• 제목/요약/키워드: critical energy

검색결과 2,359건 처리시간 0.026초

유한요소법과 샤피충격시험기에 의한 노치각도에 따른 나일론 열가소성 플라스틱 재료의 파괴특성 (Dynamic Fracture Properties of Nylon Thermoplastic Material Depending on Notch Angle with Charpy Impact Machine and Finite Element Method)

  • 박명균;이중원;김태옥
    • 한국가스학회지
    • /
    • 제12권1호
    • /
    • pp.1-6
    • /
    • 2008

  • 샤피충격시험은 동적하중 하에 있는 고분자 재료의 거동을 이해하는데 가장 널리 사용되고 있는 방법이다. 본 연구에서는 샤피충격시험장치에서 얻어지는 파단에너지를 사용하여 나일론 소재 샤피 시편의 노치각도에 따른 에너지 해방율을 구하는 방법을 제시하였다. 또한 샤피충격시험장치를 계장화하여 최대 하중과 파단 시까지 소요되는 에너지 등의 파손인자들을 산출하였다. 그리고 노치각도에 따른 동적파괴 인성치와 유한요소법을 사용하여 중앙집중 하중 하에서 사피 시편의 노치각도에 따른 응력분포를 산출하였다.

  • PDF

EXPERIMENTAL ANALYSES OF SPALLATION NEUTRONS GENERATED BY 100 MEV PROTONS AT THE KYOTO UNIVERSITY CRITICAL ASSEMBLY

  • Pyeon, Cheol Ho;Azuma, Tetsushi;Takemoto, Yuki;Yagi, Takahiro;Misawa, Tsuyoshi
    • Nuclear Engineering and Technology
    • /
    • 제45권1호
    • /
    • pp.81-88
    • /
    • 2013

  • Neutron spectrum analyses of spallation neutrons are conducted in the accelerator-driven system (ADS) facility at the Kyoto University Critical Assembly (KUCA). High-energy protons (100 MeV) obtained from the fixed field alternating gradient accelerator are injected onto a tungsten target, whereby the spallation neutrons are generated. For neutronic characteristics of spallation neutrons, the reaction rates and the continuous energy distribution of spallation neutrons are measured by the foil activation method and by an organic liquid scintillator, respectively. Numerical calculations are executed by MCNPX with JENDL/HE-2007 and ENDF/B-VI libraries to evaluate the reaction rates of activation foils (bismuth and indium) set at the target and the continuous energy distribution of spallation neutrons set in front of the target. For the reaction rates by the foil activation method, the C/E values between the experiments and the calculations are found around a relative difference of 10%, except for some reactions. For continuous energy distribution by the organic liquid scintillator, the spallation neutrons are observed up to 45 MeV. From these results, the neutron spectrum information on the spallation neutrons generated at the target are attained successfully in injecting 100 MeV protons onto the tungsten target.

  • https://doi.org/10.5516/NET.08.2012.003 인용 PDF KSCI KPUBS

고분자 전해질 연료전지를 이용한 Laptop Computer용 전원 공급 장치 (Fuel Cell for the Energy Supply of Laptop Computers)

  • 권부길;이현준;황정태
    • 한국전기화학회:학술대회논문집
    • /
    • 한국전기화학회 2003년도 연료전지심포지움 2003논문집
    • /
    • pp.151-154
    • /
    • 2003

  • The lap-top with a integrated fuel cell system presented here proves that these solutions have a great potential. Though, there are things that have to be improved before they are introduced to the marked. In this system, heat and water management as well as dead end operation are critical issues which must be directly addressed in further research. Both modified stack design and other new cooling techniques are possible ways to continue the work.

  • PDF