ANALYSIS OF THE THERMAL STATE AND CHARACTERISTICS OF THE COOLING OIL FLOW OF POWER TRANSFORMERS
Problem. The need to determine the temperature levels of the most heated winding points as the most important factor in ensuring the reliability and durability of transformer equipment (Fig. a). Engineering calculation methods do not fully take into account the real physical effects, the impact of which can only be assessed by modeling the flow and heat transfer processes in the transformer.
Suggestion for solving the problem. Development and application of more accurate CFD models (Fig. b) for the analysis of hydrodynamic and temperature fields in reels and cooling channels of transformer winding fragments with a natural cooling system. The results established that the flow of the cooling oil is of a complex non-uniform nature and depends on the totality of the regime and design parameters of the system.
The developed CFD models made it possible to determine not only the temperature value of the most heated points of the windings, but also their localization.
Work was carried out for:
- National Academy of Sciences of Ukraine – Development and use of three-dimensional models in a conjugate formulation for the analysis and optimization of transformer cooling systems.
- NAS of Ukraine – Research of hydrodynamics and heat transfer of viscous liquids in minichannels of cooling systems of power transformers.
- Zaporizhtransformator – development of a method for numerical simulation of heating of coil windings of oil transformers.