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Title:Thermal and Flow Behaviour of Titania-Deionized Water Nanofluids Authors: Hajar Alias; Anwar Johari; Norzita Ngadi ; Muhd Zakwan Zaine DOI: Aff: Universiti Teknologi Malaysia, Chemical Engineering Department, Faculty of Chemical Engineering, 81310 UTM Skudai, Johor, Malaysia Author Email: Keywords: Nanofluids; Thermal Conductivity; Viscosity URLs:ABSTRACT-HTML | FULLTEXT-PDF | Abstract:In this research, the properties and characteristics of TiO2-Ethylene glycol nanofluids was investigated. The nanofluids was prepared using two-step method with the aid of Polyvinylpyrrolidone (PVP) as stabilizing agent. The effect of temperature and concentration on viscosity and thermal conductivity were studied. The different concentrations of nanofluids were tested over a temperature range of 30.C-60.C. The thermal conductivity was measured using thermal analyzer device that employes the hot-wire method. Thermal conductivity enhancement was observed for the nanofluids. It was also found that the surface chemistry (pH value) also affects thermopysical properties and rheological behaviour of nanofluids. The dynamic viscosity of nanofluids was measured using calibrated viscometer on cylindrical measurement chamber. The results showed that viscosity increases with increasing nanoparticles concentration. As temperature increases, the kinetic energy of nanoparticles will also increase and thus causes each nanoparticle to collide with higher frequency. This prevents the attraction forces between nanoparticles at the same time prevent agglomerations. The nanofluids showed shear thinning behavior.