Enhancement of heat dissipation in panel-type radiators via fairing and axial induced fan

To augment the cooling performance of the vertical-blowing panel-type radiator used in transformer, this work introduces fairing and axial induced fan for structural improvement and airflow optimization of the radiator. Seven novel radiator cooling configurations were proposed and comparatively analyzed for air-side thermal performance. Optimal systems were selected for detailed oil cooling characterization, yielding a predictive temperature correlation. Finally, emergency cooling performance was evaluated across four fan arrangements. The research results indicated that the top induced draft configuration with fairing significantly improved heat transfer efficiency, with the total heat transfer rate increasing by approximately 14.00 % compared with the simple vertical blow. Elevating the total fan pressure and augmenting the oil flow rate are both effective strategies for improving the radiator's heat transfer performance. However, the oil-side thermal resistance was a secondary factor and had a limited impact on the total heat transfer rate. While increasing the oil flow velocity enhanced the total heat dissipation to a limited extent, it simultaneously reduced the inlet-to-outlet oil temperature gradient, resulting in higher outlet oil temperatures. Compared with the simple vertical blow, the top induced draft configuration with fairing reduced outlet oil temperature by up to 2.37 K. For optimal case, a multiple linear regression model was established to correlate the cooling degree of the insulating oil with relevant parameters, and the calculated values deviated from the simulation results by less than ±1.1 %. The emergency mode achieved a 12.51 % higher heat transfer rate than the simple bottom fan layout.