THE EFFECT OF THE USE OF DIFFERENT COVER MATERIALS ON HEAT TRANSFER IN FLAT SOLAR COLLECTORS

Year 2020, , 829 - 842, 01.10.2020

Mesut Tekkalmaz Çisil Timuralp Zerrin Sert

https://doi.org/10.18186/thermal.800158

Cited By: 1

Abstract

In this study, combined thermal radiation and natural convection heat transfer from glass and plastic
cover flat solar collectors is examined by varying tilt angle and cover materials. The flat-plate solar collector tilt
angle is varied from 0º to 45º. The performance of glass, lexan, and acrylic cover materials is investigated.
Numerical simulations have been performed for various solar collector thicknesses exposed to external ambient
temperature and wind heat transfer coefficient. Continuity, momentum and the energy equations, along with the
Boussinesq approach, are solved with the finite volume method using the SIMPLE algorithm. The cover
temperature and the top loss coefficient are calculated for each cover material, collector tilt angle and bottom
plate temperature, wind heat transfer coefficient and external ambient temperature. The flow and temperature
field are obtained, and the mean convection and radiation Nusselt numbers are calculated for the bottom plate.
The analytically and numerically computed glass cover temperatures are found to be in perfect agreement. The
top loss coefficient of the plastic cover is lower than that of the glass cover. It is determined that with increasing
heat input from the bottom plate, the top loss coefficient and the mean cover material temperature increase
linearly. As the external ambient temperature increases, the top loss coefficient and the cover material
temperature do not present any significant change.

Keywords

Thermal Radiation, Natural Convection, Different Cover Materials, Flat-Plate, Solar Collector

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