Flat plate solar collectors waste a massive part of the heat accumulated near the contact region, mainly due to poor thermal characteristics of working fluid. The demanding power for pumping the flow through the pipes seems a permanent concern in solar collectors. Also, active methods seem not to be applicable in such systems due to the external energy requirement and cost associated with it. An innovative and simple technique is considered here to eliminate such deficiencies all at once by equipping the flat plate collector with rotary absorber pipes and Fe₃O₄/water nanofluid. Results indicate that the applied method improves the convection mechanism in each pipe by mixing the accumulated heat in the whole flow regions and saves more available solar energy. It also reduces the pressure drop by preparing a slip flow condition inside the pipes, thereby reducing the consuming pumping power. Results also reveal that by dispersing 2% Fe₃O₄ in water and utilizing rotary pipes one can restore around 1.65% and 10.44% of the energy loss of the collector, respectively. In other words, additional energy of 120.16 W can be stored by equipping a flat plate solar collector with rotary tubes and Fe₃O₄/water nanofluid. Also, equipping the collector by both rotary pipes and nanofluid causes 5.83% and 3.21% enhancement in energy and exergy efficiencies, respectively. The reported results substantiate that the required power for operating the employed method can be provided by the collector itself, which makes the proposed technique more cost-effective.

平板太阳能集热器浪费了在接触区域附近积聚的大部分热量，这主要是由于工作流体的热特性差所致。在太阳能集热器中，用于泵送流经管道的高功率功率似乎是一个永久性的问题。而且，由于外部能量需求和与之相关的成本，主动方法似乎不适用于此类系统。在这里，考虑了一种创新且简单的技术，即通过为平板集热器配备旋转吸收器管和Fe ₃ O _4来一次消除这些缺陷。/水纳米流体。结果表明，所应用的方法通过在整个流动区域中混合积聚的热量来改善每个管道的对流机制，并节省更多的可用太阳能。通过准备管道内部的滑流状态，还可以减少压降，从而降低消耗的泵送功率。结果还表明，通过将2％Fe ₃ O ₄分散在水中并使用旋转管，可以分别回收集热器约1.65％和10.44％的能量损失。换句话说，通过为平板太阳能收集器配备旋转管和Fe ₃ O _4，可以存储120.16 W的额外能量/水纳米流体。同样，通过旋转管和纳米流体为集热器配备分别使能量和火用效率分别提高5.83％和3.21％。所报告的结果证实，可以通过收集器本身来提供操作所采用的方法所需的功率，这使得所提出的技术更具成本效益。