Thermal Stability and Performance Testing of Oil-based CuO Nanofluids for Solar Thermal Applications
For solar thermal systems, nanofluids have been proposed as working fluids due to their enhanced optical and thermal properties. However, nanoparticles may agglomerate over time, heating and thermal cycles. Even though pristine nanofluids have proven to enhance performance in low-temperature applica...
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-02-01
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| Series: | Energies |
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| Online Access: | https://www.mdpi.com/1996-1073/13/4/876 |
| _version_ | 1811187162394132480 |
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| author | Moucun Yang Sa Wang Yuezhao Zhu Robert A. Taylor M.A. Moghimi Yinfeng Wang |
| author_facet | Moucun Yang Sa Wang Yuezhao Zhu Robert A. Taylor M.A. Moghimi Yinfeng Wang |
| author_sort | Moucun Yang |
| collection | DOAJ |
| description | For solar thermal systems, nanofluids have been proposed as working fluids due to their enhanced optical and thermal properties. However, nanoparticles may agglomerate over time, heating and thermal cycles. Even though pristine nanofluids have proven to enhance performance in low-temperature applications, it is still unclear if nanofluids can meet the reliability requirements of solar thermal applications. For this aim, the present study conducted experiments with several formulations of oil-based CuO nanofluids in terms of their maximum operational temperatures and their stabilities upon cyclic heating. In the samples tested, the maximum temperature ranged from 80 to 150 °C, and the number of heating cycles ranged from 5 to 45, with heating times between 5 to 60 min. The results showed that heating temperature, heating cycles, and heating time all exacerbated agglomeration of samples. Following these experiments, orthogonal experiments were designed to improve the preparation process and the resultant thermal-impulse stability. Thermal properties of these samples were characterized, and thermal performance in an “on-sun” linear Fresnel solar collector was measured. All tests revealed that thermal performance of a solar collecting system could be enhanced with nanofluids, but thermal stability still needs to be further improved for industrial applications. |
| first_indexed | 2024-04-11T13:57:34Z |
| format | Article |
| id | doaj.art-ec4dd29edcfb484a915adcb2c389ddc3 |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-04-11T13:57:34Z |
| publishDate | 2020-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-ec4dd29edcfb484a915adcb2c389ddc32022-12-22T04:20:12ZengMDPI AGEnergies1996-10732020-02-0113487610.3390/en13040876en13040876Thermal Stability and Performance Testing of Oil-based CuO Nanofluids for Solar Thermal ApplicationsMoucun Yang0Sa Wang1Yuezhao Zhu2Robert A. Taylor3M.A. Moghimi4Yinfeng Wang5School of Mechanical and Power Engineering, Nanjing Tech University, Nanjing, China, 30 Puzhu South Rd, Pukou, Nanjing 211816, ChinaSchool of Mechanical and Power Engineering, Nanjing Tech University, Nanjing, China, 30 Puzhu South Rd, Pukou, Nanjing 211816, ChinaSchool of Mechanical and Power Engineering, Nanjing Tech University, Nanjing, China, 30 Puzhu South Rd, Pukou, Nanjing 211816, ChinaSchool of Mechanical and Manufacturing Engineering/School of Photovoltaic and Renewable Energy Engineering, University of New South Wales, Gate 14, Barker St., Kensington, Sydney, NSW 2052, AustraliaDepartment of Design and Engineering, Staffordshire University, Stoke-On-Trent ST4 2DE, UKSchool of Mechanical and Power Engineering, Nanjing Tech University, Nanjing, China, 30 Puzhu South Rd, Pukou, Nanjing 211816, ChinaFor solar thermal systems, nanofluids have been proposed as working fluids due to their enhanced optical and thermal properties. However, nanoparticles may agglomerate over time, heating and thermal cycles. Even though pristine nanofluids have proven to enhance performance in low-temperature applications, it is still unclear if nanofluids can meet the reliability requirements of solar thermal applications. For this aim, the present study conducted experiments with several formulations of oil-based CuO nanofluids in terms of their maximum operational temperatures and their stabilities upon cyclic heating. In the samples tested, the maximum temperature ranged from 80 to 150 °C, and the number of heating cycles ranged from 5 to 45, with heating times between 5 to 60 min. The results showed that heating temperature, heating cycles, and heating time all exacerbated agglomeration of samples. Following these experiments, orthogonal experiments were designed to improve the preparation process and the resultant thermal-impulse stability. Thermal properties of these samples were characterized, and thermal performance in an “on-sun” linear Fresnel solar collector was measured. All tests revealed that thermal performance of a solar collecting system could be enhanced with nanofluids, but thermal stability still needs to be further improved for industrial applications.https://www.mdpi.com/1996-1073/13/4/876oil-based cuo nanofluidstwo-step preparing methodmedium temperaturethermal impulse stabilityorthogonal experiment |
| spellingShingle | Moucun Yang Sa Wang Yuezhao Zhu Robert A. Taylor M.A. Moghimi Yinfeng Wang Thermal Stability and Performance Testing of Oil-based CuO Nanofluids for Solar Thermal Applications Energies oil-based cuo nanofluids two-step preparing method medium temperature thermal impulse stability orthogonal experiment |
| title | Thermal Stability and Performance Testing of Oil-based CuO Nanofluids for Solar Thermal Applications |
| title_full | Thermal Stability and Performance Testing of Oil-based CuO Nanofluids for Solar Thermal Applications |
| title_fullStr | Thermal Stability and Performance Testing of Oil-based CuO Nanofluids for Solar Thermal Applications |
| title_full_unstemmed | Thermal Stability and Performance Testing of Oil-based CuO Nanofluids for Solar Thermal Applications |
| title_short | Thermal Stability and Performance Testing of Oil-based CuO Nanofluids for Solar Thermal Applications |
| title_sort | thermal stability and performance testing of oil based cuo nanofluids for solar thermal applications |
| topic | oil-based cuo nanofluids two-step preparing method medium temperature thermal impulse stability orthogonal experiment |
| url | https://www.mdpi.com/1996-1073/13/4/876 |
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