Thermal performance evaluation of thin vapor chamber

Shyy-Woei Chang, K. F. Chiang, W. L. Cai

Research output: Contribution to journalArticle

Abstract

Present study proposes a semi-empirical method to measure the effective thermal conductivities (keff) of a thin vapor chamber (VC). With the liquid-vapor phase change processes as the dominant heat transfer mechanisms in a VC, the keff measurements are expressed as the functions of heat flux and VC orientation. Thermal performance tests measuring the thermal resistances and keff at horizontal and vertical orientations are carried out using three thin VCs of the identical capillary structure with the total thickness of 0.3 mm, 0.4 mm, and 0.5 mm. With the augmented counteracting vapor-liquid flows in these thin VCs, the thermal resistances are raised from a conventional VC. But the thermal spreading performances indexed by keff over the evaporator region remain compatible with the conventional VCs. The sub-cooling effect significantly undermines the thermal spreading performance over the condenser region. When the interior copper pillars are immerged within the excess liquid in condenser, the condenser keff can be less than the thermal conductivity of copper, which phenomenon requires design precautions. While the VC thickness exhibits the noticeable impacts on the thermal performances of the thin VCs, their thermal resistances and evaporator keff are less affected by VC orientation to confirm the anti-gravity properties. A set of empirical correlations evaluating the thermal resistance of these thin VCs are devised for design applications.

Original languageEnglish
Pages (from-to)220-230
Number of pages11
JournalApplied Thermal Engineering
DOIs
Publication statusPublished - 2019 Feb 25

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Vapors
Heat resistance
Evaporators
Thermal conductivity
Liquids
Copper
Hot Temperature
Heat flux
Gravitation
Heat transfer
Cooling

All Science Journal Classification (ASJC) codes

  • Energy Engineering and Power Technology
  • Industrial and Manufacturing Engineering

Cite this

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Thermal performance evaluation of thin vapor chamber. / Chang, Shyy-Woei; Chiang, K. F.; Cai, W. L.

In: Applied Thermal Engineering, 25.02.2019, p. 220-230.

Research output: Contribution to journalArticle

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