ROLE OF NANOMATERIALS IN PHASE CHANGE MATERIALS

Abstract

Nano enhanced Phase change materials (NePCMs) is an innovative solution to enhance the performance of modern energy sources such as Thermal Energy Storage (TES), that has the capability to store and release energy upon demand. This approach is preferred over the inconsistent supplies of renewable energy, to resolve global energy consumptions challenges. Despite the inherent characteristics of high latent heat potential, PCMs have low thermal conductivity which squanders its potential performance. Numerical analysis with the use of computational fluid dynamics (CFD) simulations was employed to study the optimum conditions - orientation, morphology, materials and concentration, of nanomaterials that can enhance PCMs thermal conductivity performance in a shell and tube TES system. Results showed that vertical oriented cylinder is 2% and 12% more efficient than diagonal and horizontal cylinder, and PCM with higher aspect ratio 2-dimensional nanomaterial (nanosheets) being 47% and 51% more efficient than 1-dimension (nanotubes) and 0-dimension (nanoparticles) respectively. Additionally, copper-particle is 0.06% and 0.18% superior than Alumina-particle and carbon-particle respectively in a 1% volume concentration sample; and 0.4% better than pure PCM, in terms of thermal enhancement. The study added that percentage doping (5%, 3% and 1%) and the resulting enhancement levels (4%, 14% and 21%) are non-linearly related which is similarly reported in vast literatures. These results were generated with careful computations base on validated prediction models with experimental data and simulated with ANSYS FLUENT CFD software and serves to provide future research work with a comprehensive appraisal on the varying effects of the said factors.