Effects of truncated and offset pin-fins on hydrothermal performance and entropy generation in a rectangular microchannel heat sink with variable fluid properties
| Autor: | Yongqi Lan, Kui Huang, Zhenfei Feng, Jinxin Zhang, Zhenjun Hu |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Offset (computer science)
Microchannel Materials science Computer simulation 020209 energy General Chemical Engineering Flow (psychology) 02 engineering and technology Mechanics Condensed Matter Physics 01 natural sciences Atomic and Molecular Physics and Optics 010406 physical chemistry 0104 chemical sciences Entropy (classical thermodynamics) Heat transfer Thermal 0202 electrical engineering electronic engineering information engineering Constant (mathematics) |
| Zdroj: | International Communications in Heat and Mass Transfer. 124:105258 |
| ISSN: | 0735-1933 |
| DOI: | 10.1016/j.icheatmasstransfer.2021.105258 |
| Popis: | A rectangular microchannel with truncated and offset pin-fins is designed, and investigated using numerical simulation. The width (Wc) and height (Hc) of a single smooth microchannel are 0.1 mm and 0.2 mm, respectively. The pin-fin length, width and height (Hr) are 0.06 mm, 0.03 mm and 0–0.2 mm, respectively. The offset value (Wr) of two adjacent pin-fins in width direction of microchannel ranges from 0 to 0.07 mm. The effects of relative height (Hrc = Hr/Hc) and relative offset value (Wrc = Wr/Wc) on hydrothermal performance and entropy generation are analyzed. Results show that increasing pin-fin height usually results in both higher thermal enhancement and flow resistance. Increasing pin-fin offset value properly can enhance heat transfer, but extremely larger offset value leads to decrease of thermal enhancement. The microchannel with Hrc = 0.75 and Wrc = 0.6 yields the maximum overall thermal performance factor of 1.43. The minimum augmentation entropy generation number of 0.31 is obtained in microchannel with Hrc = 0.75 and Wrc = 0.4. From comparison of variable and constant fluid properties, variable fluid properties significantly affect flow and heat transfer performance. Particularly, fluid viscosity plays a key role in fluid properties while others have unobvious effect. |
| Databáze: | OpenAIRE |
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