An Analysis of the Impact of a Nanoparticle's Sizing on the Effectiveness of Solar Collector Based on Nanofluids

Improving the thermal efficiency of flat-plate solar collectors increases the thermal energy that is saved. Using a nanofluid instead of a base fluid enhances thermal performance. To evaluate the thermal performance of nanofluid in a solar collector by adding nanoparticles and their influence, such as particle shape, particle sizes, and particle concentration on thermal properties. This study explored the effect of silicon dioxide (SiO2) nanoparticle size on these parameters on the thermal performance of an experimental flat plate solar collector. The investigation of the effect of particle sizes on collector efficiency is a highlight of this study. It is observed that decreasing the size of the nanoparticles results in the enhancement of the efficiency of the flat plate solar collector. An experiment was conducted at three nanoparticle sizes (10 nm, 40 nm, and 90 nm), spherical shape, and particle concentration 0.1 % dissolved with distilled water (DW) to produce working fluid homogenous nanofluid. Under Iraqi climate conditions, the test was carried out at different flow rates (10, 15, 20 1/h). ASHRAE Standard No. 93–2010 was utilized to determine the solar collector's thermal effectiveness. The results showed that the maximum efficiency was roughly 73.1, absorbed energy parameter FR
$(\tau \alpha)$
increased, and thermal efficiency increased by approximately 12 % compared with distilled water at an increased flow rate at 20 1/h and decreased particle size at 10 nm