Publication detail

Investigation on the thermal performance of flat-plate heat pipes with various working fluids under different inclination angles

Zhang, B. He, Z. Wang, W. Wang, J. Mikulčić, H. Klemeš, J.J.

English title

Investigation on the thermal performance of flat-plate heat pipes with various working fluids under different inclination angles

Type

journal article in Web of Science

Language

en

Original abstract

As one promising high-efficiency equipment, flat-plate heat pipes show an important influence on the thermal management of energy systems. This research experimentally investigates the effects of working fluids (acetone, ethanol, and 1.0 wt% Al2O3 water-based nanofluid), liquid filling ratios (30%, 45%, 60%, and 80%), and inclination angles (0°, 30°, 60°, and 90°) on thermal resistance and equivalent heat transfer coefficient of flat-plate heat pipes under input powers of 15 W, 30 W, 45 W, and 60 W. Results indicate that the flat-plate heat pipe with filling ratio of 60% has the minimum thermal resistance of 2.50 °C/W. Compared with filling ratios of 30%, 45%, and 80%, thermal resistance for 60% filling ratio decreases by 42.8%, 27.8%, and 50.7%. The thermal resistances for inclination angles of 0°, 30°, and 90° increase by 88.9%, 2.97%, and 11.8% compared to that with an inclination angle of 60°. The equivalent heat transfer coefficient of the flat-plate heat pipe increases by 90.8% when the inclination angle increases from 0° to 60° due to an effect of gravity. The heat transfer coefficient of the flat-plate heat pipe decreases by 7.2% when the inclination angle increases from 60° to 90°. The thermal resistance of the flat-plate heat pipe using Al2O3 nanofluid as the working medium decreases by 15.2% and 58.7% compared to those with acetone and ethanol. It is observed that partial dryout occurs when the input power is above 30 W. The evaporator with 5 cm length shows the best heat transfer performance of the flat-plate heat pipe.

English abstract

As one promising high-efficiency equipment, flat-plate heat pipes show an important influence on the thermal management of energy systems. This research experimentally investigates the effects of working fluids (acetone, ethanol, and 1.0 wt% Al2O3 water-based nanofluid), liquid filling ratios (30%, 45%, 60%, and 80%), and inclination angles (0°, 30°, 60°, and 90°) on thermal resistance and equivalent heat transfer coefficient of flat-plate heat pipes under input powers of 15 W, 30 W, 45 W, and 60 W. Results indicate that the flat-plate heat pipe with filling ratio of 60% has the minimum thermal resistance of 2.50 °C/W. Compared with filling ratios of 30%, 45%, and 80%, thermal resistance for 60% filling ratio decreases by 42.8%, 27.8%, and 50.7%. The thermal resistances for inclination angles of 0°, 30°, and 90° increase by 88.9%, 2.97%, and 11.8% compared to that with an inclination angle of 60°. The equivalent heat transfer coefficient of the flat-plate heat pipe increases by 90.8% when the inclination angle increases from 0° to 60° due to an effect of gravity. The heat transfer coefficient of the flat-plate heat pipe decreases by 7.2% when the inclination angle increases from 60° to 90°. The thermal resistance of the flat-plate heat pipe using Al2O3 nanofluid as the working medium decreases by 15.2% and 58.7% compared to those with acetone and ethanol. It is observed that partial dryout occurs when the input power is above 30 W. The evaporator with 5 cm length shows the best heat transfer performance of the flat-plate heat pipe.

Keywords in English

Flat-plate heat pipe; Inclination angle; Liquid filling ratio; Thermal resistance; Working fluid

Released

01.11.2022

Publisher

Elsevier Ltd

ISSN

2352-4847

Number

8

Pages from–to

8017–8026

Pages count

10

BIBTEX


@article{BUT178538,
  author="Jin {Wang} and Jiří {Klemeš},
  title="Investigation on the thermal performance of flat-plate heat pipes with various working fluids under different inclination angles",
  year="2022",
  number="8",
  month="November",
  pages="8017--8026",
  publisher="Elsevier Ltd",
  issn="2352-4847"
}