Thermal Characterization of Flat Plate Solar Collector Using Titanium Dioxide Nanofluid

The thermal performance of flat plate collectors (FPCs) using titanium dioxide (TiO2) nanofluids is analyzed numerically using fluent and SolTrace. The solar ray tracing is performed on SolTrace to obtain the average solar flux on the absorber plate in FPC. The numerical study is conducted on the flat plate solar collector with an aperture width of 200 mm and a single absorber tube of 12.7 mm inner diameter. The numerical simulation on fluent is performed for TiO2 nanofluids with a percentage volume of 0%, 2%, 3%, and 4% TiO2 in Therminol as a heat transfer fluid (HTF). The study also includes the effect of the inlet temperature of nanofluids on the thermohydraulic performance of solar FPC. The result shows a 56% drop in thermal efficiency with a temperature increase from 300 to 353 K. However, changes in the Nusselt number (Nu) and convective heat transfer rate were found to be negligible. The analysis also includes the effect of the Reynolds number (Re) on thermal efficiency and friction factor (f) for different volume fractions of TiO2 in Therminol. A 22.2% increase in thermal efficiency and a 17.5% increase in friction factor are found for a 4% volume fraction of TiO2 in Therminol at a Reynolds number of 720. However, a 17.3% increase in thermal efficiency is found for a 4% volume fraction of TiO2 at a higher Reynolds number of 1080.