Nanograssed Micro‐V‐Groove Architectures for Continuous Dropwise Condensation and Droplet Directional Movement. Issue 16 (10th June 2018)

• Record Type: Journal Article
• Authors: Dong, Jian; Dong, He; Jin, Yanli; Sun, Li; Ye, Senbin
• Is Part Of: Advanced materials interfaces. Volume 5:Issue 16(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-06-10
• Subjects: droplet departure -- dropwise condensation -- nanograssed micro‐V‐groove architectures -- superhydrophobic surfaces; Materials science -- Periodicals; 620.11
• DOI: 10.1002/admi.201800202
• Languages: English
• ISSNs: 2196-7350

Abstract

Abstract: Engineering dropwise condensation on superhydrophobic surfaces (SHSs) has a wide range of applications from thermal management to water harvesting technologies. In this study, the hierarchical nanograssed micro‐V‐groove architectures are fabricated on copper surfaces for dropwise condensation and quick directional droplet departure. An optical microscope and a camera are adopted to investigate the spontaneous motions of condensate droplets on nanograssed micro‐V‐groove SHSs. The results show that the motions of condensate droplets on V‐groove slope surfaces appear quicker, more spontaneous, and more continuous, and reservoir droplets in V‐grooves appear more larger and more easy‐rolling. The phenomenon is explained by the critical radii of the rolling condensate droplets on V‐groove slope surfaces and maximum radii of the rolling reservoir droplets. In addition, water collection experiments are done, which shows that nanograssed V‐groove SHSs have better capacities of water collection than the nanograssed flat SHS. The smaller the V‐groove angle is, the better water collection capacity the SHS has. The synergistic cooperation between micro‐V‐grooves and nanograss contributes directly to the dropwise condensation process, which enhances vapor–liquid phase change efficiency. Exploiting such multiscale coupling effects can help us design optimal condensation surfaces for high performances of phase‐change cooling and water self‐catchment systems. Abstract : The hierarchical nanograssed micro‐V‐groove architectures are fabricated on copper surfaces for dropwise condensation and quick directional condensate droplet departure. The critical radii of the condensate droplet are used to explain the reason for different motions of condensate droplets. And, the maxium reservoir droplet radii are used to explain the reason for reservoir droplet drainage from the superhydrophobic surfaces.