An Experimental Study on Laminar Heat Transfer in Flat Aluminum Extruded Tubes Having Small Hydraulic Diameter

  • Kim, Nae-Hyun (Department of Mechanical Engineering, University of Incheon) ;
  • Ham, Jung-Ho (Department of Mechanical Engineering, University of Incheon) ;
  • Kim, Do-Young (Department of Mechanical Engineering, University of Incheon)
  • Published : 2007.06.30


Laminar heat transfer experiments were conducted in flat extruded aluminum tubes. Three different flat tubes-two with smooth inner channel, one with micro-finned inner channel-were tested. Smooth tube data were in reasonable agreement with the predictions by simplified theoretical models. The heat transfer coefficients of the micro-fin tube were significantly smaller than those of the smooth tube. The reason was attributed to the decelerating flow in the inter-fin region. Heat transfer correlations were developed from the data.



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