Advanced

Measurement of radiation distribution on the absorber in an asymmetric CPC collector

Adsten, M; Hellström, Bengt LU and Karlsson, B (2004) In Solar Energy 76(1-3). p.199-206
Abstract
A method to estimate the annual collected energy and the annual average optical efficiency factor is suggested. The radiation distribution on the absorber of an asymmetric CPC collector with a flat bi-facial absorber is measured for three different absorber mounting angles using a photo diode. The annual optical efficiency factors and a relative measure of the annual collected energy are determined for collectors with the absorber fin thickness 0.5 and 1 mm, and for a collector with a teflon convection suppression film mounted around the absorber. With the local optical efficiency factors and the annual incident solar energy distribution considered, the analysis indicates that the energy gain for a mounting angle of 20 is higher than for a... (More)
A method to estimate the annual collected energy and the annual average optical efficiency factor is suggested. The radiation distribution on the absorber of an asymmetric CPC collector with a flat bi-facial absorber is measured for three different absorber mounting angles using a photo diode. The annual optical efficiency factors and a relative measure of the annual collected energy are determined for collectors with the absorber fin thickness 0.5 and 1 mm, and for a collector with a teflon convection suppression film mounted around the absorber. With the local optical efficiency factors and the annual incident solar energy distribution considered, the analysis indicates that the energy gain for a mounting angle of 20 is higher than for a collector with 65 absorber mounting angle. The annual collected energy is increased with 6-8% if the absorber fin thickness is increased from 0.5 to 1 mm. The annual average optical efficiency factor is relatively independent of the absorber mounting angle. It was found to be 0.87-0.88 for a collector with a 0.5 mm thick absorber fin and 0.92 for a collector with a 1 mm thick absorber fin or for a collector with 0.5 mm thick absorber fin with a teflon convection suppression film added. The low annual average optical efficiency factor is not caused by the uneven irradiance distribution but by the relatively high U-L-values. (C) 2003 Elsevier Ltd. All rights reserved. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Solar Energy
volume
76
issue
1-3
pages
199 - 206
publisher
Elsevier
external identifiers
  • wos:000188391600027
  • scopus:0347051719
ISSN
0038-092X
DOI
10.1016/j.solener.2003.08.024
language
English
LU publication?
yes
id
87af9f1b-e5ae-49fb-860b-bd91a1544ffd (old id 288902)
date added to LUP
2007-08-28 13:35:33
date last changed
2017-01-01 06:37:16
@article{87af9f1b-e5ae-49fb-860b-bd91a1544ffd,
  abstract     = {A method to estimate the annual collected energy and the annual average optical efficiency factor is suggested. The radiation distribution on the absorber of an asymmetric CPC collector with a flat bi-facial absorber is measured for three different absorber mounting angles using a photo diode. The annual optical efficiency factors and a relative measure of the annual collected energy are determined for collectors with the absorber fin thickness 0.5 and 1 mm, and for a collector with a teflon convection suppression film mounted around the absorber. With the local optical efficiency factors and the annual incident solar energy distribution considered, the analysis indicates that the energy gain for a mounting angle of 20 is higher than for a collector with 65 absorber mounting angle. The annual collected energy is increased with 6-8% if the absorber fin thickness is increased from 0.5 to 1 mm. The annual average optical efficiency factor is relatively independent of the absorber mounting angle. It was found to be 0.87-0.88 for a collector with a 0.5 mm thick absorber fin and 0.92 for a collector with a 1 mm thick absorber fin or for a collector with 0.5 mm thick absorber fin with a teflon convection suppression film added. The low annual average optical efficiency factor is not caused by the uneven irradiance distribution but by the relatively high U-L-values. (C) 2003 Elsevier Ltd. All rights reserved.},
  author       = {Adsten, M and Hellström, Bengt and Karlsson, B},
  issn         = {0038-092X},
  language     = {eng},
  number       = {1-3},
  pages        = {199--206},
  publisher    = {Elsevier},
  series       = {Solar Energy},
  title        = {Measurement of radiation distribution on the absorber in an asymmetric CPC collector},
  url          = {http://dx.doi.org/10.1016/j.solener.2003.08.024},
  volume       = {76},
  year         = {2004},
}