Baydaa Jaber Nabhan - Department of Mechanical Engineering, College of Engineering, AL-Mustansiriya University

To optimize the utilization of thermal conversion systems, it is essential to integrate them with thermal energy storage. Among many types of base materials, the phase change materials (PCMs) are the most satisfactorymediums to store and release the thermal energy due to their high latent heat of fusion. In general, the (PCMs) have low thermal conductivity. Nano additives have been investigated to further enhance the thermal properties ofthe (PCMs). In this study, the thermal conductivity of paraffin wax has been enhanced by adding different mass concentration (1wt. %, 3wt. %, 5wt. %) of (TiO2) nanoparticles with about (10nm) diameter. It is found that thephase change temperature varies with adding (TiO2) nanoparticles in to the paraffin wax. The thermal conductivity of the composites is found todecrease with increasing temperature. The increase in thermal conductivityhas been found to increase by about (10%) and (7%) by using spherical and trapezoidal capsules respectively at nanoparticles loading (5wt. % and 15oC).

Phase change materials (PCM), Thermal conductivity, TiO2