The photovoltaic/thermal systems with magnetic nanofluid based spectral beam filter would achieve thermal decoupling and utilize the full spectrum to minimize energy loss. The prepared Fe3O4 magnetic nanofluid was introduced into this system as selective absorbing fluid filter. An external magnetic field was added to manipulate the distribution behavior of nanoparticles that affect the optical characteristics of magnetic nanofluids could meet the various application requirements for electrical/thermal output of the photovoltaic/thermal system. The optical properties of magnetic nanofluid with various nanoparticle distribution behaviors under the varying magnetic field were tested by UV–visible spectrophotometric and Finite-Difference Time-Domain simulated respectively. Furthermore, the effect of magnetic nanoparticle concentration and magnetic field strength on the electrical/thermal output performance of the photovoltaic/thermal system was studied. The results show the higher nanoparticle concentration enhances the thermal output of the system but reduces the electrical output, accompanied by a significant reduction in the surface temperature of the cell. Both photothermal and photovoltaic conversion efficiencies are increased below 100mT magnetic field due to the transmission in the response spectrum of monocrystalline silicon cell increase under the formation of chain structure of the nanoparticles. It is concluded that the photothermal, photovoltaic, and total solar energy conversion efficiencies are respectively 59.82%, 13.98%, and 73.75% at 0.0025 wt% concentration under 100 mT magnetic fields, and its function of merit value was increased by 109% compared to the system without spectral beam filter.

中文翻译：

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具有基于磁性纳米流体的光谱光束滤波器的 PV/T 系统的可调谐电/热输出性能


具有基于磁性纳米流体的光谱光束滤波器的光伏/热系统将实现热解耦并利用全光谱来最大限度地减少能量损失。将制备的 Fe3O4 磁性纳米流体引入该系统作为选择性吸收流体过滤器。添加外部磁场来操纵纳米粒子的分布行为，从而影响磁性纳米流体的光学特性，可以满足光伏/热系统的电/热输出的各种应用要求。分别通过紫外可见分光光度法和时域有限差分模拟测试了在不同磁场下具有不同纳米粒子分布行为的磁性纳米流体的光学性质。此外，还研究了磁性纳米颗粒浓度和磁场强度对光伏/热系统电/热输出性能的影响。结果表明，较高的纳米颗粒浓度增强了系统的热输出，但降低了电输出，同时电池表面温度显着降低。由于纳米粒子链状结构的形成，单晶硅电池响应光谱的传输增加，光热和光伏转换效率在100mT磁场以下均有所增加。结果表明，在100 mT磁场下，0.0025 wt%浓度下，光热、光伏和总太阳能转换效率分别为59.82%、13.98%和73.75%，其优值函数较之提高了109%。没有光谱光束过滤器的系统。