Experimental Research on the Thermal Performance and Semi-Visualization of Rectangular Flat Micro-Grooved Gravity Heat Pipes
Abstract
:1. Introduction
2. Experimental
2.1. Fabrication of FMGHPs
2.2. Experimental System
2.3. Experimental Conditions
3. Thermal Performance Indicators
4. Results and Discussion
4.1. The Effects of FMGHP Micro-Grooves on Start-Up Time
4.2. The Effects of Micro-Grooves on FMGHPs on Temperature Difference
4.3. The Effects of Micro-Grooves on FMGHPs on Relative Thermal Resistance
4.4. The Effects of Micro-Grooves on FMGHPs on Equivalent Thermal Conductivity
4.5. The Semi-Visualization Comparison of FMGHP and FGHP
5. Conclusions
- (1)
- With the increasing heating load, the start-up time, temperature difference and relative thermal resistance of FMGHPs show a declining trend and the equivalent thermal conductivity is enhanced.
- (2)
- The deeper and narrower micro-grooves show better thermal performance and the optimal rectangular micro-groove dimension among the selected options is determined as 1.2 mm (depth) × 0.4 mm (width) within the experimental range.
- (3)
- The start-up time, temperature difference, relative thermal resistance and equivalent thermal conductivity of FMGHPs are all better than that of the FGHP. The four indicators of FMGHP 3, which has the best thermal performance among the nine FMGHPs, are enhanced by 29%, 66%, 80% and 155%, respectively.
- (4)
- At the same heating load, the liquid–vapor two-phase behaviors in the FMGHP are more intensive. Larger and more bubbles can be observed in the cavity of the FMGHP compared with the observations of the FGHP.
Author Contributions
Funding
Conflicts of Interest
References
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FMGHP Number | Depth (d) | Width (w) | Micro-Groove Length | Micro-groove Number |
---|---|---|---|---|
(mm) | (mm) | (mm) | ||
1 | 0.4 | 0.4 | 200 | 40 |
2 | 0.8 | |||
3 | 1.2 | |||
4 | 0.4 | 0.8 | ||
5 | 0.8 | |||
6 | 1.2 | |||
7 | 0.4 | 1.2 | ||
8 | 0.8 | |||
9 | 1.2 |
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Gou, X.; Zhang, Q.; Li, Y.; Liu, Y.; Liu, S.; Iram, S. Experimental Research on the Thermal Performance and Semi-Visualization of Rectangular Flat Micro-Grooved Gravity Heat Pipes. Energies 2018, 11, 2480. https://doi.org/10.3390/en11092480
Gou X, Zhang Q, Li Y, Liu Y, Liu S, Iram S. Experimental Research on the Thermal Performance and Semi-Visualization of Rectangular Flat Micro-Grooved Gravity Heat Pipes. Energies. 2018; 11(9):2480. https://doi.org/10.3390/en11092480
Chicago/Turabian StyleGou, Xiang, Qiyan Zhang, Yamei Li, Yingfan Liu, Shian Liu, and Saima Iram. 2018. "Experimental Research on the Thermal Performance and Semi-Visualization of Rectangular Flat Micro-Grooved Gravity Heat Pipes" Energies 11, no. 9: 2480. https://doi.org/10.3390/en11092480