Performance Enhancement of Solar Thermal Systems Using Nanofluids: A Review

Abstract

Solar evacuated tubes are promising solar thermal devices used for harnessing solar energy. However, improving their efficiency and heat transfer characteristics is crucial for enhancing their overall performance. Nanofluids, and nanoparticles are suspensions in a base fluid, exhibit unique thermodynamic properties that can significantly improve in heat transfer efficiency of solar thermal systems. This review paper provides a comprehensive overview in the recent advances and potential applications of nanofluids in solar evacuated tubes. Those key factors influencing heat transfer enhancement in nanofluids, including particle volume fraction, base fluid selection, particle size, and nanoparticle characteristics, are discussed in detail. Moreover, various experimental techniques and numerical models used to research the heat transfer mechanisms in nanofluids for solar evacuated tubes are reviewed. Additionally, the prospects and challenges of utilizing nanofluids in solar thermal applications are addressed, highlighting areas for further research and development.