## THERMAL SCIENCE

International Scientific Journal

### EXPERIMENTAL INVESTIGATION OF HIGHER ALCOHOLS AS SELF-REWETTING FLUIDS IN CLOSED LOOP PULSATING HEAT PIPES

**ABSTRACT**

Heat recovery plays an important role in all energy systems. The dissipation of heat is drastically increasing due to the advancement of electronic components. To cool the electronic components many heat recovery devices are introduced and out of which heat pipes play an important role. Pulsating heat pipe is a new type of heat transfer device which was introduced by Akachi in mid-1990. It is used mainly in the cooling of electronic components because of its potential for removing high heat flux. An experimental study was made to investigate the heat transfer performance of pulsating heat pipe using self-rewetting fluids of high carbon alcohols. The latent heat of vaporization plays an important role in the heat transfer performance of pulsating heat pipe. It was observed that the high carbon alcohols showed a decrease in the latent heat of vaporization. The high carbon alcohols such as 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, and 1-octanol were mixed with the deionized water to form a self-rewetting fluid. These self-rewetting fluids showed a unique behavior due to the inverse Marangoni effect. It was observed that the lower thermal resistance and higher heat transfer coefficient was obtained, especially in the dilute aqueous solution of 1-octanol.

**KEYWORDS**

PAPER SUBMITTED: 2020-05-09

PAPER REVISED: 1970-01-01

PAPER ACCEPTED: 2020-11-29

PUBLISHED ONLINE: 2021-01-02

**THERMAL SCIENCE** YEAR

**2021**, VOLUME

**25**, ISSUE

**Issue 1**, PAGES [781 - 790]

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