Thermal Science 2011 Volume 15, Issue 2, Pages: 457-465
https://doi.org/10.2298/TSCI110222051B
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Numerical simulation of the air flow around the arrays of solar collectors
Bakić Vukman (Department of Thermal Engineering and Energy, Institute of Nuclear Sciences - Vinca, Belgrade)
Živković Goran (Department of Thermal Engineering and Energy, Institute of Nuclear Sciences - Vinca, Belgrade)
Pezo Milada L. (Department of Thermal Engineering and Energy, Institute of Nuclear Sciences - Vinca, Belgrade)
This paper deals with the numerical simulation of air around the arrays of
flat plate collectors and determination of the flow field, which should
provide a basis for estimating a convective heat losses, a parameter which
influences their working characteristics. Heat losses are the result of the
reflection on the glass, conductive losses at the collector’s absorber plate,
radiation of the absorber plate and convective losses on the glass. Wind
velocity in the vicinity of the absorber plate depends on its position in the
arrays of collectors. Results obtained in the numerical simulation of flow
around collectors were used as boundary conditions in modeling of
thermal-hydraulic processes inside the solar collector. A method for coupling
thermal-hydraulic processes inside the collector with heat transfer from
plate to tube bundle was developed, in order to find out the distribution of
the temperature of the absorber plate and the efficiency of the flat plate
collectors. Analyses of flow around arrays of collectors are preformed with
RNG k - ε model. Three values for free-stream velocity were analysed, i.e. 1
m/s, 5 m/s and 10 m/s, as well as two values for the angle between the ground
and the collector (20° and 40°). Heat transfer coefficient was determined
from the theory of boundary layer. Heat transfer inside the plate cavity was
analyzed assuming constant intensity of radiation.
Keywords: solar collector, wind force, turbulent flow, CFD