full2010.pdf - page 1467

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Abstract
This study presents the flow heat transfer characteristics of water in multiport minichannel heat
exchangers. The heat exchanger was designed as a counter flow tube in tube heat exchanger with cold water
flowing in the inner tube and hot water in the gap between the outer and inner tubes. The inner tubes were made
from extruded multiport aluminium with the internal hydraulic diameter of 1.1 mm and the number of channel of
14 channels. The outer tube of heat exchanger was made from circular acrylic tube with an internal hydraulic
diameter of 25.4 mm. The experiments were performed at the Reynolds number between 1000 and 5000, mass
flux of cold water between 980 and 1,990 kg/m2s and saturation temperature ranging from 15 to 25 °C.
The results show that the heat transfer coefficient increase with increasing heat flux and slightly increase with
increasing mass flux, while the decreasing of saturation temperature results in decreasing of heat transfer
coefficient.
Keywords : Heat transfer, Heat exchanger, Multiport minichannel, Mass flux, Heat flux
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