Investigation of Start-Up Characteristics of Thermosyphons Modified with Different Hydrophilic and Hydrophobic Inner Surfaces
In this paper, the influence of wettability properties on the start-up characteristics of two-phase closed thermosyphons (TPCTs) is investigated. Chemical coating and etching techniques are performed to prepare the surfaces with different wettabilities that is quantified in the form of the contact a...
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| Format: | Article |
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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/1996-1073/13/3/765 |
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| author | Xiaolong Ma Zhongchao Zhao Pengpeng Jiang Shan Yang Shilin Li Xudong Chen |
| author_facet | Xiaolong Ma Zhongchao Zhao Pengpeng Jiang Shan Yang Shilin Li Xudong Chen |
| author_sort | Xiaolong Ma |
| collection | DOAJ |
| description | In this paper, the influence of wettability properties on the start-up characteristics of two-phase closed thermosyphons (TPCTs) is investigated. Chemical coating and etching techniques are performed to prepare the surfaces with different wettabilities that is quantified in the form of the contact angle (CA). The 12 TPCTs are processed including the same CA and a different CA combination on the inner surfaces inside both the evaporator and the condenser sections. For TPCTs with the same wettability properties, the introduction of hydrophilic properties inside the evaporator section not only significantly reduces the start-up time but also decreases the start-up temperature. For example, the start-up time of a TPCT with CA = 28° at 40 W, 60 W and 80 W is 46%, 50% and 55% shorter than that of a TPCT with a smooth surface and the wall superheat degrees is 55%, 39% and 28% lower, respectively. For TPCTs with combined hydrophilic and hydrophobic properties, the start-up time spent on the evaporator section with hydrophilic properties is shorter than that of the hydrophobic evaporator section and the smaller CA on the condenser section shows better results. The start-up time of a TPCT with CA = 28° on the evaporator section and CA = 105° on the condenser section has the best start-up process at 40 W, 60 W and 80 W which is 14%, 22% and 26% shorter than that of a TPCT with smooth surface. Thus, the hydrophilic and hydrophobic modifications play a significant role in promoting the start-up process of a TPCT. |
| first_indexed | 2024-04-11T13:04:20Z |
| format | Article |
| id | doaj.art-e407a398defc435ba9b347c94dbb336a |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-04-11T13:04:20Z |
| publishDate | 2020-02-01 |
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| series | Energies |
| spelling | doaj.art-e407a398defc435ba9b347c94dbb336a2022-12-22T04:22:51ZengMDPI AGEnergies1996-10732020-02-0113376510.3390/en13030765en13030765Investigation of Start-Up Characteristics of Thermosyphons Modified with Different Hydrophilic and Hydrophobic Inner SurfacesXiaolong Ma0Zhongchao Zhao1Pengpeng Jiang2Shan Yang3Shilin Li4Xudong Chen5School of Energy and Power, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212000, ChinaSchool of Energy and Power, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212000, ChinaSchool of Energy and Power, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212000, ChinaSchool of Energy and Power, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212000, ChinaSchool of Energy and Power, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212000, ChinaSchool of Energy and Power, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212000, ChinaIn this paper, the influence of wettability properties on the start-up characteristics of two-phase closed thermosyphons (TPCTs) is investigated. Chemical coating and etching techniques are performed to prepare the surfaces with different wettabilities that is quantified in the form of the contact angle (CA). The 12 TPCTs are processed including the same CA and a different CA combination on the inner surfaces inside both the evaporator and the condenser sections. For TPCTs with the same wettability properties, the introduction of hydrophilic properties inside the evaporator section not only significantly reduces the start-up time but also decreases the start-up temperature. For example, the start-up time of a TPCT with CA = 28° at 40 W, 60 W and 80 W is 46%, 50% and 55% shorter than that of a TPCT with a smooth surface and the wall superheat degrees is 55%, 39% and 28% lower, respectively. For TPCTs with combined hydrophilic and hydrophobic properties, the start-up time spent on the evaporator section with hydrophilic properties is shorter than that of the hydrophobic evaporator section and the smaller CA on the condenser section shows better results. The start-up time of a TPCT with CA = 28° on the evaporator section and CA = 105° on the condenser section has the best start-up process at 40 W, 60 W and 80 W which is 14%, 22% and 26% shorter than that of a TPCT with smooth surface. Thus, the hydrophilic and hydrophobic modifications play a significant role in promoting the start-up process of a TPCT.https://www.mdpi.com/1996-1073/13/3/765thermosyphonstart-up characteristicshydrophilic and hydrophobiccontact angle |
| spellingShingle | Xiaolong Ma Zhongchao Zhao Pengpeng Jiang Shan Yang Shilin Li Xudong Chen Investigation of Start-Up Characteristics of Thermosyphons Modified with Different Hydrophilic and Hydrophobic Inner Surfaces Energies thermosyphon start-up characteristics hydrophilic and hydrophobic contact angle |
| title | Investigation of Start-Up Characteristics of Thermosyphons Modified with Different Hydrophilic and Hydrophobic Inner Surfaces |
| title_full | Investigation of Start-Up Characteristics of Thermosyphons Modified with Different Hydrophilic and Hydrophobic Inner Surfaces |
| title_fullStr | Investigation of Start-Up Characteristics of Thermosyphons Modified with Different Hydrophilic and Hydrophobic Inner Surfaces |
| title_full_unstemmed | Investigation of Start-Up Characteristics of Thermosyphons Modified with Different Hydrophilic and Hydrophobic Inner Surfaces |
| title_short | Investigation of Start-Up Characteristics of Thermosyphons Modified with Different Hydrophilic and Hydrophobic Inner Surfaces |
| title_sort | investigation of start up characteristics of thermosyphons modified with different hydrophilic and hydrophobic inner surfaces |
| topic | thermosyphon start-up characteristics hydrophilic and hydrophobic contact angle |
| url | https://www.mdpi.com/1996-1073/13/3/765 |
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