Melting of Phase Change Material Around a Heated Nanoparticle with Natural and Forced Convection
Master of Science
Phase change heat transfer has been an area of interest for decades due to its application in solar collectors, nuclear reactor cooling, buildings, vehicle engines, and others. Melting of phase change material around a spherical nanoparticle with natural and forced convection at its boundary is analyzed. The continuity, momentum, and energy equations describing melting of ice and fluid flow phenomena for water are solved using commercially available ANSYS FLUENT software. Variation of water properties within the nanoscale enclosure are considered. Aluminum nanoparticles embedded in phase change material resulted in faster heating when compared to silver, gold, and copper nanoparticles. The effect of natural convection on fluid flow and melting rate at the nanoscale is studied and multicellular flows are observed. The fluid flow and the melting pattern resulting from mixed convection are presented. The effect of forced convection, resulting from transport of nanoparticle due to an induced magnetic field and natural convection resulting from buoyancy forces are compared. In order to assess the validity of the numerical results, the well-known one-dimensional Stefan problem and the macroscale natural convection between two concentric spheres are studied as benchmarks.