Reflector-controlled fast reactor and its neutron reflector

摘要

PPROBLEM TO BE SOLVED: To reduce a time variation in reactivity of a fast reactor of reflector control type without depending on the control of elevation speed of the reflector and the control of supply water flow rate. PSOLUTION: The reflector control type fast reactor controlling a reactivity of a core 2 by moving up and down the neutron reflectors 25 and 26 placed outside the core 2 submerged in liquid metal coolant and controlling a leak of neutrons out of the core 2. The neutron reflectors 25 and 26 should be gradually moved upward so as to match a reactivity variation by fuel burning, and at least a part of the lower region 26 of the neutron reflector is a high reflection region with higher reflection capability of fast neutron than another region 25. The higher reflection region 26 is in the range of 1/4 to 1/2 from the lower end of the neutron reflector. PCOPYRIGHT: (C)2005,JPO&NCIPI