Effect of Pin Diameter Degressive Gradient on Heat Transfer in a Microreactor with Non-Uniform Pin-Fin Array under Low Reynolds Number Conditions
To improve the efficiency of hydrogen-producing microreactors with non-uniform pin-fin array, the influence of the pin diameter degressive gradient of the non-uniform pin-fin array (NPFA) on heat transfer and pressure drop characteristics is analyzed in this study via numerical simulation under low...
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| Format: | Article |
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MDPI AG
2019-07-01
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| Series: | Energies |
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| Online Access: | https://www.mdpi.com/1996-1073/12/14/2702 |
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| author | Miao Qian Jie Li Zhong Xiang Chao Yan Xudong Hu |
| author_facet | Miao Qian Jie Li Zhong Xiang Chao Yan Xudong Hu |
| author_sort | Miao Qian |
| collection | DOAJ |
| description | To improve the efficiency of hydrogen-producing microreactors with non-uniform pin-fin array, the influence of the pin diameter degressive gradient of the non-uniform pin-fin array (NPFA) on heat transfer and pressure drop characteristics is analyzed in this study via numerical simulation under low Reynolds number conditions. Because correlations in prior studies cannot be used to predict the Nusselt number and pressure drop in the NPFA, new heat transfer and friction factor correlations are developed in this paper to account for the effect of the pin diameter degressive gradient, providing a method for the optimized design of the pin diameter degressive gradient for a microreactor with NPFA. The results show that the Nusselt number and friction factor under a low Reynolds number are quite sensitive to the pin diameter degressive gradient. Based on the new correlations, the exponents of the pin diameter degressive gradient for the friction factor and Nusselt number were 6.9 and 2.1, respectively, indicating the significant influence of the pin diameter degressive gradient on the thermal and hydrodynamic characteristics in the NPFA structure. |
| first_indexed | 2024-04-11T22:04:04Z |
| format | Article |
| id | doaj.art-4deabf8ba06f448a9273bc1a2b10ff21 |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-04-11T22:04:04Z |
| publishDate | 2019-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-4deabf8ba06f448a9273bc1a2b10ff212022-12-22T04:00:47ZengMDPI AGEnergies1996-10732019-07-011214270210.3390/en12142702en12142702Effect of Pin Diameter Degressive Gradient on Heat Transfer in a Microreactor with Non-Uniform Pin-Fin Array under Low Reynolds Number ConditionsMiao Qian0Jie Li1Zhong Xiang2Chao Yan3Xudong Hu4Zhejiang Provincial Key Lab of Modern Textile Machinery, Faculty of Mechanical Engineering and Automation, Zhejiang Sci-Tech University, Hangzhou 310018, ChinaZhejiang Provincial Key Lab of Modern Textile Machinery, Faculty of Mechanical Engineering and Automation, Zhejiang Sci-Tech University, Hangzhou 310018, ChinaZhejiang Provincial Key Lab of Modern Textile Machinery, Faculty of Mechanical Engineering and Automation, Zhejiang Sci-Tech University, Hangzhou 310018, ChinaZhejiang Provincial Key Lab of Modern Textile Machinery, Faculty of Mechanical Engineering and Automation, Zhejiang Sci-Tech University, Hangzhou 310018, ChinaZhejiang Provincial Key Lab of Modern Textile Machinery, Faculty of Mechanical Engineering and Automation, Zhejiang Sci-Tech University, Hangzhou 310018, ChinaTo improve the efficiency of hydrogen-producing microreactors with non-uniform pin-fin array, the influence of the pin diameter degressive gradient of the non-uniform pin-fin array (NPFA) on heat transfer and pressure drop characteristics is analyzed in this study via numerical simulation under low Reynolds number conditions. Because correlations in prior studies cannot be used to predict the Nusselt number and pressure drop in the NPFA, new heat transfer and friction factor correlations are developed in this paper to account for the effect of the pin diameter degressive gradient, providing a method for the optimized design of the pin diameter degressive gradient for a microreactor with NPFA. The results show that the Nusselt number and friction factor under a low Reynolds number are quite sensitive to the pin diameter degressive gradient. Based on the new correlations, the exponents of the pin diameter degressive gradient for the friction factor and Nusselt number were 6.9 and 2.1, respectively, indicating the significant influence of the pin diameter degressive gradient on the thermal and hydrodynamic characteristics in the NPFA structure.https://www.mdpi.com/1996-1073/12/14/2702heat transferpin diameter degressive gradientpin-finlow Reynolds numbersingle phase |
| spellingShingle | Miao Qian Jie Li Zhong Xiang Chao Yan Xudong Hu Effect of Pin Diameter Degressive Gradient on Heat Transfer in a Microreactor with Non-Uniform Pin-Fin Array under Low Reynolds Number Conditions Energies heat transfer pin diameter degressive gradient pin-fin low Reynolds number single phase |
| title | Effect of Pin Diameter Degressive Gradient on Heat Transfer in a Microreactor with Non-Uniform Pin-Fin Array under Low Reynolds Number Conditions |
| title_full | Effect of Pin Diameter Degressive Gradient on Heat Transfer in a Microreactor with Non-Uniform Pin-Fin Array under Low Reynolds Number Conditions |
| title_fullStr | Effect of Pin Diameter Degressive Gradient on Heat Transfer in a Microreactor with Non-Uniform Pin-Fin Array under Low Reynolds Number Conditions |
| title_full_unstemmed | Effect of Pin Diameter Degressive Gradient on Heat Transfer in a Microreactor with Non-Uniform Pin-Fin Array under Low Reynolds Number Conditions |
| title_short | Effect of Pin Diameter Degressive Gradient on Heat Transfer in a Microreactor with Non-Uniform Pin-Fin Array under Low Reynolds Number Conditions |
| title_sort | effect of pin diameter degressive gradient on heat transfer in a microreactor with non uniform pin fin array under low reynolds number conditions |
| topic | heat transfer pin diameter degressive gradient pin-fin low Reynolds number single phase |
| url | https://www.mdpi.com/1996-1073/12/14/2702 |
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