Study on periodic thermal-switching behavior of flat heat pipe

Shigeki Hirasawa, Tatsuya Nakamu, Tsuyoshi Kawanami, Katsuaki Shirai

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

The coupling of the electrocaloric effect in thin films with thermal switches has the potential to be used for efficient refrigeration. We studied the unsteady heat transfer performance and periodic thermal-switching behavior of a flat heat pipe to transfer cold energy from a changing heat source. The condenser of the flat heat pipe was the changing heat source and changed from -20 W to +20 W every 5 s. The temperature of the condenser surface changed in accordance with the heat generation of the heat source. The evaporator was a plate with a mesh wick attached to a water-flow pipe. Cold energy transferred from the condenser surface to the evaporator surface only when the temperature of the condenser surface was lower than that of the evaporator surface. We analyzed the unsteady temperature change and heat transfer performance of the flat heat pipe by numerical simulation. The analytical results showed that it was necessary to have two thermal switches to separate the heat energy and cold energy of the changing heat source. Also, it was important to reduce the thermal resistance and heat capacity of the evaporator surface to improve the unsteady heat transfer performance of the heat pipe. Next, we measured the unsteady heat transfer performance of the flat heat pipe experimentally. The experimental results showed that the thermal-switching behavior was observed when the heat generation of the heat source changed every 5 s.

Original languageEnglish
Title of host publicationHeat Transfer and Thermal Engineering
PublisherAmerican Society of Mechanical Engineers (ASME)
Volume8B-2015
ISBN (Electronic)9780791857502
DOIs
Publication statusPublished - 2015
Externally publishedYes
EventASME 2015 International Mechanical Engineering Congress and Exposition, IMECE 2015 - Houston, United States
Duration: 2015 Nov 132015 Nov 19

Other

OtherASME 2015 International Mechanical Engineering Congress and Exposition, IMECE 2015
CountryUnited States
CityHouston
Period15/11/1315/11/19

Fingerprint

Heat pipes
Evaporators
Heat transfer
Heat generation
Switches
Hot Temperature
Condensers (liquefiers)
Pipe flow
Refrigeration
Heat resistance
Temperature
Specific heat
Thin films

Keywords

  • Electrocaloric Effect
  • Heat pipe
  • Peltier Device
  • Thermal Conductance
  • Thermal Control

ASJC Scopus subject areas

  • Mechanical Engineering

Cite this

Hirasawa, S., Nakamu, T., Kawanami, T., & Shirai, K. (2015). Study on periodic thermal-switching behavior of flat heat pipe. In Heat Transfer and Thermal Engineering (Vol. 8B-2015). American Society of Mechanical Engineers (ASME). https://doi.org/10.1115/IMECE2015-50158

Study on periodic thermal-switching behavior of flat heat pipe. / Hirasawa, Shigeki; Nakamu, Tatsuya; Kawanami, Tsuyoshi; Shirai, Katsuaki.

Heat Transfer and Thermal Engineering. Vol. 8B-2015 American Society of Mechanical Engineers (ASME), 2015.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Hirasawa, S, Nakamu, T, Kawanami, T & Shirai, K 2015, Study on periodic thermal-switching behavior of flat heat pipe. in Heat Transfer and Thermal Engineering. vol. 8B-2015, American Society of Mechanical Engineers (ASME), ASME 2015 International Mechanical Engineering Congress and Exposition, IMECE 2015, Houston, United States, 15/11/13. https://doi.org/10.1115/IMECE2015-50158
Hirasawa S, Nakamu T, Kawanami T, Shirai K. Study on periodic thermal-switching behavior of flat heat pipe. In Heat Transfer and Thermal Engineering. Vol. 8B-2015. American Society of Mechanical Engineers (ASME). 2015 https://doi.org/10.1115/IMECE2015-50158
Hirasawa, Shigeki ; Nakamu, Tatsuya ; Kawanami, Tsuyoshi ; Shirai, Katsuaki. / Study on periodic thermal-switching behavior of flat heat pipe. Heat Transfer and Thermal Engineering. Vol. 8B-2015 American Society of Mechanical Engineers (ASME), 2015.
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