THEORETICAL MODELLING OF THERMAL CONDUCTIVITY OF DEEP EUTECTIC SOLVENT BASED NANOFLUID

In this research, the thermal conductivities of graphene oxide nano-particles (GO) dispersed in deep eutectic solvents (DESs) composed of ethylene glycol (EG) as a hydrogen bond donor (HBD) and methyl tri-phenyl phosphonium bromide (MTPB) as a salt, at weight fractions of 0.01%, 0.02% and 0.05%, were studied and quantitatively analysed. The molar ratios of DES (HBD:Salt) used in this study are 3:1 and 5:1.The thermal conductivity data of the nano-fluid samples were measured at temperatures of 25-70 °C and the results were compared with theoretical models. Rashmi and Kumar’ models showed conflicting prediction performance. While, Rashmi’s model can predict thermal conductivity with error as low as 0.1%, Kumar’s model error varied from 3-55%. Thus, in this work, a simple empirical modification to Kumar’s model is presented which improves the predictions accuracy compared to that of Rashmi’s model.