Rheological and volumetric properties of TiO2-ethylene glycol nanofluids
Departamento de Física Aplicada, Facultade de Ciencias, Universidade de Vigo, Vigo 36310, Spain
Nanoscale Research Letters 2013, 8:286 doi:10.1186/1556-276X-8-286Published: 13 June 2013
Homogeneous stable suspensions obtained by dispersing dry TiO2 nanoparticles in pure ethylene glycol were prepared and studied. Two types of nanocrystalline structure were analyzed, namely anatase and rutile phases, which have been characterized by scanning electron microscopy. The rheological behavior was determined for both nanofluids at nanoparticle mass concentrations up to 25%, including flow curves and frequency-dependent storage and loss moduli, using a cone-plate rotational rheometer. The effect of temperature over these flow curve tests at the highest concentration was also analyzed from 283.15 to 323.15 K. Furthermore, the influence of temperature, pressure, nanocrystalline structure, and concentration on the volumetric properties, including densities and isobaric thermal expansivities, were also analyzed.