Topology Optimization of the Internal Flow Domain of a Transformer Pressure Relief Valve

Pressure relief valves (PRVs) are key safety components in power transformers, and their discharge performance directly influences pressure mitigation during internal fault events. This study presents a density-based topology optimization approach to improve the internal flow passage of a transformer PRV. Optimization is carried out within a predefined design domain while preserving the original external geometry and functional constraints of the valve. Pressure drop is defined as the objective function, and the Brinkman penalization method is used to model the fluid–solid transition during the optimization process. Based on the optimized topology, a reconstructed valve configuration is developed and evaluated using transient computational fluid dynamics (CFD) simulations. The transient inlet pressure boundary condition is obtained from a 6 MJ transformer arcing experiment to ensure realistic operating conditions. The hydraulic performance of the baseline and optimized designs is compared in terms of cumulative discharged volume, pressure field evolution, velocity distribution, and turbulent kinetic energy. The results indicate that the optimized flow passage reduces internal flow resistance and improves flow organization within the valve chamber under transient conditions. Over a 19 ms discharge period, the cumulative discharged volume increases from 13.219 L to 13.601 L, corresponding to an improvement of approximately 3%. These findings demonstrate that topology optimization can effectively enhance the transient discharge performance of transformer PRVs and provide a basis for improving internal flow design in similar hydraulic safety devices.