CFD study of fluid flow and temperature distributions in a power transformer winding

The focus of the present numerical study is on the temperature distribution and the fluid flow of an oil cooled winding of a power transformer. The experimental setup consists of three passes of a zig-zag disc type winding, in which losses are modeled by heating cartridges in each winding segment. Precise temperature sensors measure the temperature of each turn. The laboratory setup allows the exact control of the boundary conditions, e.g. the oil flow rate and the inlet temperature. Furthermore, a simulation is carried out with a free open source computational fluid dynamics solver OpenFOAM and validated with the experimental results. The good agreement of the simulation results with experimental measurements validates the model. The model utilizes the turbulent flow for the different mass flow rates of the oil.