JPH07306278A - Divertor structure - Google Patents

Abstract

PURPOSE:To shorten the distance between the inner wall of a vacuum vessel and the surface of a divertor structure facing the plasma while mountaining the cooling/heat removing capaciy by composing a forcibly cooling channel of a material having a high thermal conductivity on the side subjected to a heavy load and of a material having a high mechanical strength on he side fixed to a board. CONSTITUTION:A board 4 is joined to the inner wall 5 of a vacuum vessel at a fillet welded part 6 and a compositional member (stainless steel) 2 of forcibly cooling cannel is joined to the board 4. A compositional member (copper) 1 is joined metallurgically to the stainless steel 2 through a joining part 7 and a heat resistant material (armor member) 3 is joined to the copper 1. Consequently, the heat of plasma is transmitted from the armor member 3 to the cooling member efficiently through the copper 1 and a required heat removing performance is ensured. Furthermore, since the board 4 side is composed of the stainless steel 2 having a high mechanical strength, the divertor structure can be secured to the board 4 fixed to the inner wall 5 of vacuum vessel without requiring any additional material.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a diverter structure. More specifically, the present invention relates to a divertor structure arranged in the vacuum container of the tokamak-type fusion plasma experimental device facing the ultra-high temperature plasma. It can be applied to all other structures that are subjected to high heat load and require forced cooling for heat removal.

[0002]

2. Description of the Related Art An example of a conventional diverter structure is shown in FIG. This example uses a forced cooling channel 8 made of copper. As shown in the figure, the substrate 4 is joined to the inner wall 5 of the vacuum container, the metal fitting (substrate) 9 made of stainless steel is fixed to the substrate 4, and the metal fitting 9 is heat-resistant via the forced cooling channel 8. The material (armor material) 3 is bonded.

The heat-resistant material 3 faces the ultra-high temperature plasma in the vacuum vessel, and graphite or C / C composite (carbon fiber reinforced carbon composite material) which is a high melting point material is used. The forced cooling channel 8 is brazed to the heat resistant material 3 and is made of copper having high thermal conductivity. A coolant (not shown) flows in the hollow portion of the forced cooling channel 8 in order to cool and remove the heat-resistant armor material 3.

[0004]

In the tokamak fusion experimental apparatus, in order to obtain good plasma performance, the plasma facing surface of the divertor structure (the surface on the side subject to high heat load)
There is a strong demand for minimizing the distance between the inner wall 5 and the inner wall 5 of the vacuum container that fixes the diverter structure. However, in the conventional diverter structure, since the cross-sectional area of the forced cooling channel 8 is determined in order to secure the flow rate of the refrigerant, it is difficult to downsize the forced cooling channel 8 any further.

Further, the forced cooling channel 8 has relatively low mechanical strength because it uses copper or the like having high thermal conductivity, and in order to mechanically fix it to the inner wall 5 of the vacuum container, a comparison with stainless steel or the like is made. It was necessary to further bond to the substrates 4 and 9 composed of a material having high mechanical strength.

Therefore, there is a limit in reducing the distance between the plasma facing surface and the inner wall 5 of the vacuum container, and it has been strongly demanded to further reduce the distance. The present invention has been made in view of the above prior art, and provides a diverter structure capable of reducing the distance between the plasma facing surface of the diverter structure and the inner wall of the vacuum container while maintaining the cooling and heat removal capacity. With the goal.

[0007]

The structure of the present invention which achieves such an object is subjected to a high heat load, and in the diverter structure for removing the heat, the side of the forced cooling channel receiving the high heat load is made of a material having a high thermal conductivity. It is characterized in that the side of the forced cooling channel fixed to the substrate is made of a material having high mechanical strength, and the materials are metallurgically bonded. Further, it is characterized in that copper is used as the material having high thermal conductivity and stainless steel is used as the material having high mechanical strength.

[0008]

Since the forced cooling channel on the side that receives a high heat load, that is, the side that comes into contact with the armor material that is made of a heat-resistant material is made of a material with high thermal conductivity, the amount of heat that the armor material receives from the plasma is It is efficiently transmitted to the coolant. The side of the substrate that constitutes the forced cooling channel, that is, the side that is mechanically fixed to the substrate on the side opposite to the side that receives a high heat load, is made of a material with high mechanical strength, and therefore other additives are not interposed. Instead, it can be fixed to the substrate fixed to the inner wall of the vacuum container.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the embodiments shown in the drawings. FIG. 1 shows an embodiment of the present invention. In this embodiment, the forced cooling channel 8 is composed of two constituent materials (Cu) 1 and two constituent materials (stainless steel) 2.

As shown in the figure, the substrate 4 is joined to the inner wall 5 of the vacuum vessel at the fillet weld 6 and the substrate 4 is joined.
Stainless steel that forms part of the forced cooling channel on the
Copper 1 forming a part of the forced cooling channel is metallurgically bonded to the stainless steel 2 through a bonding portion 7, and a heat resistant material (armor material) 3 is bonded to the copper 1. There is.

The copper 1 and the stainless steel 2 each have a U-shaped cross section, and a hollow portion is formed in the forced cooling channel connecting them. A refrigerant (not shown) flows in the hollow portion to remove heat and cool the heat resistant material. The copper 1 and the stainless steel 2 are melt-welded at the joint 7, and in this embodiment, they are metallurgically joined by EBW.

In the diverter structure of this embodiment having the above-mentioned structure, the forced cooling channel on the side that receives a high heat load, that is, the side that contacts the armor material made of a heat-resistant material, is made of copper 1 which is a material having high thermal conductivity. Therefore, the amount of heat received by the armor member 3 from the plasma is efficiently transferred to the coolant, and the necessary heat removal performance can be secured. In addition, the side of the substrate that constitutes the forced cooling channel, that is, the side that is mechanically fixed to the substrate on the side opposite to the side that receives a high heat load, is made of stainless steel 2 that is a material with high mechanical strength. , And can be fixed to the substrate 4 fixed to the inner wall 5 of the vacuum container without interposing other additives (the conventional substrate 9).

Another embodiment of the present invention will be described with reference to FIG. This embodiment shows a modification of the above-mentioned embodiment. That is, the substrate 4 is joined to the inner wall 5 of the vacuum container at the fillet welded portion 6 and the stainless steel 2 forming a part of the forced cooling channel is joined to the substrate 4, and the forced cooling channel is connected to the stainless steel 2. 1 is partially metallurgically bonded to each other via a bonding portion 7, and a heat resistant material (armor material) 3 is bonded to the copper 1. The copper 1 and the stainless steel 2 are brazed and welded at the joint 7.

Copper 1 is plate-shaped, and stainless steel 2
Has a U-shaped cross section, and a hollow portion is formed in the forced cooling channel connecting them. A refrigerant (not shown) flows in the hollow portion to remove heat and cool the heat resistant material.

Also in the diverter structure of the present embodiment having the above-mentioned structure, as in the above-mentioned embodiments, the side of the forced cooling channel which receives a high heat load is made of copper 1 which is a material having high thermal conductivity and the forced cooling is carried out. Since the side of the channel fixed to the substrate is made of stainless steel 2 which is a material having high mechanical strength, and the copper 1 and the stainless steel 2 are metallurgically bonded at the joint 7, the cooling removal is performed. It is possible to reduce the distance between the plasma facing surface of the diverter structure and the inner wall of the vacuum container while maintaining the heat capacity.

[0016]

As described above in detail with reference to the embodiments, in the present invention, the forced cooling channel is constructed by combining two kinds of materials having different characteristics. While maintaining the above, the distance between the plasma facing surface of the diverter structure and the inner wall of the vacuum container can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of a diverter structure according to an embodiment of the present invention.

FIG. 2 is a sectional view of a diverter structure according to another embodiment of the present invention.

FIG. 3 is a cross-sectional view of a conventional diverter structure.

[Explanation of symbols]

 1 constituent material (Cu) 2 constituent material (stainless steel) 3 armor material 4 substrate 5 inner wall of vacuum vessel 6 fillet weld 7 joint 8 forced cooling channel 9 substrate

Claims (3)

[Claims] 1. In a diverter structure that receives a high heat load and removes the heat, the side of the forced cooling channel that receives the high heat load is made of a material with high thermal conductivity, and the side of the forced cooling channel that is fixed to the substrate is fixed. A diverter structure comprising a material having high mechanical strength, and the materials being metallurgically bonded. 2. The diverter structure according to claim 1, wherein copper is used as the material having high thermal conductivity. 3. The diverter structure according to claim 1, wherein stainless steel is used as the material having high mechanical strength.