target plate and the box body, flow back to the box body and then to the outlet. The two branches are connected in parallel and then connected in series with the main cooling circuit; a "series-parallel-series" structure is formed from the inlet to the outlet. The invention distributes the flow through the outer target plate to the dome and the inner target plate while meeting the heat removal requirements of the divertor, which can effectively reduce the flow channel erosion caused by the excessively high flow rate of the inner target plate, and at the same time reduce the overall pressure drop of the cooling circuit, and has good comprehensive performance and fusion reactor application prospects.

Description

Technical Field

[0001] The invention relates to the technical field of divertor of a tokamak fusion device, and mainly to a cooling circuit of a fusion reactor divertor. Background Art

[0002] As one of the core internal components of the magnetic confinement tokamak fusion device, the divertor's main function is to remove the heat flow and particle flow from the core plasma to ensure the normal operation of the device. The divertor consists of an inner target plate, a dome, an outer target plate and a box body. The inner target plate, the dome and the outer target plate are composed of a plasma-facing unit and a transition support, which are called plasma-facing components. The box body, as the main load-bearing component, integrates the inner target plate, the dome and the outer target plate into a whole.

[0003] In the divertor structure design, the design of the cooling circuit is an issue that needs to be considered to realize the heat removal function of the divertor. At present, mature technologies, such as the cooling circuit of the ITER divertor, adopt a one-in-one-out series mode. The coolant enters the box body through the inlet, passes through the box body, flows through the outer target plate, the inner target plate and the dome in turn, and finally returns to the box body and flows out from the outlet. The EAST divertor directly adopts a similar series cooling method, that is, the inner target plate, the dome and the outer target plate are divided into two symmetrical parts. The coolant enters from one side and flows out from the other side, and a header box is used for transition in the middle. The design of these two cooling circuits has the advantages of simple structure and easy processing. However, for the future tokamak fusion reactor, it has obvious problems that need to be solved. The divertor is a fan-shaped structure. From the high field side to the low field side of the tokamak device, the annular width of the divertor gradually increases. With the increase of the large radius of the tokamak device, the width of the outer target plate of the divertor is much larger than the width of the inner target plate. The divertor adopts a one-in-one-out series cooling circuit. The flow rate at the inner target plate will be significantly higher than that at the outer target plate. The problems introduced are: 1) the pressure drop of the entire cooling circuit is too high, exceeding the design limit; 2) while maintaining the flow rate at the outer target plate, the excessively high flow rate of the inner target plate will increase the erosion of the inner wall of the pipeline. Summary of the invention

[0004] In order to solve the problems of too large difference in flow velocity between inner and outer target plates and too high pressure drop of cooling circuit in a one-in-one-out series cooling circuit mode of a divertor, the present invention proposes a cooling circuit of a fusion reactor divertor, which is a one-in-one-out "series-parallel-series" structure of a fusion reactor divertor cooling circuit mode, which makes full use of flow distribution, ensures that the flow velocity of the inner and outer target plates of the divertor meets the requirement of heat load removal, makes the flow velocity of the inner and outer target plates equivalent when using the same flow channel design, reduces the erosion of the pipeline caused by the excessively high flow velocity in the flow channel of the inner target plate; at the same time, the scheme can effectively reduce the pressure drop of the divertor cooling circuit.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A cooling circuit of a fusion reactor divertor, the fusion reactor divertor comprising an outer target plate, a dome, an inner target plate and a box body, the cooling circuit comprising an inlet and an outlet, the inlet, the outlet and the box body forming a main path of the cooling circuit;

[0007] The coolant enters the box body through the inlet, flows to the outer target plate through the cooling circuit main road, and forms branch road one; the coolant then flows back to the box body of the cooling circuit main road through the outlet of branch road one, and is divided into two branches at the position where the box body flows to the dome and the inner target plate, wherein the coolant in one branch flows to the dome, forming branch road two, and the coolant in the other branch flows to the inner target plate, forming branch road three; the coolant then flows back to the box body of the cooling circuit main road through the outlets of branch road two and branch road three, and reaches the outlet through the cooling circuit main road;

[0008] The branch one is connected in series with the cooling circuit main circuit; the branch two and the branch three are connected in parallel, and the formed parallel circuit is connected in series with the cooling circuit main circuit as a whole; the cooling circuit forms a "series-parallel-series" structure from the inlet to the outlet.

[0009] The beneficial effects of the present invention are:

[0010] The "series-parallel-series" structure of the divertor cooling circuit proposed in the present invention makes full use of the structural characteristics of the divertor in the form of a fan, divides the fan-shaped structure into three branches (corresponding to the inner target plate, the dome and the outer target plate) along the radial direction, introduces a structure in which the "inner branch" is connected in parallel with the "middle branch" and then connected in series with the "outer branch". Make full use of the flow distribution, ensure that the flow velocities of the inner and outer target plates of the divertor meet the requirements of heat load removal, make the flow velocities of the inner and outer target plates equivalent when using the same flow channel design, reduce the erosion of the pipeline caused by the excessive flow velocity in the flow channel of the inner target plate; at the same time, this scheme can effectively reduce the pressure drop of the divertor cooling circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 Schematic diagram of the divertor structure.

[0012] Figure 2 Schematic diagram of the divertor flow channel and coolant flow path.

[0013] Figure 3 Schematic diagram of the divertor cooling circuit of the present invention.

[0014] Description of the serial numbers in the accompanying drawings: 1-box body; 2-outer target plate; 201-outer target plate faces the plasma unit; 202-outer target plate transition support; 3-dome; 301-dome faces the plasma unit; 302-dome transition support; 4-inner target plate; 401-inner target plate faces the plasma unit; 402-inner target plate transition support. DETAILED DESCRIPTION

[0015] The specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings and examples. In the description of the present invention, it should be understood that the terms "inside", "middle", "outside", etc. used in the present invention indicate the orientation or position relationship based on the accompanying drawings, which is only for the convenience of simplifying the description of the present invention, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "branch one", "branch two", etc. are only used for description and cannot be understood as indicating or implying relative importance.

[0016] like Figure 1 As shown, the divertor of the fusion reactor is composed of a box body 1, an outer target plate 2, a dome 3 and an inner target plate 4. The box body 1 is used as the main bearing component, and the inner target plate 4, the dome 3 and the outer target plate 2 are integrated into a whole. The outer target plate 2, the dome 3 and the inner target plate 4 are collectively referred to as plasma-facing components. The outer target plate 2 is composed of an outer target plate facing plasma unit 201 and an outer target plate transition support 202; the dome 3 is composed of a dome facing plasma unit 301 and a dome transition support 302; the inner target plate is composed of an inner target plate facing plasma unit 401 and an inner target plate transition support 402.

[0017] like Figure 1 As shown, the outer target plate facing the plasma unit 201 and the outer target plate transition support 202 are fixed by pins, and the outer target plate transition support 202 and the box body 1 are connected by bolts; the dome facing the plasma unit 301 and the dome transition support 302 are fixed by pins, and the dome transition support 302 and the box body 1 are connected by bolts; the inner target plate facing the plasma unit 401 and the inner target plate transition support 402 are fixed by pins, and the inner target plate transition support 402 and the box body 1 are connected by bolts.

[0018] like Figure 2As shown, the coolant enters the box body 1 from the inlet; directly enters the outer target plate 2 at a position near the inlet in the box body 1, passes through the outer target plate transition support 202, the outer target plate faces the plasma unit 201, and then flows back to the box body 1; then flows to the left along the large radius direction of the tokamak device in the box body 1, and is divided into two branches at the box body position corresponding to the middle of the dome 3 and the inner target plate 4: one branch passes through the dome transition support 302, the dome faces the plasma unit 301, and then flows through the inner target plate transition support 402; the other branch flows through the inner target plate facing the plasma unit 401; the coolants of the two branches converge in the pipeline at the connection between the inner target plate 4 and the box body 1, and then flow back to the box body 1; finally, the coolant flows from left to right in the box body 1 to cool the box body 1, and then flows out from the outlet.

[0019] like Figure 3 As shown, the inlet, the box body 1 and the outlet constitute the main cooling circuit; the flow channel of the outer target plate facing the plasma unit 201 and the outer target plate transition support 202 constitutes branch one; the flow channel of the dome facing the plasma unit 301, the dome transition support 302 and the inner target plate transition support 402 constitutes branch two; the flow channel of the inner target plate facing the plasma unit 401 constitutes branch three. Branch one is connected in series with the main cooling circuit, and branch two and branch three are connected in parallel and then connected in series with the main cooling circuit, thereby forming a "series-parallel-series" cooling circuit mode. The flow rate of the main cooling circuit is determined according to the demand of the outer target plate to discharge the heat load, and then the flow rate flowing through the outer target plate is distributed to the inner target plate and the dome.

[0020] The working principle of the present invention is:

[0021] The divertor of the tokamak device is fan-shaped from the center of the device to the outside, and the annular width is wider as the distance from the center of the device increases. As the maximum radius of the tokamak device increases, the annular width difference between the inner and outer target plates of the divertor increases (the inner target plate is the component close to the center of the device). The flow direction of the coolant in the divertor is generally along the polar direction, and the flow through the outer target plate 2 is distributed to the inner target plate 4 and the dome 3 by forming a parallel branch between the inner target plate 4 and the dome 3 of the divertor.

[0022] The flow rate of the cooling circuit is determined by the flow rate requirement of the branch one of the outer target plate, so that the cooling performance at the outer target plate meets the heat removal requirement of the divertor; by reasonably designing the flow resistance of the branch two of the inner target plate and the branch three of the dome, when the branch one and the branch two are connected in series with the branch three parallel circuit, the flow rate of the inner target plate can be made equivalent to the flow rate of the outer target plate, thereby avoiding excessive flow rate of the inner target plate caused by direct series connection of the inner target plate and the outer target plate.

[0023] The divertor cooling circuit mode of the "series-parallel-series" structure can, on the one hand, effectively reduce the pressure drop of the inner target plate branch by reducing the flow velocity of the inner target plate (the pressure drop is positively correlated with the square of the flow velocity), and on the other hand, reduce the pressure drop of the entire circuit by reducing the flow path length of the cooling circuit that is completely connected in series (the pressure drop is positively correlated with the flow path length).

[0024] A fusion reactor divertor cooling circuit mode of the present invention distributes the flow through the outer target plate to the inner target plate and the dome through reasonable flow resistance design while ensuring that the flow velocity of the inner target plate facing the plasma unit is equivalent to that of the outer target plate (i.e., having the same heat load discharge capacity). The cooling circuit mode of the present invention can reduce pipeline erosion caused by excessive flow velocity in the flow channel of the inner target plate, and at the same time, the pressure drop of the entire circuit is low, and has good comprehensive performance and fusion reactor application prospects.

[0025] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. The described embodiments are only part of the embodiments of the present invention, not all of them. It should be pointed out that for those of ordinary skill in the art, without departing from the technical principles of the present invention, several improvements and substitutions can be made, and these improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A cooling circuit for a fusion reactor divertor, characterized in that: The fusion reactor divertor is composed of an outer target plate, a dome, an inner target plate and a box body, and the cooling circuit includes an inlet and an outlet, and the inlet, the outlet and the box body form a main path of the cooling circuit; The coolant enters the box body through the inlet, flows to the outer target plate through the cooling circuit main road, and forms branch road one; the coolant then flows back to the box body of the cooling circuit main road through the outlet of branch road one, and is divided into two branches at the position where the box body flows to the dome and the inner target plate, wherein the coolant in one branch flows to the dome, forming branch road two, and the coolant in the other branch flows to the inner target plate, forming branch road three; the coolant then flows back to the box body of the cooling circuit main road through the outlets of branch road two and branch road three, and reaches the outlet through the cooling circuit main road; The branch 1 is connected in series with the cooling circuit main circuit; the branch 2 and the branch 3 are connected in parallel, and the formed parallel circuit is connected in series with the cooling circuit main circuit as a whole; the cooling circuit forms a "series-parallel-series" structure from the inlet to the outlet; The outer target plate is composed of an outer target plate facing the plasma unit and an outer target plate transition support; the dome is composed of the dome facing the plasma unit and the dome transition support; the inner target plate is composed of the inner target plate facing the plasma unit and the inner target plate transition support; the inlet, the box body and the outlet constitute the main road of the cooling circuit; the flow channel of the outer target plate facing the plasma unit and the outer target plate transition support constitutes branch one; the flow channel of the dome facing the plasma unit, the dome transition support and the inner target plate transition support constitutes branch two; the flow channel of the inner target plate facing the plasma unit constitutes branch three; branch one is connected in series with the main road of the cooling circuit, branch two and branch three are connected in parallel and then connected in series with the main road of the cooling circuit, thereby forming a "series-parallel-series" cooling circuit mode.

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