Design of the dual instrumented fuel rods to measure the nuclear fuel characteristics during Irradiation test at HANARO

The instrumented capsule for the nuclear fuel irradiation test (hereinafter referred to instrumented fuel capsule), which are crucial for the verification of a nuclear fuel performance and safety, have been developed at HANARO(High-flux Advanced Neutron Application Reactor). The irradiation test of the first instrumented fuel capsule(02F-11K) was carried out in March 2003 for 1,296 MWD(Mega Watt Day) and the irradiation test of the second instrumented fuel capsule(03F-05K) was carried out in April 2004 for 1,533MWD at HANARO. Through the irradiation tests of the two capsules, the design specifications and safety of the instrumented fuel capsule were verified successfully. In the 02F-11K instrumented fuel capsule, only the technologies for measuring the center temperature of the nuclear fuel and neutron flux were implemented. In the 03F-05K instrumented fuel capsule, the technologies for measuring the center temperature of the nuclear fuel, the internal pressure of the fuel rod, the elongation of the nuclear fuel and the neutron flux were implemented. The purpose of this paper is to develop the dual instrumented technology that enables two characteristics to be measured simultaneously in one fuel rod. Therefore, this paper presents the design of the dual instrumented fuel rods and the plan of the irradiation test for the newly designed fuel rods