1. The contact angle of nanofluids as thermophysical property
- Author
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N. Garmendia, M.-R. Kalus, Raúl Martínez-Cuenca, K.-G. Schroth, Alfredo Amigo, Luca Doretti, Patrice Estellé, Vicente Alonso, M. Lasheras-Zubiate, Simona Barison, Angel Huminic, M. Hernaiz, A. Kujawska, Alpaslan Turgut, Ziya Haktan Karadeniz, Nur Çobanoğlu, Zan Wu, L. Hernández López, Matthias H. Buschmann, Rosa Mondragón, Bengt Sundén, Simone Mancin, Gabriela Huminic, European Union through the European Regional Development Fund (ERDF), Frenche Ministry of Higher Education and Research (France), French region of Brittany, Rennes Métropole, Laboratoire de Génie Civil et Génie Mécanique (LGCGM), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), COSTCOST (European Cooperation in Science and Technology), 49VF 170005, Bundesministerium für Wirtschaft und EnergieBundesministerium für Wirtschaft und Energie (Germany), ERDFERDF, ENE2017-86425-C2-2-R, Spanish Ministry of Economy and Competitiveness and the UE FEDER programme, Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)
- Subjects
Influence of temperature ,Materials science ,Round robin test,Contact angle, Nanofluids,Influence of volume,Influence of temperature,Experimental strategy ,Round robin test ,Oxide ,02 engineering and technology ,Substrate (electronics) ,010402 general chemistry ,01 natural sciences ,[SPI.MAT]Engineering Sciences [physics]/Materials ,law.invention ,Biomaterials ,Atmosphere ,Surface tension ,Contact angle ,Nanofluids ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,Nanofluid ,law ,[PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph] ,[SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics ,Composite material ,contact angle ,influence of volume ,round robin test ,nanofluids ,Graphene ,experimental strategy ,[SPI.FLUID]Engineering Sciences [physics]/Reactive fluid environment ,Experimental strategy ,021001 nanoscience & nanotechnology ,Influence of volume ,influence of temperature ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Volume (thermodynamics) ,chemistry ,[PHYS.MECA.THER]Physics [physics]/Mechanics [physics]/Thermics [physics.class-ph] ,0210 nano-technology - Abstract
International audience; Droplet volume and temperature affect contact angle significantly. Phase change heat transfer processes of nanofluids – suspensions containing nanometre-sized particles – can only be modelled properly by understanding these effects. The approach proposed here considers the limiting contact angle of a droplet asymptotically approaching zero-volume as a thermophysical property to characterise nanofluids positioned on a certain substrate under a certain atmosphere.Graphene oxide, alumina, and gold nanoparticles are suspended in deionised water. Within the framework of a round robin test carried out by nine independent European institutes the contact angle of these suspensions on a stainless steel solid substrate is measured with high accuracy. No dependence of nanofluids contact angle of sessile droplets on the measurement device is found. However, the measurements reveal clear differences of the contact angle of nanofluids compared to the pure base fluid.Physically founded correlations of the contact angle in dependency of droplet temperature and volume are obtained from the data. Extrapolating these functions to zero droplet volume delivers the searched limiting contact angle depending only on the temperature. It is for the first time, that this specific parameter, is understood as a characteristic material property of nanofluid droplets placed on a certain substrate under a certain atmosphere. Together with the surface tension it provides the foundation of proper modelling phase change heat transfer processes of nanofluids.
- Published
- 2019