Gold-in-Water Nanofluids in Microchannels: Surfactant Effect

2018-05-25
Şimşek, Eylül
Redmond, Matthew
Koyuncuoğlu, Aziz
Okutucu Özyurt, Hanife Tuba
Külah, Haluk
Heat transfer and pressure drop performance of gold-in-water nanofluids in microchannels are experimentallyinvestigated. Gold nanoparticles are suspended in de-ionized (DI) water. The nanofluid stability is maintained bypolyvinylpyrrolidone (PVP) for over 4 years. Nanofluids are tested in rectangular, MEMS produced coppermicrochannels of 70 μm x 50 μm cross-sectional area in a very low Reynolds number range of 30 < Re < 50.The performances of DI-water, PVP added DI-water, and gold-in-water nanofluid with added PVP arecompared. The nanofluids always yielded a higher heat transfer coefficients than PVP-DI water solution. Foroccasional combinations of the particle size, volumetric concentration and flow rate, gold nanofluids yieldedhigher heat transfer coefficients compared to DI water as well. The effects of flow rate and particle size on thefigure of merit (FM) are presented. The study is rare in dealing with pure metals (gold), and is important inemphasizing the surfactant effects on stable duration of nanofluids, and their thermal performance.
16th International Heat Transfer Conference (IHTC-16)

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Citation Formats
E. Şimşek, M. Redmond, A. Koyuncuoğlu, H. T. Okutucu Özyurt, and H. Külah, “Gold-in-Water Nanofluids in Microchannels: Surfactant Effect,” presented at the 16th International Heat Transfer Conference (IHTC-16), Beijing, Çin, 2018, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/79770.