Addition of a small amount of nanoparticles to the working fluids of a parabolic trough collector does not only enhance the heat transfer properties and thermal conductivity of basefluid but also improves the thermal efficiency of the system. The current investigation presents a comparative analysis of experimental performance of a conventional parabolic trough collector and direct absorption parabolic trough collector for capturing solar thermal energy. Two separate nanomaterials, Al₂O₃ (with high scattering properties) and CuO (with high absorption properties), were selected for the preparation of the hybrid nanofluids. A customized experimental setup was developed to evaluate their photothermal performance. The nanofluid samples in the concentration range of 0.01–0.5 wt% were investigated under a natural solar flux. Thermal efficiency of conventional parabolic trough collector was increased by 31% using hybrid nanofluid as compared to basefluid. The thermal efficiency enhancement of direct absorption parabolic trough collector was observed as 19% higher than that of conventional parabolic trough collector due to higher heat transfer rate, solar trapping and volumetric absorption. These binary nanofluids can be potential working fluids in various applications based on solar thermal energy.

向抛物槽收集器的工作流体中添加少量纳米颗粒不仅可以增强基液的传热性能和导热性，还可以提高系统的热效率。当前的研究提出了对常规抛物槽收集器和直接吸收抛物槽收集器用于捕获太阳能的实验性能的比较分析。两种独立的纳米材料Al ₂ O ₃（具有高散射性质）和（具有高吸收性质）CuO被选择用于制备杂化纳米流体。开发了定制的实验装置以评估其光热性能。在自然光通量下研究了浓度范围为0.01–0.5 wt％的纳米流体样品。与基础流体相比，使用杂合纳米流体将常规抛物槽收集器的热效率提高了31％。观察到直接吸收式抛物槽式集热器的热效率比常规抛物槽式集热器的热效率提高了19％，这是由于更高的传热速率，太阳能捕获和体积吸收。这些二元纳米流体在太阳能热的各种应用中可能是潜在的工作流体。