| 摘要 |
PROBLEM TO BE SOLVED: To make appropriate the coefficient of pressure loss in a channel at an entrance orifice etc., arranged at a part surrounded by reinforcing beam plates, to highly accurately uniformize the quantity of flow in fuel assemblies, and thus to improve the cooling performance. SOLUTION: A reactor core support plate 6; a reinforcing beam 7 for reinforcing the reactor core support plate 6 from the side of its lower surface; a plurality of control rod guide tubes 10, which are vertically raised from the bottom side of the nuclear reactor pressure container and of which the upper ends are each combined with the sections of fuel support holes of the reactor core support plate 6; a fuel-support metal fixture 16, which is inserted in the upper end of each control rod guide tube and which supports the lower ends of the plurality of fuel assemblies 15, supported by the reactor core support plate 6 and arranged vertically in a reactor core; and an entrance orifice 19, provided at the fuel support metal fixture 16 for controlling the quantity of flow of a coolant flowing to the fuel assemblies 15. A vortex control means controls the vortexes of the coolant flowing into the entrance orifice 19, provided at the fuel support metal fixture 16 and is provided on the downstream side of the entrance orifice 19. COPYRIGHT: (C)2004,JPO
|
