Optimization of fin surface wettability for promoting the dust removal in heat exchangers under frosting-defrosting conditions

• Published in: International journal of refrigeration Vol. 109; pp. 143 - 153
• Main Authors: Zhuang, Dawei, Yang, Yifei, Ding, Guoliang, Zhan, Feilong
• Format: Journal Article
• Language: English
• Published: Paris Elsevier Ltd 01.01.2020; Elsevier Science Ltd
• Subjects: Air conditioners; Air conditioning; Aluminum; Cleaning; Copper; Defrosting; Dust; Dust control; Dust removal; Dégivrage; Frosting; Givrage; Heat exchanger; Heat exchangers; Heat transfer; Hydrophilicity; Hydrophobic surfaces; Hydrophobicity; Metal plates; Mouillabilité de surface; Optimization; Surface wettability; Wettability; Échangeur de chaleur; Élimination de la poussière; Mouillabilité de surface; Dust removal; Échangeur de chaleur; Frosting; Heat exchanger; Élimination de la poussière; Surface wettability; Givrage; Defrosting; Dégivrage
• ISSN: 0140-7007; 1879-2081
• DOI: 10.1016/j.ijrefrig.2019.10.010

•The effect of wettability on dust removal by frosting-defrosting is investigated.•Dust removing rate on hydrophobic surface is higher than that on other samples.•Remnant dust weight on hydrophobic surface is far less than that on other samples.•Hydrophobic surface is identified as the optimal choice for promoting dust removal. Dust removal by frosting-defrosting is a novel way to keep the cleanness of heat exchangers of air conditioners during long-term operation, and the effect depends on the fin surface wettability. The purpose of this study is to obtain the optimal choice of fin surface wettability for dust removal by testing dust removal characteristics on various surfaces, covering bare aluminum surface, bare copper surface, hydrophilic surface and hydrophobic surface. The temperatures of the air dry-bulb, air wet-bulb, the frosting surface and the defrosting surface in the experiments are 7 °C, 6 °C, -15 °C and 5 °C, respectively. The results show that, the hydrophobic surface has the best dust removal effectiveness; the remnant dust rates on the surfaces are 28.4%, 28.0%, 8.69% and 0.54% for bare aluminum plate, bare copper plate, hydrophilic copper plate and hydrophobic copper plate, respectively; the dust removal time on hydrophobic surface is much less than that on the other ones.