Derivation and Validation of a Figure of Merit for Loop Heat Pipes with Medium Temperature Working Fluids

Wukchul Joung, Jinho Lee, Sanghyun Lee, Joohyun Lee

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

The working fluids of loop heat pipes (LHPs) play an important role in the operation of the LHPs by influencing the operating temperatures and the heat transfer limits. Therefore, the proper selection of a working fluid is a key practice in LHP fabrication, and there has been a high demand for an appropriate index that enables the quantitative comparison of the steady-state thermal performance of the working fluids. In this work, a figure of merit for LHPs was theoretically derived and experimentally verified. In particular, the pressure losses in the LHP operation were balanced with the saturation pressure difference between the evaporator and the compensation chamber to derive the figure of merit. This derived figure of merit for LHPs successfully predicted the steady-state thermal performance of the tested working fluids within the variable conductance regime. In the constant conductance regime, the differences in the condenser cooling capacity and in the liquid subcooling for different working fluids determined the thermal performance of each working fluid. The limitations and prospects of the proposed figure of merit were discussed in detail.

Original languageEnglish
Article number052901
JournalJournal of Heat Transfer
Volume138
Issue number5
DOIs
Publication statusPublished - 2016 May 1

Fingerprint

heat pipes
working fluids
Heat pipes
figure of merit
derivation
Fluids
Temperature
temperature
evaporators
condensers
Evaporators
operating temperature
chambers
heat transfer
Heat transfer
Cooling
saturation
cooling
Fabrication
fabrication

All Science Journal Classification (ASJC) codes

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

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Derivation and Validation of a Figure of Merit for Loop Heat Pipes with Medium Temperature Working Fluids. / Joung, Wukchul; Lee, Jinho; Lee, Sanghyun; Lee, Joohyun.

In: Journal of Heat Transfer, Vol. 138, No. 5, 052901, 01.05.2016.

Research output: Contribution to journalArticle

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