Numerical analysis of the impact of fin design and solar radiation on the cooling performance of a power transformer

In the present work, a three-dimensional model was performed to test a geometry and solar radiation effect on the cooling efficiency of a 250 kilovolt-ampere (kVA) oil-natural-air-natural (ONAN) electrical distribution transformer. Several fin shapes and other geometric aspects of the transformer were analyzed numerically (trapezoidal, wavy, and triangle fins).According to the findings, the trapezoidal fin shapes were the most effective in lowering the transformer's average surface and core temperatures, followed by the wavy fins and the triangular fins compared to the traditional transformer shape (straight fins). The study also showed that the temperature of the surface and the core of the transformer increases with increasing solar radiation, but the effect of high temperature as a result of electrical load is more influential than solar radiation. The results showed a significant convergence with previous research.