ABSTRACT
This chapter presents a thermal model of an oil cooled power transformer, along with details of computer implementation and experimental verification. It expresses that the oil flow through the disk coils is guided by oil-flow washers. The chapter also discusses oil flow through vertical ducts. It is assumed that the disk coil to be subdivided into directed oil flow cooling paths. Along a given path, the oil velocities are uniform since the cross-sectional area is assumed to remain constant. The disk temperatures can be found by equating the I2R losses to the heat passing through the disk surface in the steady state. The radiators modeled are fairly typical in that they consist of a series of vertical plates containing narrow oil channels. Tank cooling occurs by means of natural convection and radiation. Computer codes were written to perform steady-state, transient, and pumped oil-flow calculations.
