The thermal analysis of natural convection cooling type transformer

The life expectancy of the transformer largely depends on the temperature-rise in it. If the temperature-rise exceeds limits specified in the design standards, the aging of insulating materials is accelerated and also the capability of cooling medium is deteriorated. So, applicable limits of the temperature-rise is essential in designing transformer and coolers, demanding the estimation of the thermal behavior of transformer. In order to analyze the temperature characteristics of the transformer, the numerical analysis by using commercial CFD code has been carried out, and temperature-rise test to verify computed results was made. The results obtained in this study show that there is a good agreement between computed results and experimental one.