Experimental investigation of thermal conductivity and stability of TiO2-Ag/water nanocompositefluid with SDBS and SDS surfactants

Abstract In recent times, addition of two nanoparticles in base fluid called hybrid (or) nanocompositefluid is the subject of research in the area of nanofluid. In general, stability of single or composite nanoparticles in base fluid is the key issue that restricts the practical applications of nanofluids. In this paper, stability of TiO 2 -Ag/water nanocompositefluid with and without the addition of common surfactants like sodium dodecyl sulfate (SDS) and sodium dodecyl benzene sulfonate (SDBS) in different weight fractions (0.1, 0.3, 0.5, and 0.7 wt.%) is investigated. Thermal conductivity of water is increased by 12.2% by the addition of TiO 2 -Ag nanocomposite particle (≈ 9:1). It is found that addition of surfactant alters the enhancement in thermal conductivity of TiO 2 -Ag/water i.e. 29.6 % for 0.1 wt.% SDS and 2.1 % for 0.1 wt.% SDBS. The zeta potential is measured as -50.7 mV for 0.1 wt.% SDBS and -26.2 mV for 0.1 wt.% SDS which confirms good stability.