Experimental evaluation of heat transfer augmentation and exergy analysis in flat plate solar collector employing mono and hybrid nanofluids
摘要
The heat transfer enhancement in flat plate solar collector (FPSC) can be greatly achieved by the admittance of nanofluids (NFs). This work proposes an experimental investigation to observe the effects of dispersing Al2O3, ZnO, and Al2O3 + ZnO(1:1) nanoparticles in water + ethylene glycol (EG) a base fluid in a 65:35 ratio at different concentrations (0.2, 0.4, 0.6, and 0.8 vol%) on the enhancement of an FPSC. Mass flow rate has an impact on the FPSC's performance in the range of 0.016 kg s−1, 0.033 kg s−1, and 0.05 kg s−1.To examine the optical and structural character of NPs, energy-dispersive X-ray analysis (EDAX) and scanning electron microscopy (SEM) were used. This study addresses the thermophysical characteristics, heat transfer rate, Nusselt number, pumping power, pressure drop, efficiency, and exergy efficiency of FPSC using those mono and hybrid nanofluids (HNF), in comparison with a base fluid. HNF infuse into reference fluid, and the thermal conductivity increases by 71.15%. This improvement was 55.76% for Al2O3/water + EG and 46.15% for ZnO/water + EG NFs, respectively. The heat augmentation of HNF was 78.4% at a flow rate of 0.05 kg s−1, whereas ZnO and Al2O3 NFs had augmentations of 62.15% and 73.84%, respectively. The collector efficiency raised remarkably to 66.7% for HNF, 59% for Al2O3, and 56.5% for ZnO at a mass rate of 0.05 kg s−1.With a mass rate of 0.05 kg s−1, the HNF's exergy efficiency raised by 24.7%, while the Al2O3 and ZnO NFs showed improvements of 21% and 19.5%, respectively, compared to the reference fluid.
Graphical abstract