Document Type : Original Article

Authors

1 Aerospace Engineering Department, Amirkabir University of Technology

2 Mechanical Engineering Department, Dalhousie University, Halifax,Canada

3 Satellite Research Institute, Tehran, Iran

Abstract

Designing flattened miniature heat pipes (FMHPs) for electronic devices is a challenging issue due to high heat flux and limited heat dissipation space. It requires understanding the combined effects of the sintered-grooved wick structure, double heat sources, and flat thickness on heat pipes' thermal efficiency. Therefore, the aim of this study is to numerically investigate the effects of the FMHP with a hybrid wick on the thermal performance of its double heat sources acting as the CPU and GPU in notebook PCs. A transient 3D finite volume method was used to solve the governing equations and assisted boundary conditions. The cylindrical heat pipe with a 200 mm length and 6 mm outside diameter is flattened into 2, 2.5, 3, and 4 mm final thicknesses (FT). The obtained results show that the final critical thicknesses with the lowest thermal resistance are 2.5 and 3 mm for hybrid and grooved wick structures, respectively. Therefore, FMHP with hybrid wicks can be flattened about 8% more. Hybrid wick structures have the best effect on FMHP thermal performance at FT=2.5 mm

Keywords

Main Subjects

Article Title [Persian]

Numerical Study of Flattened Miniature Heat Pipe with Hybrid Porous Wick and Double Heat Sources

Authors [Persian]

  • G. R. Abdizadeh 1
  • Sahar Noori 1
  • Mohammad Saeedi 2
  • Hamidreza Tajik 3

1 Aerospace Engineering Department, Amirkabir University of Technology

2 Mechanical Engineering Department, Dalhousie University, Halifax, Canada

3 Satellite Research Institute, Tehran, Iran

Abstract [Persian]

Designing flattened miniature heat pipes (FMHPs) for electronic devices is a challenging issue due to high heat flux and limited heat dissipation space. It requires understanding the combined effects of the sintered-grooved wick structure, double heat sources, and flat thickness on heat pipes' thermal efficiency. Therefore, the aim of this study is to numerically investigate the effects of the FMHP with a hybrid wick on the thermal performance of its double heat sources acting as the CPU and GPU in notebook PCs. A transient 3D finite volume method was used to solve the governing equations and assisted boundary conditions. The cylindrical heat pipe with a 200 mm length and 6 mm outside diameter is flattened into 2, 2.5, 3, and 4 mm final thicknesses (FT). The obtained results show that the final critical thicknesses with the lowest thermal resistance are 2.5 and 3 mm for hybrid and grooved wick structures, respectively. Therefore, FMHP with hybrid wicks can be flattened about 8% more. Hybrid wick structures have the best effect on FMHP thermal performance at FT=2.5 mm

Keywords [Persian]

  • Flattened heat pipe
  • hybrid wick
  • Thermal resistance
  • Numerical simulation
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