Experimental investigation on the heat transfer performance of pulsating heat pipe with self-rewetting Fe3O4-nanofluid

Abstract

This paper conducted an experimental study on the heat transfer performance of pulsating heat pipe (PHP) under three different working fluids: ultrapure water, n-butanol self-rewetting fluid (SRWF), and self-rewetting Fe3O4-nanofluid (SRNF). The effects of filling ratio (FR), heating power, and magnetic field are studied. The results mainly show that the PHP with SRNF under a magnetic field, the start-up time increases, the evaporation section operating temperature increases, and the thermal performance decreases as the filling ratio increases. Increasing the FR, applying SRWF and SRNF can effectively increase the dry-out limit of PHP. At FR = 50 %, the overall thermal performance of PHP is best. In 10–130W, the thermal resistance of the SRWF and the SRNF with/without magnetic field is reduced by 14.5 %–27.8 %, 27.6 %–47.9 %, and 4.2 %–24.8 %, respectively, compared with that of ultrapure water. Similarly, compared without a magnetic field, the thermal resistance of SRNF with a magnetic field is reduced by 14.0 %–35.1 %. At FR = 50 %, the heat transfer performance of SRNF-PHP is best with a magnetic field. When the input power is 130W, the effective heat transfer coefficient keff is 5967.6 W/m∙ K, approximately 13.92 times greater than copper.