Proposal of safety demonstration test plan of HTTR by cold test of loss of forced cooling with vessel cooling system inactive

Takada, Shoji; Shinohara, Masanori ; Seki, Tomokazu; Shimazaki, Yosuke ; Ono, Masato ; Tochio, Daisuke ; Iigaki, Kazuhiko ; Sawa, Kazuhiro

The loss of forced cooling with vessel cooling system inactive has been planned by using HTTR at the reactor power 9 MW. In this test, the forced cooling of reactor core is lost and the vessel cooling system which removes decay heat from core is tripped. In the test, the technical items such that the temperature of water cooling tubes is expected to be higher are considered. The methods to solve such technical items were proposed. The proposed methods were verified based on the test data of the cold test toward the proposal of test plan of safety demonstration test. In the cold test, the two water trains of vessel cooling system was tripped under the condition that the reactor was heated up without nuclear heating. The reactor inlet temperature was set at 120 and 150C.