JPH0746149B2 - Breeder temperature control method for fusion reactor breeding bracket - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for controlling a breeder material temperature of a blanket for breeding of a fusion reactor, and more specifically, a thermal resistance material filled around a cooling pipe of the breeder blanket for fusion. This is a temperature control method that adjusts according to changes in the output of the furnace.

[Prior Art] The fusion reactor 1 converts the fusion energy generated by the plasma 2 shown in FIG. 1 into thermal energy by the breeding blanket 3 installed around the plasma 2 and removes it to perform fusion fuel. To produce tritium.

FIG. 2 is a partial cross-sectional perspective view for explaining the structure of the breeding blanket 3, in which a cooling pipe 7 is arranged in a blanket container 6 formed by combining an outer wall 4, a shell conductor 5 and the like, and the cooling is performed. Around the tube 7, a lithium compound molded into small spheres (eg lithium oxide, lithium aluminum oxide)
The breeding material 8 such as

As shown in FIG. 3, a spacer 9 is concentrically arranged around the cooling pipe 7, and a helium gas for controlling the temperature of the breeding material 8 is provided in the space between the spacer 9 and the cooling pipe 7. A thermal resistance material such as is filled in to form the thermal resistance layer 10.

The fusion energy generated in the plasma 2 in this way produces tritium in the breeding material 8, and this tritium is recovered by the helium purge gas flowing in the breeding material, and at the same time, the helium gas flowing in the cooling pipe 7 or It is extracted as thermal energy by a coolant such as water.

[Problems to be Solved by the Invention] By the way, in the tritium breeding blanket 3 having a solid lithium compound or the like as the breeding material 8, the thermal energy removed from the cooling pipe 7 changes due to a change in output. The temperature of the breeding material 8 changes in accordance with this change. In this case, when the breeding material 8 becomes high in temperature, thermal stress cracking occurs and a small amount of water in the breeding blanket 3 reacts with the breeding material 8 to cause the breeding material 8 to react. Problems such as mass transfer occur. Further, when the breeding material 8 has a low temperature, tritium is occluded by the breeding material 8 and a problem occurs in the tritium inventory. Therefore, in order to continuously collect the generated tritium while maintaining the soundness of the breeding material 8, it is necessary to control the breeding material 8 to maintain a constant temperature range, for example, 400 ° C to 1000 ° C in lithium oxide. There is.

In order to control the minimum temperature of the breeding material 8, a thermal resistance layer 10 composed of stationary helium gas is provided between the breeding material 8 and the cooling pipe 7, and the width of the helium gap around the cooling pipe 7 is provided. The method of adjusting such as the time of production according to the nuclear heating rate is taken. However, with these methods, it is difficult to accurately control the minimum temperature of the breeding material 8 at a position close to the thermal resistance layer in response to changes in output and variations in the breeding material heat rate, and the width of the helium gap can be changed at any time. There has been a problem that a complicated control mechanism is required to freely adjust.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a breeder blanket temperature control method for a breeder blanket capable of coping with output changes of a fusion reactor.

[Means for Solving the Problems] The above object is achieved by the method for controlling the breeding material temperature of the fusion reactor breeding blanket described in the claims. That is, (1) the cooling pipe arranged in the tritium breeding blanket of the fusion reactor has a double pipe structure, the coolant is circulated in the inner pipe of the double pipe, and the inner pipe and the outer pipe of the double pipe are In a fusion reactor breeding blanket having a structure in which a heat resistance material is circulated in the gap between the tube and a heat resistance layer, the composition ratio of the heat resistance material is adjusted by adjusting the component ratio of the heat resistance material according to the output of the fusion reactor. Temperature control method for breeder temperature of fusion reactor breeder blanket.

(2) The cooling pipe arranged in the tritium breeding blanket of the fusion reactor has a double pipe structure, and the coolant is circulated in the inner pipe of the double pipe to form the inner pipe and the outer pipe of the double pipe. In a fusion reactor breeding blanket having a structure in which a thermal resistance material is circulated in the gap part of the reactor to form a thermal resistance layer, depending on the output of the fusion reactor, the thermal resistance material is A breeding material temperature control method for a fusion reactor breeding blanket, wherein the breeding material temperature is controlled by selecting one of two states.

(3) The cooling pipe arranged in the tritium breeding blanket of the fusion reactor has a double pipe structure, and the coolant is circulated in the inner pipe of the double pipe to form the inner pipe and the outer pipe of the double pipe. In the fusion reactor breeding blanket having a structure in which the thermal resistance material is circulated in the gap of the thermal resistance layer, the composition ratio of the thermal resistance material is adjusted according to the output of the fusion reactor, and the adjusted thermal resistance material is A breeding material temperature control method for a fusion reactor breeding blanket, wherein the breeding material temperature is controlled by selecting one of two states, a static state and a laminar flow state, in the thermal resistance layer.

Is.

[Operation] As described above, the cooling pipe has a double pipe structure, and the heat resistance material gas is circulated between the outer pipe and the inner pipe of the double pipe to form the heat resistance layer. In other words, the gases having different thermal resistance values can be used individually or mixed in different ratios to change the thermal resistance value of the thermal resistance material gas itself, and to change the state of the thermal resistance material gas in the thermal resistance layer. The thermal resistance value of the gas is changed by selecting one of the two states, the stationary state and the laminar flow state, and the thermal resistance value change based on the change of the component of the thermal resistance material gas and the heat based on the state change of the gas. By changing either or both of the changes in resistance value, the breeding material is kept within a constant temperature range.

[Examples] Specific examples in which a mixed gas of helium gas and argon gas is used as the heat resistance material will be described below.

FIG. 4 is a graph showing the rate of change of the thermal resistance value when helium gas (hereinafter referred to as He) and argon gas (hereinafter referred to as Ar) are mixed and used as the thermal resistance material having different thermal resistance values, The horizontal axis is a scale showing the volume fraction of He and Ar, where 0 is 0% He, 100% Ar, and 100 is 100 He.
%, Ar represents 0%. The vertical axis uses the ratio of the thermal resistance values of the mixed gas as a scale.

Curve A shows the state of change in the thermal resistance value of the mixed gas in the stationary state when the thermal resistance value of He100% in the stationary state is 1, and the value is about 8.2 at 100% Ar. The thermal resistance value changes as shown by the curve A according to the mixing ratio of He, Ar and He.

A curve B represents the state of change in the thermal resistance value of the mixed gas in the laminar flow state. If the gas in each of the mixed states is in the laminar flow state, the thermal resistance value is Also shows that it will decrease to about 0.75.

A first invention of the present application is a heat resistance layer around a cooling pipe 7 arranged in a breeding blanket 3 shown in FIGS. 2 and 3.
A plurality of gases having different heat resistance values such as He or Ar are used as the heat resistance material to be filled in 10, and a specific gas is selected or mixed from the plurality of gases according to the output of the fusion reactor. By adjusting a gas having a required thermal resistance value, the thermal resistance layer 10 is filled with the gas. As shown in FIG. 4, depending on the type or mixing ratio of the gas, for example, the thermal resistance values of He and Ar are greatly different in the range of about 8.2 times as described above, and furthermore, they continuously change. The temperature of the outer surface of the thermal resistance layer 10 can be controlled within a wide range by adjusting the component ratio of, and based on this, the breeding material in the fusion reactor breeding blanket is higher than the minimum temperature required by the breeding material. By contacting the outer surface of the thermal resistance layer 10 controlled to a high temperature, the required minimum temperature can be reliably maintained.

A second invention of the present application is a heat resistance layer around a cooling pipe 7 arranged in the breeding blanket 3 shown in FIGS. 2 and 3.
A gas such as He or Ar is circulated as a heat resistance material in 10 and the gas is kept stationary in the heat resistance layer according to the output of the fusion reactor or the gas is continuously supplied. By selecting either the laminar flow state, the thermal resistance value of the gas as the thermal resistance material is changed, and thereby the temperature of the outer surface of the thermal resistance layer is raised to the minimum temperature required by the breeding material or higher. By holding it, it is possible to secure the minimum temperature of the breeding material in the fusion reactor breeding blanket.

By keeping the gas as the heat resistance material in the heat resistance layer 10 in the laminar flow state, the heat resistance value of the gas can be lowered to 0.75 in the static state as shown in FIG. It is possible to respond to changes in output and the like extremely quickly and effectively.

A third invention of the present application uses a plurality of gases having different thermal resistance values such as He or Ar as a thermal resistance material, and selects a specific gas from the plurality of gases according to the output of the fusion reactor or the like. Alternatively, a gas having a required heat resistance value is prepared by mixing, and the gas is circulated in the heat resistance layer 10 around the cooling pipe 7 arranged in the breeding blanket 3 shown in FIG. 2 and FIG. It is possible to select either the stationary state or the laminar flow state of the heat resistant material in the heat resistant layer.

When He and Ar are used as the thermal resistance material, the thermal resistance value of the thermal resistance material can be changed up to about 8.2 times by changing the mixing ratio as shown in Fig. 4. In addition to being able to sufficiently cope with the case where a large change in the heat resistance material is expected, when the relatively small output change occurs during the operation of the fusion reactor, the state of the thermal resistance material can 75 by selecting either of the flow conditions
%, It becomes possible to maintain the breeding material temperature at a necessary and minimum temperature accurately and quickly.

If the mixed gas is continuously supplied and the laminar flow state is maintained while adjusting the mixing ratio of He and Ar, the ratio of the thermal resistance values is continuously between 0.75 and 6 as shown by the curve B in FIG. And the minimum temperature of the breeding material 8 can be controlled. At this time, the rate of change in the thermal resistance value becomes slower when the mixed gas is kept in the laminar flow state than in the static state.
Temperature control becomes easy.

In this way, the thermal resistance value is changed while adjusting the mixing ratio of He and Ar in the thermal resistance layer 10, and the flow state of the mixed gas is changed by allowing the mixed gas to stand still and allowing it to flow in a laminar flow. By doing so, the thermal resistance value can be changed between the curves A and B, and the range of change of the thermal resistance value in this case is 0.75 to 8.2 in FIG.
Therefore, the ratio of the maximum power density to the minimum power density is 10 or more, and the temperature of the breeding material 8 can be controlled in a wider range.

As a method of detecting the temperature of the breeding material 8 in the first invention, the second invention and the third invention of the present application, a temperature detecting means for the breeding material 8 is attached to the spacer 9 arranged around the cooling pipe 7. You may

[Advantages of the Invention] As described above, the component ratio of the thermal resistance material is adjusted, the flow state is adjusted to change the thermal resistance value, or at the same time, these are adjusted to change the thermal resistance value. The simple method of dealing with changes in the output of the fusion reactor and fluctuations in the heat generation rate of the breeding material keeps the temperature within the constant temperature range required for continuous recovery of the tritium that has produced the breeding material. Since it can be changed, controllability is improved, and excellent temperature control can be performed in a wide range.

[Brief description of drawings]

1 is a schematic sectional view for explaining the operation of the fusion reactor, FIG. 2 is a partial sectional perspective view for explaining the structure of the breeding blanket, FIG. 3 is a detailed perspective view of a cooling pipe, and FIG. 4 is 7 is a graph showing changes in thermal resistance of He-Ar mixed gas. 1 ... Fusion reactor, 2 ... Plasma, 3 ... Breeding blanket, 7 ... Cooling tube, 8 ... Breeding material, 9 ... Spacer,
10 ... Thermal resistance layer, A ... Thermal resistance value curve when the He-Ar mixed gas is kept stationary, B ... Thermal resistance value curve when the He-Ar mixed gas is kept laminar.

Continuation of the front page (56) Reference JP-A-60-79287 (JP, A) JP-A-60-93374 (JP, A)

Claims (3)

[Claims] 1. A cooling pipe arranged in a tritium breeding blanket of a fusion reactor has a double pipe structure, a coolant is circulated in the inner pipe of the double pipe, and the inner pipe and the outer pipe of the double pipe are provided. In a fusion reactor breeding blanket having a structure in which a heat resistance material is circulated in the gap between the tube and a heat resistance layer, the composition ratio of the heat resistance material is adjusted by adjusting the component ratio of the heat resistance material according to the output of the fusion reactor. A method for controlling a breeding material temperature of a fusion reactor breeding blanket, which comprises controlling the temperature. 2. A cooling pipe arranged in a tritium breeding blanket of a fusion reactor has a double pipe structure, a coolant is circulated in the inner pipe of the double pipe, and the inner pipe and the outer pipe of the double pipe are provided. In a fusion reactor breeding blanket having a structure in which a thermal resistance material is circulated in the gap between the tube and the thermal resistance layer, the thermal resistance material is placed in a stationary state and a laminar flow in the thermal resistance layer according to the output of the fusion reactor. State 2
A breeding material temperature control method for a fusion reactor breeding blanket, which comprises controlling the temperature of the breeding material by selecting one of two states. 3. A cooling pipe disposed in a tritium breeding blanket of a fusion reactor has a double pipe structure, a coolant is circulated in the inner pipe of the double pipe, and the inner pipe and the outer pipe of the double pipe are provided. In a fusion reactor breeding blanket with a structure in which a thermal resistance material is circulated in the gap between the tube and a thermal resistance layer, the component ratio of the thermal resistance material is adjusted according to the output of the fusion reactor, and the adjusted thermal resistance is adjusted. A breeding material temperature control method for a fusion reactor breeding blanket, characterized in that the temperature of the breeding material is controlled by selecting one of two states, a static state and a laminar flow state, in the thermal resistance layer.