Thermal Improvement in Parabolic Trough Solar Collector Using Receiver Tube Design and Nanofluid

Improving the thermal performance of parabolic trough solar collector (PTSC) has been recently a topic of intensive research due to its high advantages, such as a reduction in system size and expense, as well as an improvement in thermal efficiency. Such studies strive for enhancing heat transfer in the receiver portion to reduce heat loss and improve heat transfer to the working fluid. The focus of the recent analysis is an experimental research relevant to the thermal performance of the receiver part. Different enhancement techniques, including nanofluids, the surface modifications and inserts or the two categories mixed, are discussed. The thermophysical properties of nanoparticles play an essential role in the absorption, the extinguishing coefficient, and penetration depth of the nanofluid's solar radiation. Finally, the key findings were presented for each work, and this review may open new horizons for more research in this area.