Thermophysical investigation of a TiO2 embedded phase change material

TiO₂ nanoparticles were dispersed into a stearic acid to enhance the low thermal conductivity of this phase change material. The transient hot wire measurement technique showed an improvement of thermal conductivity by 43% in liquid state and 21% in solid state only by adding 0.3% of TiO₂ mass concentration. Prediction models of nanofluid´s thermal conductivity are found to be - unevenly - under predicting the obtained results. The rheological behavior of the prepared nanofluid is studied in a temperature range of 65°C-85°C. It is a shear thining nanofluid which becomes more viscous by adding nanoparticles or reducing temperature. The theoretical models gave good viscosity estimate. The Differential Scanning Calorimetry (DSC) shows an insignificant instability of the latent heat capacity in the case of 0.3% nanofluid mass concentration.