Numerical analysis with experimental validation for thermal performance of flat plate solar water heater using CuO/distilled water nanofluid in closed loop

The thermal performance of a solar flat plate collector incorporating CuO nanofluid as a working medium was examined in the present study. The solar collector with two riser tubes was studied experimentally and the results compared with the numerical outcomes predicted using commercially available Ansys 19.0 software. The solar water heater was examined for water and CuO nanofluid with 0.2 wt% and 0.4 wt% for two different volume flow rates of 0.5 and 1 lit/min. The present study claims that the instantaneous thermal efficiency for 0.2 wt% and 0.4 wt% increased by 12.01 % and 7.56 %, respectively, compared to water as a working medium. The effect of CuO/distilled water nanofluid on the collector's efficiency was also numerically studied using a two-phase CFD model. It is observed that the CFD and experimental results show good agreement with each other, with a maximum error of 5.84 % and 4.29 % for the nanofluid and water as working fluids, respectively.