Thermal Property Measurement of Nanofluid Droplets with Temperature Gradients
In this study, the 3ω method was used to determine the thermal conductivity of nanofluids (ethylene glycol containing multi-walled carbon nanotubes (MWCNTs)) with temperature gradients. The thermal modeling of the traditional 3ω method was modified to measure the spatial variation...
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-01-01
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| Series: | Energies |
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| Online Access: | https://www.mdpi.com/1996-1073/13/1/244 |
| _version_ | 1798039566433648640 |
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| author | Dong-Wook Oh |
| author_facet | Dong-Wook Oh |
| author_sort | Dong-Wook Oh |
| collection | DOAJ |
| description | In this study, the 3ω method was used to determine the thermal conductivity of nanofluids (ethylene glycol containing multi-walled carbon nanotubes (MWCNTs)) with temperature gradients. The thermal modeling of the traditional 3ω method was modified to measure the spatial variation of thermal conductivity within a droplet of nanofluid. A direct current (DC) heater was used to generate a temperature gradient inside a sample fluid. A DC heating power of 14 mW was used to provide a temperature gradient of 5000 K/m inside the sample fluid. The thermal conductivity was monitored at hot- and cold-side 3ω heaters with a spacing of 0.3 mm. Regarding the measurement results for the hot and cold 3ω heaters, when the temperature gradient was applied, the maximum thermal conductivity difference was determined to be 3% of the original value. By assuming that the thermo-diffusion of MWCNTs was entirely responsible for this difference, the Soret coefficient of the MWCNTs in the ethylene glycol was calculated to be −0.749 K<sup>−1</sup>. |
| first_indexed | 2024-04-11T21:55:39Z |
| format | Article |
| id | doaj.art-355267d3fd5c42b4b5cb91e603c967fc |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-04-11T21:55:39Z |
| publishDate | 2020-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-355267d3fd5c42b4b5cb91e603c967fc2022-12-22T04:01:07ZengMDPI AGEnergies1996-10732020-01-0113124410.3390/en13010244en13010244Thermal Property Measurement of Nanofluid Droplets with Temperature GradientsDong-Wook Oh0Department of Mechanical Engineering, Chosun University, Gwangju 61452, KoreaIn this study, the 3ω method was used to determine the thermal conductivity of nanofluids (ethylene glycol containing multi-walled carbon nanotubes (MWCNTs)) with temperature gradients. The thermal modeling of the traditional 3ω method was modified to measure the spatial variation of thermal conductivity within a droplet of nanofluid. A direct current (DC) heater was used to generate a temperature gradient inside a sample fluid. A DC heating power of 14 mW was used to provide a temperature gradient of 5000 K/m inside the sample fluid. The thermal conductivity was monitored at hot- and cold-side 3ω heaters with a spacing of 0.3 mm. Regarding the measurement results for the hot and cold 3ω heaters, when the temperature gradient was applied, the maximum thermal conductivity difference was determined to be 3% of the original value. By assuming that the thermo-diffusion of MWCNTs was entirely responsible for this difference, the Soret coefficient of the MWCNTs in the ethylene glycol was calculated to be −0.749 K<sup>−1</sup>.https://www.mdpi.com/1996-1073/13/1/244nanofluidsthermal conductivity3ω methodtemperature gradient |
| spellingShingle | Dong-Wook Oh Thermal Property Measurement of Nanofluid Droplets with Temperature Gradients Energies nanofluids thermal conductivity 3ω method temperature gradient |
| title | Thermal Property Measurement of Nanofluid Droplets with Temperature Gradients |
| title_full | Thermal Property Measurement of Nanofluid Droplets with Temperature Gradients |
| title_fullStr | Thermal Property Measurement of Nanofluid Droplets with Temperature Gradients |
| title_full_unstemmed | Thermal Property Measurement of Nanofluid Droplets with Temperature Gradients |
| title_short | Thermal Property Measurement of Nanofluid Droplets with Temperature Gradients |
| title_sort | thermal property measurement of nanofluid droplets with temperature gradients |
| topic | nanofluids thermal conductivity 3ω method temperature gradient |
| url | https://www.mdpi.com/1996-1073/13/1/244 |
| work_keys_str_mv | AT dongwookoh thermalpropertymeasurementofnanofluiddropletswithtemperaturegradients |