Abstract:
Existing Flat plate solar thermal collectors suffers from comparatively low efficiency. This
clearly indicates that further research is still needed in the area to improve efficiency of those
types of collectors by employing different techniques. Therefore this study aims to evaluate how
different parameters like spiral tube arrangement, working fluid flow rate and thermal
characteristics affect the thermal efficiency of a flat plate solar collector. An experimental test is
conducted for five different fluid flow rates. In order to investigate the effect of the fluid thermal
characteristics on the efficiency of the collector water, Cuo and nanofluids with two
different nanoparticle volume concentrations are used. The numerical simulation of the collector
has been performed by means of the Finite Volume Method (FVM) using commercial ANSYS
Fluent 19.2 software. Both the numerical and experimental results showed that the spiral type flat
plate collector shows a greater efficiency than the conventional type of collector. The collector
efficiency was maximum for all the fluid types when the fluid flow rate is fixed at 2L/m. and
generally the efficiency obtained for all the working fluids during the experimental test at the
optimum 2L/m fluid flow rate was 60.3 for water, 66.5 for Cuo nanofluids and the maximum
efficiency belongs for Nano fluid which is 68% at 0.4% nanoparticle volume
concentration. The results obtained from the experimental test as well as the numerical results
are fairly in good agreement with only a maximum of 2.85% deviation that shows the
simulations were quite satisfactory.
Key words: flat plate collector, collector efficiency: spiral tube: nanofluids: finite volume
method.