http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
STAR-CCM+를 활용한 DEFCON-S 실험의 파편층 형성 시뮬레이션
엄정현,나인식,탁기영,정해용 한국유체기계학회 2023 한국유체기계학회 논문집 Vol.26 No.6
In a severe accident in a light-water reactor, molten corium can be formed and discharged into the reactor cavity. Assuming complete fragmentation of the ex-vessel corium by FCI, the DEFCON-S experiment, which was conducted to evaluate the formation and coolability of the debris bed using particles, was simulated by CFD. In this study, a mesh sensitivity analysis was performed beforehand to select the mesh size for the CFD simulation of the DEFCON-S experiment. For CFD analysis involving DEM models, it is necessary to select a mesh that adequately resolves both the fluid domain and the DEM particles. In addition, to validate the selected mesh size and simulate the DEFCON-S experiment, the analysis was performed under the same conditions as the experiment, and the analysis results were compared and evaluated with the actual experimental results. The deviation between the simulation and experimental results for the diameter and height of the particle bed in CFD is 4.6% and 3.8%. The shape and size of the generated particle bed closely match the experimental results as well.
엄정현,박현희,서동선,허웅,김준범,김용곤,Eom, Jung-Hyun,Park, Hyun-Hee,Seo, Dong-Sun,Huh, Woong,Kim, Joon-Bum,Kim, Yon-Gon 한국전기전자학회 1998 전기전자학회논문지 Vol.2 No.1
고속도로 등의 대형 구조물의 표면 요철을 측정하기 위한 높은 반복율의 광학적 근 거리 측정기를 개발하였다. 삼각 측정법의 원리에 의한 거리 계측을 위해, 광원으로는 발광 다이오드를 사용하였으며 물체에서 반사된 광의 각도 검출기로는 1차원 위치 감응 광 검출기를 사용하였다. 개발된 거리 측정기는 물체의 반사율 변화를 극복하기 위한 자동 전력 조절 기능과 일정한 배경 광잡음은 물론 시간에 대해 변하는 배경 광잡음까지도 제거할 수 있는 전기적 배경잡음 제거기능을 갖고 있다. 거리 측정기의 장착 및 요철의 깊이를 고려하여 설정된 $22{\sim}38cm$의 측정거리에 대한 실험결과, 물체의 반사율에 관계없이 ${\pm}1.5mm$ 이내의 측정오차를 보였다. We develope a high repetition rate, short distance, optical range finder for surface roughness measurements of large structures, such as a highway road, etc. For range measurement based on a triangulation principle, we use a light emitting diode and an one dimensional Position sensitive photodetector for a light source and an angle detector of the reflected light at the object, respectively. The range finder has automatic power control and electrical background noise rejection capabilities which enable it to overcome variations of an object reflectance and to eliminate time-varying, as well as constant, background light noises. Our experimental results show less than ${\pm}1.5mm$ of measurement errors regardless of an object reflectance, for $22{\sim}38cm$ object ranges which are determined by considering the installation of the range finder and the depth of surface roughness.