JPS5810688A - Interstructure of tank type reactor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a bulkhead structure of a reactor vessel of a tank-type fast breeder reactor, and more particularly, to a shape of the bulkhead structure with low heat transfer and low thermal stress.

As shown in the schematic diagram of the reactor internal structure in Figure 1, the conventional bulkhead structure is a thin plate that connects the outer periphery of the core structure and the inner periphery of the main vessel.
It has a structure divided by boards.

The partition wall structure (hereinafter referred to as the partition plate) serves to separate the high temperature sodium heated in the reactor core and the low temperature sodium heat exchanged in the intermediate heat exchanger, and a large temperature difference occurs between the top and bottom surfaces of the partition plate. From the viewpoint of thermal efficiency, it is desirable that the temperature difference between the high-temperature sodium and the low-temperature sodium be as large as possible. For this purpose, it is necessary to make the partition plate thicker, but if it is made thicker, there is a risk that the partition plate will be damaged due to the large thermal stress. Therefore, conventional partition plates are made of laminated thin plates,
Alternatively, a two-layer structure filled with sodium is used, but the former has a large weight.
The latter has the risk of buckling due to thermal stress generated from the temperature difference between the upper and lower plates.

The object of the present invention is to have a lightweight structure that is less likely to buckle due to thermal stress.
The aim is to provide a bulkhead structure with a low heat transfer coefficient.

In order to make the partition wall structure lightweight, it is necessary to use thin partition plates. In the present invention, the partition plate is made of a single thin plate, and in order to prevent heat transfer due to sodium convection near the partition plate, the extremely thin plate is divided and fixed at a constant interval parallel to the partition plate. This is what I did. (Hereinafter, this will be referred to as a baffle plate.) By providing this baffle plate, the temperature gradient in the thickness direction of the partition plate can be significantly reduced. Also, since the baffle plate is divided, thermal buckling will not occur.

An embodiment of the present invention will be explained with reference to FIG. Partition wall structure 8
The partition plate 9, which is the main structural element of the vessel, is fixed to the outer periphery of the core structure 4 and the inner periphery of the main passenger unit 2, and separates the high-temperature sodium located in the upper part of the vessel and the low-temperature sodium located in the lower part. and are separated.

A baffle plate 10.11 made of a small piece of thin plate is fixed to the partition plate via a thin support 12 in parallel with the partition plate. The baffle plates are arranged at a small interval from each other. Now, if the temperature of the high temperature sodium at the top is Th1, the low temperature at the bottom, and the temperature of thorium is Tt, then the temperature difference between the upper and lower baffle plates 10 and 11 is is Th-Tt, and if the distance between the baffle plates is L, the temperature gradient of the partition plate (thickness is t) is approximately (Th-Tt>/L+t).On the other hand, when there is no baffle plate, Th and Tt directly on the partition plate.
The temperature gradient of the partition plate is (Th-
Tt)/l.

Therefore, the ratio of the temperature gradient between the present invention with a baffle plate and the case without a baffle plate is t/L+t, and generally L>
>t, so t/L+t((1) can significantly reduce the temperature gradient.

FIG. 3 shows a baffle plate 10' in another embodiment of the invention.

11 are superimposed on each other. This further prevents heat transfer due to convection between the sodium in the shijiya cutting board and the sodium in the jamblin row, and the temperature gradient of the partition plate can be further reduced.

According to the present invention, since the partition plate can be made of a thin plate, it is possible to make a partition wall structure that is lightweight, has low heat transfer, and is resistant to buckling.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view showing the equipment structure of a tank-type fast breeder reactor, FIG. 2 is a partial perspective view showing an embodiment of the present invention, and FIG. 3 is a sectional view showing another embodiment of the present invention. . l... Roof slab, 2... Main vessel, 3... Concrete wall, 4... Core structure, 5... Core support structure, 6... Sodium pump, 7... Intermediate Heat exchanger, partition wall structure, 9... partition plate, 10.11.
... Baffle board, 12... Support. Agent Patent Attorney Akio Takahashi

Claims (1)

[Claims] 1. In a partition plate that separates high silver sodium and low temperature sodium in the reactor vessel of a tank-type fast breeder reactor in which an intermediate heat exchanger, a sodium pump, and a reactor core structure are placed in the same vessel, the partition plate is placed away from the partition plate. A bulkhead structure for a tank-type furnace characterized by fixing a plurality of thin plates (called baffles) located parallel to the .