• Proceedings of the Korean Radioactive Waste Society Conference
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• 2007.05a
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• pp.181-182
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• 2007

본 연구에서는 사용후핵연료봉으로부터 헐(Hull)과 펠릿(Pellet)을 분류하여 수납하는 용기에 관한 것이다. 수납용기는 분리된 헐과 펠릿을 함께 수납하되, 펠릿을 통과시키는 펠릿 통과부가 형성된 헐 수납용기와, 헐 수납용기 하부에 위치한 펠릿을 수납하는 수납용기를 구비하고, 펠릿 통과부를 선택적으로 개폐할 수 있는 헐 차단유닛 등이 있다. 따라서 유해지역인 핫셀(Hot-cell) 내에서 펠릿 조각이나 헐이 분산되는 위험을 피할 수 있어 안전성이 확보되고, 각각의 수납용기에 자동으로 분류 및 수납되는 공정을 도입하여 일괄적으로 작업을 진행시킬 수 있으며, 별도의 공정이 필요치 않아 작업시간을 절약할 수 있다.

• Journal of the Korean Society for Nondestructive Testing
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• v.30 no.4
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• pp.324-329
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• 2010

Fuel rods using in nuclear power plants consist of uranium dioxide pellets enclosed in zirconium alloy(zircaloy) tubes. It is vitally important for the pellet surface to remain free from pits, cracks and chipping defects after it is loaded into the tubes to prevent local hot spots during reactor operation. This paper investigates the feasibility study for detecting surface flaws of pellets contained within nuclear fuel rod through X-ray tomography simulation. Reconstructed images used by parallel and fan-beam filtered back projection method were presented and confirmed the accessibility between simulation data and MPS(missing pellet surface) image data.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05d
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• pp.306-311
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• 1996

CANFLEX 연료봉 다발을 구성하는 우라늄 펠릿이 장전된 핵연료봉의 공기중 진동특성을 진동 실험과 유한요소 해석을 통하여 구하였다. 유한요소 해석 시에는 우라늄 펠릿의 강성은 무시하고 질량은 지르칼로이 튜브에 부가하며, 연료봉 양단의 용접부위를 단순 지지보로 처리하는 모델을 제시하였다. 이 모델로부터 얻은 해석결과를 진동실험에서 구한 측정값과 비교하였다.

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.219.2-219.2
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• 2005

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.220.1-220.1
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• 2005

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.2
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• pp.157-166
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• 2014

A light water reactor (LWR) fuel rod consists of zirconium alloy cladding tube and uranium dioxide pellets with a slight gap between them. The modeling of heat transfer across the gap between fuel pellets and the protective cladding is essential to understanding fuel behavior under irradiated conditions. Many researchers have been developing fuel performance codes based on finite element method (FE) to calculate temperature, stress and strain for multidimensional analysis. The gap conductance model for multi-dimension is difficult issue in terms of convergence and nonlinearity because gap conductance is function of gap thickness which depends on mechanical analysis at each iteration step. In this paper, virtual link gap element (VLG) has been proposed to resolve convergence issue and nonlinear characteristic of multidimensional gap conductance. In terms of calculation accuracy and convergence efficiency, the proposed VLG model has been evaluated for variable cases.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1154-1157
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• 2003

The spent fuel slitting device is an equipment developed for the separation of the pellet and hull from the cutting fuel rod with length of 250 mm, and in order to feed UO$_2$ pellet. We have analyzed on the existing technologies for designing and producing of the slitting device in the first year(2001), based on these results, designed and produced the rod slitting device. It has effectively separated the pellet from the hull, but demanded the supplement separation work because of the mixing with pellet and hull in the vessel, and required the condition for the reducing time of the process. In the second year(2002), we have reduced the work time, performed the test and capacity evaluation with the improving device, based these results, and ensured the data demanded for designing of the spent fuel rod slitting device. We have compared with the DUPIC(Direct use of spent PWR fuel in CAND reactors) process, and developed the device for the purpose of reducing over 40 % in comparition with the DUPIC operation time(5 minutes). Based on these results, it will is effectively applied to available data for designing and producing of the hot test facility.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2011.10a
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• pp.161-162
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• 2011

유압동력사용 전제하에, 기계식탈피복을 고려하지 않을 때는 전단방식이 가장 유리함을 알 수 있다. 절단방식은 전단방식에 비해서 낮은 생산성이 단점이나, 높은 원형도의 연료봉 절단면이 요구되거나, 비산에 의한 칩 분리, 쿨링(cooling) 장치를 보완하면 절단방식이 유리하다. 또한 수평식 슬릿장치는 커팅 블레이드의 낮은 내구성으로 생산성이 낮은 것이 단점이나 내구성이 강한 공구를 사용하여 처리 속도를 향상한다는 전제에서 실험적 검증의 확보, 그리고 별도의 복잡한 펠릿/헐 분리장치를 보완하면 수평식 슬릿 방식이 유리하다.