In the present study, the pure MCM-41- and CuO-doped MCM-41 nanoparticles with various mass fractions of CuO were synthesized and used for the preparation of water-based nanofluids. The obtained nanoparticles were characterized using small-angle X-ray scattering, scanning electron microscopy, transmission electron microscopy and N₂ adsorption/desorption analysis. The thermal conductivity of the water-based nanofluids with various mass fractions of nanoparticles including 0.1, 0.5 and 1 mass% was measured by KD2-Pro thermal analyzer. A new correlation is developed for the thermal conductivity of the nanofluid with a reasonably good accuracy (± 5%) when comparing to the experimental data. The thermal performance of these nanofluids together with hydraulic features such as friction factor and heat transfer coefficient was investigated using a mini-channel heat exchanger. The obtained results revealed that the thermal conductivity can be enhanced by 13.1% which belonged to the nanofluid with 1 mass% of CuO-doped MCM-41 nanoparticles. The maximum heat transfer coefficient enhancement was 31% and belonged to the nanofluid containing 50% CuO@MCM-41 nanoparticles at 0.5 mass%. The performance evaluation criterion (PEC) of the various nanofluids was also calculated, and it was identified that the nanoparticles with 50% CuO@MCM-41 dispersed in water have the largest PEC, 16.7% over the base fluid. The friction factor increases by adding the nanoparticles to the pure water. For example, at Re = 1200, the friction factor increases about 36.84% by using the 50%CuO@MCM-41 nanoparticles with 0.5 mass% as compared with the pure water. The friction factor decreases with increasing the Reynolds number. For example, for 50%CuO@MCM-41 and 0.5 mass%, the friction factor decreases up to 34.17% as the Reynolds number increases in the range of 400–1200.

中文翻译：

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水性氧化铜掺杂MCM-41纳米流体的热性能和热导率新相关性的实验研究

在本研究中，合成了具有不同质量分数的CuO的纯MCM-41和CuO掺杂的MCM-41纳米颗粒，并将其用于制备水基纳米流体。使用小角X射线散射，扫描电子显微镜，透射电子显微镜和N ₂表征获得的纳米颗粒。吸附/解吸分析。通过KD2-Pro热分析仪测量具有0.1质量％，0.5质量％和1质量％的纳米颗粒的各种质量分数的水基纳米流体的热导率。当与实验数据进行比较时，为纳米流体的热导率开发了一种新的相关性，具有相当好的准确性（±5％）。使用微型通道换热器研究了这些纳米流体的热性能以及诸如摩擦系数和传热系数的液压特性。所得结果表明，以1质量％的CuO掺杂的MCM-41纳米颗粒属于纳米流体，其导热率可提高13.1％。最大传热系数提高了31％，属于含有50％CuO @ MCM-41纳米粒子（质量百分比为0.5％）的纳米流体。还计算了各种纳米流体的性能评价标准（PEC），并且确定了分散在水中的CuO @ MCM-41含量为50％的纳米颗粒的PEC最大，超过基础液的16.7％。通过将纳米颗粒添加到纯水中，摩擦系数增加。例如，在Re ＝ 1200时，与纯水相比，通过使用具有0.5质量％的50％CuO @ MCM-41纳米颗粒，摩擦系数增加了约36.84％。摩擦系数随雷诺数的增加而减小。例如，对于50％CuO @ MCM-41和0.5质量％，当雷诺数在400-1200范围内增加时，摩擦系数降低至34.17％。结果表明，分散在水中的CuO @ MCM-41含量为50％的纳米颗粒的PEC最大，比基础液高16.7％。通过将纳米颗粒添加到纯水中，摩擦系数增加。例如，在Re ＝ 1200时，与纯水相比，通过使用具有0.5质量％的50％CuO @ MCM-41纳米颗粒，摩擦系数增加了约36.84％。摩擦系数随雷诺数的增加而减小。例如，对于50％CuO @ MCM-41和0.5质量％，当雷诺数在400-1200范围内增加时，摩擦系数降低至34.17％。结果表明，分散在水中的CuO @ MCM-41含量为50％的纳米颗粒的PEC最大，比基础液高16.7％。通过将纳米颗粒添加到纯水中，摩擦系数增加。例如，在Re ＝ 1200时，与纯水相比，通过使用具有0.5质量％的50％CuO @ MCM-41纳米颗粒，摩擦系数增加了约36.84％。摩擦系数随雷诺数的增加而减小。例如，对于50％CuO @ MCM-41和0.5质量％，当雷诺数在400-1200范围内增加时，摩擦系数降低至34.17％。摩擦系数随雷诺数的增加而减小。例如，对于50％CuO @ MCM-41和0.5质量％，当雷诺数在400-1200范围内增加时，摩擦系数降低至34.17％。摩擦系数随雷诺数的增加而减小。例如，对于50％CuO @ MCM-41和0.5质量％，当雷诺数在400-1200范围内增加时，摩擦系数降低至34.17％。