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Reduction of the Wet Surface Heat Transfer Coefficients from Experimental Data  

Kim, Nae-Hyun (Department of Mechanical Engineering, University of Incheon)
Sim, Yong-Sub (Graduate School, University of Incheon)
Publication Information
International Journal of Air-Conditioning and Refrigeration / v.12, no.1, 2004 , pp. 37-49 More about this Journal
Abstract
Four different data reduction methods for the heat transfer coefficients from experimental data under dehumidifying conditions are compared. The four methods consist of two heat and mass transfer models and two fin efficiency models. Data are obtained from two heat exchanger samples having plain fins or wave fins. Comparison of the reduced heat transfer coefficients revealed that the single potential heat and mass transfer model yielded the humidity-independent heat transfer coefficients. Two fin efficiency models-enthalpy model and humidity model-yielded approximately the same fin efficiencies, and accordingly approximately the same heat transfer coefficients. The heat transfer coefficients under wet conditions were approximately the same as those of the dry conditions for the plain fin configuration. For the wave fin configuration, however, wet surface heat transfer coefficients were approximately 12% higher. The pressure drops of the wet surface were 10% to 45% larger than those of the dry surface.
Keywords
Wet surface; Dehumidification; Heat transfer coefficient; Data reduction; Air-side;
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