Impact of Surfactants on the Electrical and Rheological Aspects of Silica Based Synthetic Ester Nanofluids

Abstract

This study reports experimental investigations of the effects of different surfactants (CTAB, Oleic acid and Span 80) on silica based synthetic ester nanofluids. The positive and negative potential observed for the ionic (CTAB) and non-ionic surfactant (Span 80) from zeta potential analysis indicates an improved stability. The optimization of nanofillers and surfactants is performed considering the corona inception voltage measured using ultra high frequency (UHF) technique and fluorescent fiber. Rheological analysis shows no significant variation of properties with shear rate, implying Newtonian behavior even with the addition of surfactant. In addition, the permittivity of the nanofluid is not much affected by adding surfactant but a marginal variation is noticed in the loss tangent with the effect of temperature. The fluorescence spectroscopy shows no change in the emission wavelength with the addition of silica nanofiller and surfactants. Flow electrification studies indicate an increase in the streaming current with the rotation speed and temperature, with a higher current magnitude observed in the case of nanofluids.

Understanding the Electro-Rheological Aspects of Nano Silica Based Ester Fluid With Surfactants and Deep Learning-Based Prediction of ECT

“…It is observed that CTAB, as a surfactant, exhibits excellent stability in comparison to the other surfactants, oleic acid and span-80. Similar observations of zeta potential are made with the silica based synthetic ester nanofluids [15]. CTAB being cationic surfactant carries positive charged head attach itself with the hydroxyl group.…”