A method for maintaining the temperature of a sample to be irradiated set at an irradiation device using radiation in a nuclear reactor at a target temperature

摘要

PURPOSE:To maintain a specimen at required irradiation temperature by using a partition plate for making recovering flow as a heating body. CONSTITUTION:After in an irradiation device feed water which is fed in a feed water feed tube 1 is flowed down between the outer wall and a partition plate 2 of the device and passed in the lower end of the partition plate 2 of the device lower part, the feed water is caused to ascend in the device. When the feed water is turned to ascending flow, it is put into contact with an irradiation specimen supporter 3 and an irradiation specimen 4. The thickness of the partition plate 2 is made thicker than conventional thickness. Thus, since the partition plate is heated by gamma rays to become a heating body, contributes to the heating of the feed water flowing at the outside thereof, further, heat flow of the inside to the outside is lowered and temperature lowering of the feed water can be reduced, the specimen can be heated and held at the prescribed temperature.