Department of Mechanical Engineering, Faculty of Engineering, Vali-e-Asr University of Rafsanjan, Rafsanjan, Iran.
Department of Physics, Faculty of Science, Vali-e-Asr University of Rafsanjan, Rafsanjan, Iran.
Environ Sci Pollut Res Int. 2021 Feb;28(5):5316-5331. doi: 10.1007/s11356-020-10797-x. Epub 2020 Sep 22.
This research was designed to experimentally study the influence of using three metal oxide nanofluids at different high flow rates with various mass concentration of nanoparticles as the working fluid, on the thermal efficiency and pumping power of heat pipe solar collector (HPSC). The volume flow rate of the working fluid was 5, 8, 11, and 14 L/min. Also, mass concentration of nanoparticles was 0.5 and 1.167 g/L. Co-precipitation technique was employed to prepare CuO, AlO, and MgO nanoparticles. The optical and structural characterization of the nanostructure were considered by using X-ray diffraction (XRD), Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), and UV-visible analysis. The thermal performance of the HPSC using metal oxide nanofluids and water was compared with the volume flow rate that varied from 5 to 14 L/min. It was observed that nanofluids improved the collector efficiency between 9 and 20% compared with deionized water. The present results revealed that the maximum efficiency was found to be 83% for a mass concentration of 1.167 g/L of CuO nanofluids and volume flow rate of 14 L/min. The HPSC efficiency shows better improvement with the increasing mass concentration of metal oxide nanoparticles and volume flow rate. Also, the increase rate of the pumping power and pressure drop is less than 0.9% for all of the nanofluids that were used as the working fluids. Results showed that the metal oxide nanofluids are appropriate for increasing the efficiency of HPSC.
这项研究旨在通过实验研究三种金属氧化物纳米流体在不同高流速下，以不同纳米粒子质量浓度作为工作流体，对热管太阳能集热器（HPSC）的热效率和泵送功率的影响。工作流体的体积流量分别为 5、8、11 和 14 L/min。纳米粒子的质量浓度分别为 0.5 和 1.167 g/L。采用共沉淀法制备了 CuO、AlO 和 MgO 纳米粒子。通过 X 射线衍射（XRD）、傅里叶变换红外（FT-IR）、扫描电子显微镜（SEM）和紫外-可见分析，对纳米结构的光学和结构特性进行了考虑。使用金属氧化物纳米流体和水对 HPSC 的热性能进行了比较，体积流量从 5 到 14 L/min 不等。结果表明，与去离子水相比，纳米流体将集热器效率提高了 9%至 20%。目前的结果表明，当质量浓度为 1.167 g/L 的 CuO 纳米流体和体积流量为 14 L/min 时，效率最高可达 83%。HPSC 的效率随着金属氧化物纳米粒子质量浓度和体积流量的增加而更好地提高。此外，所有用作工作流体的纳米流体的泵送功率和压降的增长率均小于 0.9%。结果表明，金属氧化物纳米流体适合提高 HPSC 的效率。
