Solar thermal collectors are systems that allow for the use of solar energy in thermal applications. These collectors utilize a heat transfer fluid to transport absorbed solar radiation to applications where they are needed. Scientists in a bid to improve the conversion efficiency of solar collectors have suggested different collector designs and improved collector materials. Over the last 25 years, the study of nanofluids and their applications have revolutionized material science, and nanotechnology has found applications in improving solar collector materials. This article reviews the impact of different nanomaterials on the efficiency of solar collectors. The study also outlines the limitations of applying nanofluids and discusses the long-term challenges of their application to solar collectors. Nanofluids have the potential to improve the overall efficiency of most solar collectors, however, the full potential of nanofluids in heat transfer applications cannot be completely achieved until some of the questions regarding hysteresis, stability, and the overall predictability of nanofluids are answered.

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太阳能集热器中的纳米流体：回顾和局限性

太阳能集热器是允许在热应用中使用太阳能的系统。这些收集器利用传热流体将吸收的太阳辐射传输到需要它们的应用中。为了提高太阳能集热器的转换效率，科学家们提出了不同的集热器设计和改进的集热器材料。在过去的 25 年中，对纳米流体及其应用的研究已经彻底改变了材料科学，纳米技术在改进太阳能收集器材料方面得到了应用。本文综述了不同纳米材料对太阳能集热器效率的影响。该研究还概述了应用纳米流体的局限性，并讨论了将其应用于太阳能集热器的长期挑战。