Document Type : Research Paper
Authors
Electromechanical Eng. Dept., University of Technology - Iraq
Abstract
In this study, the effect of vacuum with micro-channel technique
on solar air collector performance is investigated experimentally. Vacuum
space reduces the loss of heat for the absorption plate by conduction and
thus improves the solar collector performance. It has been demonstrated
that the solar collector is evacuated to 0.1 bar of pressure for absorber-tocover spacing of 4cm. An absorber plate was manufactured from Aluminum
metal with 30 rectangular micro-channels (length 0.9, width 0.004, height
0.0008 m) is constructed with measurements facilities of velocity,
temperature and differential pressure. The tests are carried out indoor using
solar simulator. Results showed that the performance of solar collector
increases with vacuum about 2-5% than gained with non-vacuum utilizing a
micro-channel absorber plate-black surface.
Keywords
Main Subjects
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