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Convective Heat Transfer Correlations for the Compact Heat Exchanger with Circular Tubes and Flat Tubes-Plate Fins

원형관 및 납작관-평판휜 형상의 밀집형 열교환기에 대한 대류열전달 상관관계식

  • Moh, Jeong-Hah (Division of Mechanical & Automotive Engineering, Wonkwang Univ.)
  • 모정하 (원광대학교 기계자동차공학부)
  • Published : 2010.03.01

Abstract

Aspect-ratio-based numerical analysis is carried out to investigate the air-side convective heat transfer characteristics in compact heat exchangers with circular tubes and flat tubes-plate fins. The RNG $k-{\varepsilon}$ model is adopted for turbulence analysis. The numerical analysis is carried out for aspect ratios ranging from 3.06 to 5.44 and for Reynolds numbers ranging from 1,000 to 10,000. The calculated results indicate a correlation between the friction factor and Colburn j factor in the compact heat exchanger system for the range of aspect ratios under consideration. The results obtained for circular tubes and flat tubes-plate fins in this study can be utilized to realize the optimal design of an air conditioning system.

본 연구에서는 열의 수가 세 개인 원형관 및 종횡비가 고려된 납작관-평판휜 형상의 밀집형 열교환기 내 공기의 유동 및 열전달 특성을 RNG $k-{\varepsilon}$ 난류모델을 적용하여 수치적으로 해석하였다. 수치조건의 범위는 원형관인 경우 1,000<$Re_D_h$<10,000이며, 납작관인 경우 1,000<$Re_{D_h}$<10,000 및 3.06$f\;=\;CRe^m_{D_h}$의 형태로, Colburn j 계수는 $j\;=\;CRe^m_{D_h}$ 형태로 상관관계식을 제시하였다. 이러한 상관관계식은 향후 원형관 및 납작관-평판휜 형상의 열교환기 설계시에 기본적인 자료로 충분히 활용될 수 있을 것으로 판단된다.

Keywords

References

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  1. Heat Transfer Characteristics with Changing Distances between Burner and Heat Exchanger vol.35, pp.9, 2011, https://doi.org/10.3795/KSME-B.2011.35.9.933