Numerical Study of Cooling by Ferrofluids in an Electrical Transformer using an Axisymmetric Model

We present a numerical study of the cooling of a 40 kVA electrical transformer by using an oil-based ferrofluid. The temperature and velocity fields are compared to that obtained with regular transformer oil to assess the benefits of the ferrofluid. The interest of ferrofluids is in the thermomagnetic convection phenomenon generated by the leakage magnetic field. An axisymmetric model of the transformer shows that the ferrofluid reduces the maximum temperature.