Study of Thermal and Hydrodynamic Performance of a Parabolic Trough Solar Collector Using Hybrid MWCNT/Fe3O4- Therminol VP-1 Nanofluid

In the present study, the performance of a parabolic trough solar collector using a hybrid nanofluid and its comparison with a mono nanofluid and a base fluid were theoretically investigated based on a thermal model. Therminol VP-1 was selected as the base fluid and Fe3O4 and Nanocomposite Multi-walled carbon nanotubes- Fe3O4 were selected as the nanoparticles. The fluid flow inside the absorber tube of the collector is assumed to be turbulent. The rsults showed that the energy and exergy efficiencies using hybrid and mono nanofluids were higher than the base fluid. However, their amount using of hybrid nanofluid was slightly less than that of mono nanofluid. The highest enhancement in energy efficiency for hybrid and mono nanofluids compared with the base fluid was equal to 2.17% and 2.22% respectively. Also, the highest enhancement in exergy efficiency was 1.49% and 1.58% respectively. On the other hand, the friction factor of mono nanofluid in average was about 7% higher than that of hybrid nanofluid. The results showed that the thermal-hydrodynamic efficiency (performance evaluation criterion) of the collector (performance evaluation criterion) using hybrid nanofluid was higher than that of mono nanofluid.