Heat Transfer and Friction Characteristics of Slit Fin and Tube Heat Exchangers in Wet Conditions

습표면 조건에서 슬릿 핀-튜브 열교환기의 열전달 및 압력강하 특성

  • Published : 2007.01.10

Abstract

Water condensate accumulated on the surface of a fin-and-tube heat exchanger significantly affects its thermal and hydraulic performance. The purpose of this study is to investigate the effect of condensate retention on the air-side heat transfer performance and flow friction. Total 12 samples of slit and plate fin-and-tube heat exchangers with varying fin spacing and number of tube rows are tested under dry and wet conditions. The thermal fluid measurements are made using a psychometric calorimeter. Frontal air velocity varies in the range from 0.7 m/s to 1.5 m/s. Using the experimental data, presented are the heat transfer coefficients in terms of Colburn j-factor and friction factor.

Keywords

References

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