에너지공학 (Journal of Energy Engineering)

  • 제20권1호
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  • Pages.44-53
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  • 2011
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  • 1598-7981(pISSN)
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  • 2713-7074(eISSN)
한국에너지학회 (The Korean Society for Energy)
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경사진 사각형 공간내의 자연대류 열전달

Natural Convection Heat Transfer in Inclined Rectangular Enclosures

  • 장병훈 (인천대학교 공과대학 기계시스템공학부)
  • 투고 : 2010.06.30
  • 심사 : 2011.01.25
  • 발행 : 2011.03.31
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⟨ 이전 논문 다음 논문 ⟩

초록

본 논문에서는 마주보는 두 벽면들이 서로 다른 온도로 유지되는 2차원 사각형 공간 내 공기의 층류 자연대류를 수치해석 방법을 사용하여 $10^6$의 Rayleigh 수까지 조사하였다. 사각공간의 폭과 높이의 비가 1, 2, 4인 경우와 $0^{\circ}{\leq}{\theta}{\leq}90^{\circ}$의 경사각도 범위에서 계산을 수행하였다. $10^3{\leq}Ra{\leq}10^6$의 범위에서 공간의 경사각도가 유동 구조와 열전달에 미치는 영향을 각 종횡비에 대하여 조사하였다. 작은 종횡비의 경우에는 공간 구석에서 발달되는 2차 유동 셀들이 총괄 열전달의 감소를 초래하는 것으로 나타났으며, 큰 종횡비의 경우에는 3개의 유동 셀이 1개로 전이되는 과정에서 스텝모양과 비슷한 열전달의 급 감소가 일어났다. 수직의 경우인 ${\theta}=90^{\circ}$에 대해서 새로운 평균 Nusselt 수 상관식이 제공되었다.

The laminar natural convection of air in 2-D rectangular enclosure in which two opposing isothermal walls were kept at different temperatures is investigated numerically for Rayleigh number up to $10^6$. Computations were performed for the width-to-height ratios of 1, 2, and 4, and for the inclination angle range of $0^{\circ}{\leq}{\theta}{\leq}90^{\circ}$. For each aspect ratio, the influence of the inclination angle on the flow patterns and heat transfer rates were examined for $10^3{\leq}Ra{\leq}10^6$. It is found that the growth of secondary flow in the corners led to the decrease in overall heat transfer for small aspect ratio case, and the transition from a three-cell structure to a unicell flow pattern in large aspect ratio led to a step-like change in heat transfer. A new correlation of mean Nusselt number is presented for the vertical case of ${\theta}=90^{\circ}$.

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참고문헌

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피인용 문헌

  1. Numerical Simulation of Heat Transfer in Chip-in-Board Package vol.37, pp.1, 2013, https://doi.org/10.3795/KSME-B.2013.37.1.075