• 제목/요약/키워드: 봉다발

검색결과 95건 처리시간 0.029초

대형 2차 와류에 의한 봉다발 부수로에서의 난류 열전달 향상에 관한 실험적 연구 (Experiment of Turbulent Heat Transfer Performance Enhancement in Rod Bundle Subchannel by the Large Scale Vortex Flow)

  • 서귀현;최영돈
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.1592-1597
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    • 2004
  • Experimental studies were carried out to confirm the turbulent enhancement of the cooling system of nuclear reactor by large scale vortex generation in nuclear fuel rod bundle. The large scale vortex motions were generated by rearranging the inclination angles of mixing vanes to the coordinate directions. Experimental studies were carried out at Reynolds Number 60,000 with hydraulic condition. Normal variations of mean velocity and turbulent intensity in the rod bundle subchannel were measured by the 2-color LDV measurement system. The turbulence generated by split mixing vanes has small length scales so that they maintain only about 10DH after the spacer grid. On the other hand, the turbulences generated by the large scale vortex continue more and remain up $25D_{H}$ after the spacer grid.

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가열 봉다발의 난류 열전달에 대한 전산유체역학 해석 (CFD Analysis of Turbulent Heat Transfer in a Heated Rod Bundle)

  • 인왕기;오동석;전태현
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 추계학술대회
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    • pp.598-603
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    • 2003
  • A CFD analysis has been performed to investigate turbulent heat transfer in a triangular rod bundle with a pitch-to-diameter ratio(P/D) of 1.06. Anisotropic turbulence models predicted the turbulence-driven secondary flow in the triangular subchannel and the distributions of time mean velocity and temperature showing significantly improved agreement with the measurements over the linear standard ${\kappa}-{\varepsilon}$. The anisotropic turbulence models predicted turbulence structure in large flow region fairly well but could not predict the very high turbulent intensity of azimuthal velocity observed in narrow flow region(gap).

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순환우라늄을 사용한 중수로 출력증강에 관한 연구

  • 민병주;석수동;심기섭;김봉기
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1998년도 춘계학술발표회논문집(1)
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    • pp.175-180
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    • 1998
  • 중수로에 0.88 w/o 의 순환 핵연료를 사용하여 기존 중수로의 출력을 증강시키는 방안이 모색되었다. 기존 중수로와 양립하여야 하므로, 37봉 핵연료 다발과 CANFLEX 핵연료다발에 대한 격자 특성 계산과 노심 계산을 수행하였다. 열수력 여유도 증가와 고연소도 핵연료를 위하여 개발한 개량 핵연료 (CANFLEX)를 사용하면 원자로의 임계채널출력 (CCP)이 5 % 이상 증대하므로, 기존 원자로의 총 출력을 같은 열수력 한계 내에서 5 % 증가시킬 수 있다. 또한 개량 핵연료 다발에 순환우라늄을 사용하면 기존 월성 원자로의 구조 변화 없이 노심 출력분포의 재 분포에 의하여 15 % 까지 출력을 증강할 수 있다고 평가되었다.

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CUPID 코드를 활용한 2×2 봉다발 부수로 유동 해석 (ASSESSMENT OF THE CUPIDCODE APPLICABILITY TO SUBCHANNEL FLOW IN 2×2 ROD BUNDLE)

  • 이재룡;박익규;김정우
    • 한국전산유체공학회지
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    • 제21권4호
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    • pp.71-77
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    • 2016
  • The CUPID code is a transient, three-dimensional, two-fluid, thermal-hydraulic code designed for a component-scale analysis of nuclear reactor components. The primary objective of this study is to assess the applicability of CUPID to single-phase turbulent flow analyses of $2{\times}2$ rod bundle subchannel. The bulk velocity at the inlet varies from 1.0 m/s up to 2.0 m/s which is equivalent to the fully turbulent flow with the range of Re=12,500 to 25,000. Adiabatic single-phase flow is assumed. The velocity profile at the exit region is quantitatively compared with both experimental measurement and commercial CFD tool. Three different boundary conditions are simulated and quantitatively compared each other. The calculation results of CUPID code shows a good agreement with the experimental data. It is concluded that the CUPID code has capability to reproduce the turbulent flow behavior for the $2{\times}2$ rod bundle geometry.