Regulating Droplet Dynamic Wetting Behaviors Using Surfactant Additives on High‐Temperature Surfaces. Issue 14 (1st June 2020)

• Record Type: Journal Article
• Authors: Zhang, Peipei; Peng, Baoxu; Yang, Xiaoxiao; Wang, Jingming; Jiang, Lei
• Is Part Of: Advanced materials interfaces. Volume 7:Issue 14(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-06-01
• Subjects: bubble nucleation -- droplet dynamic behavior -- high‐temperature -- Leidenfrost -- surfactant; Materials science -- Periodicals; 620.11
• DOI: 10.1002/admi.202000501
• Languages: English
• ISSNs: 2196-7350

Abstract

Abstract: Impacting the behavior of surfactant droplets impinging upon a heated surface is an intriguing research topic, and is important in spraying cooling processes. Surfactant additives significantly increase nucleate boiling heat transfer by promoting vapor bubble nucleation and foaming. However, it is still not exactly clear how surfactants influence the droplet dynamic behaviors at the heated interfaces, nor is the relationship between the droplet dynamic behaviors and heat transfer performance. Here, three familiar surfactant molecules, i.e., anionic surfactant molecule sodium dodecyl sulfate (SDS), cationic surfactant molecule hexadecylcetyltrimethylammonium bromide (CTAB), and nonionic surfactant molecule poly(ethylene glycol) 1000 (PEG‐1000), are chosen to investigate the dynamic behaviors of the water droplets with surfactant additives on the heated smooth surface with different chemical components. At low temperatures, surfactant‐enhanced spreading of droplets on the hydrophilic and hydrophobic surfaces is achieved due to the surfactant adsorption. At high temperature, bubble jet and bubble explosion processes on the hydrophilic surfaces can generate plenty of bubbles, the bubbles flee away the heated surface and the heat transfer efficiency greatly is improved. SDS and CTAB significantly reduce the Leidenfrost point (LFP) on the hydrophilic and hydrophobic surfaces. PEG‐1000 increases the LFP, which is little affected by variation of concentration. Abstract : Surfactant additives can regulate dynamic behaviors of the water droplets on heated smooth surfaces with different chemical components. Ionic surfactants (SDS and CTAB) significantly reduce the Leidenfrost point (LFP) on the hydrophilic and hydrophobic surfaces. While, nonionic surfactant increases the LFP, which is little affected by variation of PEG‐1000 concentration.