• The KSFM Journal of Fluid Machinery
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• v.10 no.2 s.41
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• pp.41-45
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• 2007

The shutoff unit was designed to provide rapid insertion of neutron absorbing material into the reactor core to shutdown the reactor quickly and also to withdraw the absorber slowly to avoid a log-rate trip. Four shutoff units were installed on the HANARO reactor but the half-core test facility was equipped with one shutoff unit. The reactor trip or shutdown is accomplished by four shutoff units by insertion of the shutoff rods. The shutoff rod(SOR) is actuated by a directly linked hydraulic cylinder on the reactor chimney, which is pressurized by a hydraulic pump. The rod is released to drop by gravity, when triplicate solenoid valves are de-energized to vent the cylinder. The hydraulic pump, pipe and air supply system are provided to be similar with the HANARO reactor. The shutoff rod drops for 647mm stroke within 1.13 seconds to shut down the reactor and it is slowly inserted to the full down position, 700mm, with a damping. We have conducted the drop test of the shutoff rod in order to show the performance and the structural integrity of operating system of the shutoff unit. The present paper deals with the 647mm drop time and the withdrawal time according to variation of the pool water temperature, the water level and the core flow.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.10a
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• pp.55-60
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• 1995

CANDU형 원자로의 노심해석을 위해 핵연료 격자 및 반응도 설비(reactivity devices)에 대한 2군 군정수가 필요하다. 특히 CANDU형 원자로의 노심해석에 있어서 반응도 설비나 구조물은 증분격자 상수(Incremental Cross Section)에 의해 묘사된다. 현재 CANDU형 원자로의 반응도 설비의 증분격자 상수를 계산하기 위해 MULTICELL 코드를 사용하여 계산하고 있다. 그러나 weak absorber에 대해 기존의 증분격자 상수를 이용하여 계산한 반응도가는 시운전(Phase-B)조건에서의 노물리 시험치보다 다소 과소평가하고 있다. 본 연구에서는 증분격자 상수 계산 방법의 개선 방향을 모색하기 위해 SHETAN 및 MCNP 코드로 단일 격자에서의 반응도가를 계산하여 비교, 평가하였다. HCNP 계산의 결과는 조정봉(Adjuster rods)과 흡수봉/정지봉 (Mechanical Control Absorber/Shutoff rod)은 MULTICELL의 계산 결과보다 적으며, 경수영역 조절기(Liquid Zone Controller)는 크게 나타났다. 또한 SHETAN 코드를 이용한 결과는 MULTICELL의 결과보다 약간 크게 나타났다.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.4 no.2
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• pp.57-61
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• 2008

During the period of retubing work for the licensing renewal, the fuel channels, calandria tubes and feeders of CANDU Reactors will be replaced, and calandria visual examination will be performed. This period is a unique opportunity to inspect the inside of the calandria. The visual inspection for the calandria vessel and its internals of Wolsong NPP is scheduled for confirming the calandria integrity. The first visual inspection for the calandria is planned in Pt. Lepreau led by AECL. The visual inspection for Wolsong NPP, led by NETEC(Nuclear Engineering & Technology Institute) of KHNP, will employ 3D laser scanner and 3D CAD Mock-up for the first time in the world, in addition to a conventional video camera. The inspection system is composed of a robot with the 3D laser scanner, a video camera and a hardness meter.