Lattice Boltzmann simulation of thermal investigation of natural convection in power transformer with nano-oil

The improvement of the thermal performance of transformer oil is essential due to the crucial role transformers perform in power distribution networks. Additionally, the electrical performance of a transformer is influenced by the temperature of its core. The natural convection heat transfer of a nano-oil sample, containing an Al۲O۳ nanoparticle in the base fluid of Paraffinic oil, has been studied theoretically and simulated by the lattice Boltzmann method and D۲Q۹ model in this paper, which presents a two-dimensional model of a transformer. For nanoparticle volume fractions of ۰% to ۵% and Rayleigh numbers of ۱۰۳ to ۱۰۵, modelling and solutions were carried out and, in this range, temperature charts and average Nusselt number are provided. In light of the findings of this study, adding nanoparticle to the base fluid has improved the cooling operation of the transformer core. Additionally, the natural convection heat transfer was enhanced by increasing the Rayleigh number and the volume fraction of nanoparticles. Paraffinic-Al۲O۳ nano-oil, at a volume fraction of ۵% and Rayleigh number of ۱۰۵, has the highest Nusselt number average of ۱۳.۰۷ and under the same conditions, the heat transfer has improved as compared to pure Paraffinic oil.

Keywords:

Heat transfer , Natural convection , Nanofluid , Transformer , Lattice Boltzmann method