THERMAL SCIENCE

International Scientific Journal

Mengting Xiang

,

Feng Wang

,

Fei Dai

EXPERIMENTAL STUDY ON EVAPORATION OF DEFROSTING RESIDUAL DROPLET ON FIN SURFACE AND ENHANCEMENT BY ELECTRIC FIELD

ABSTRACT
In order to improve defrosting efficiency of air source heat pump, it is crucial to reveal the evaporation characteristics of defrosting residual droplet on fin surface and find ways to enhance the evaporation performance. In this work, the evaporation of defrosting residual droplet is investigated experimentally under different influence factors according to the defrosting condition of air source heat pump. Meanwhile, the availability of the evaporation performance enhanced by electric field is evaluated. Experimental results show that the droplet evaporates on superhydrophobic fin surface at constant contact angle and mixed modes, without the pinning stage; while it is constant contact diameter and mixed modes on bare fin surface. As the fin surface temperature increases or the droplet size decreases, the evaporation time of the droplet becomes shorter. The droplet evaporation time is 25.4% of that without electric field on bare fin surface, when the droplet volume is 1 L and the electric intensity is 15 kV/cm. Interestingly, the electric field forces the droplet on superhydrophobic fin surface to jump, and it is no longer necessary to remove the droplet by evaporation. In a word, applied electric field can enhance the droplet evaporation, which will save defrosting energy consumption and improve defrosting efficiency of air source heat pump.
KEYWORDS
Air source heat pump, defrosting residual droplet, evaporation, superhydrophobic surface, electric field
PAPER SUBMITTED: 2025-09-15
PAPER REVISED: 2025-10-15
PAPER ACCEPTED: 2025-10-16
PUBLISHED ONLINE: 2025-12-06
DOI REFERENCE: https://doi.org/10.2298/TSCI250915219X
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Experimental study on evaporation of defrosting residual droplet on fin surface and enhancement by electric field

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