Friction and Heat Transfer Characteristics of Enhanced Tubes with Internal Ribs

돌기가 있는 거친 표면에서의 관내 마찰 및 열전달 특성

  • 박종익 (경희대학교 기계공학과 대학원) ;
  • 정진희 (LG전선(주) 기계연구소) ;
  • 이영수 (한국에너지기술연구원) ;
  • 강용태 (경희대학교 기계산업시스템공학부)
  • Published : 2005.04.01

Abstract

The objectives of this paper are to study the heat transfer characteristics on enhanced surfaces, to develop experimental correlations of friction factor and Nusselt number, and to provide a guideline for optimum operation conditions at low temperature boiling for practical refrigeration applications. The working fluid (water, EG $30\%$) flows inside the enhanced tube and R134a boils on the outer surface. Two different types of Turbo-B tubes (Tube I and Tube II) are tested in the present study. The results show that Tube I gives a higher heat transfer coefficient with higher friction factor than Tube II. The present study provided experimental correlations for friction factor and heat transfer coefficient with error bands of ${\pm}5\%\;and\;{\pm}\;15\%$, respectively.

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References

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