Transport properties of nano manganese ferrite–propylene glycol dispersion (nanofluids): new observations and discussion

• Published in: Journal of nanoparticle research : an interdisciplinary forum for nanoscale science and technology 2013-07, Vol.15 (7), p.1-14, Article 1774
• Main Authors: Aishwarya, V., Suganthi, K. S., Rajan, K. S.
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Flows in ducts, channels, nozzles, and conduits; Fluid dynamics; Fundamental areas of phenomenology (including applications); Glycols; Heat transfer; Inorganic Chemistry; Lasers; Manganese; Materials Science; Nanocomposites; Nanocrystalline materials; Nanofluids; Nanomaterials; Nanoparticles; Nanoscale materials and structures: fabrication and characterization; Nanostructure; Nanotechnology; Optical Devices; Optics; Photonics; Physical Chemistry; Physics; Research Paper; Sulfates; Thermal conductivity; Thermal properties of condensed matter; Thermal properties of small particles, nanocrystals, nanotubes; Viscosity
• ISSN: 1388-0764; 1572-896X
• DOI: 10.1007/s11051-013-1774-3

Experiments were conducted on the preparation of manganese ferrite nanoparticles and their surface modification for dispersion in propylene glycol. The appropriate concentrations of ferrous sulphate and manganese sulphate (precursors) for synthesis of uniform Mn 0.43 Fe 2.57 O 4 nanoparticles (size range ~20–25 nm) were found to be 0.05 and 0.025 M, respectively. These nanoparticles were coated with citric acid and dispersed in propylene glycol for the preparation of nanofluids. The effects of temperature and nanoparticle concentration on nanofluid viscosity and thermal conductivity have been studied. Our study on the influence of nanoparticle concentration on viscosity reveals the existence of a viscosity minimum for 0.25 vol% of citric acid-modified Mn 0.43 Fe 2.57 O 4 –propylene glycol nanofluid. A thermal conductivity enhancement of 68 % was observed for 2 vol% nanofluid. Correlating viscosity and thermal conductivity measurements, particle clustering seems to be the major factor responsible for thermal conductivity enhancement.