Effect of nanomaterials on the melting and solidification characteristics of phase change materials

Abstract

In the past few years, Phase Change Materials (PCMs) have received significant attention and are suggested as potential thermal energy storage (TES) media. The performance improvement of the TES system using PCM is attempted but is limited by its poor thermal conductivity, and attempts are seen to enhance this by adding high conductivity nanomaterials as an advanced heat transfer improvement technique. Although, these TES systems have considered as an important option in the modern era of energy research owing to their ability to store large amount of energy at constant temperatures with minimal changes in volume. In addition, nanotechnology is an effective way to enhance the thermal conductivity and time savings of the melting and solidification processes. Nanomaterials dispersed in the base PCMs are called composite PCMs. Composite PCMs have many advantages, such as high heat transfer rate, high thermal conductivity and improved thermal reliability and stability, etc. PCMs can be classified as organic, inorganic and eutectic. A wide range of fatty acid based PCMs are commonly available PCMs with high thermal energy storage density. Organic PCMs are primarily used for low and medium temperature applications, while inorganic PCMs can be used for applications at high temperatures. In the present research work, synthesis of nanomaterials (Al2O3, SiO2, CuO, Ag, ZnO, TiO2 and GO) were carried out in order to prepare the composite PCMs. As far as the present research work is concerned myristic acid, caprylic acid and lauric acid were reckoned as the base PCMs. The morphological structures of as-prepared nanomaterials were found by using field emission scanning electron microscopy (FESEM) and crystalline phases of them were characterized by means of x-ray diffraction (XRD). The two-step technique was adopted towards the preparation of composite PCMs. Sodium dodecylbenzene sulfonate (SDBS) was taken as the capping agent in order to ascertain the dispersion stability of the composite PCMs. In addition to this, sonica