Topology optimization of the IWP triply periodic minimal surfaces (TPMS) heat sink based on porous media effective model

• Topology optimization of TPMS heat sink based on effective model is proposed. • The effective models adopt non-Darcy and local thermal equilibrium models. • The relationships between the effective parameters and density are established. • The heat transfer and flow performances of optimized TMPS heat sink are improved. To improve the performance of triply periodic minimal surfaces (TPMS) forced convection heat sinks, this study proposes an I-graph-wrapped package (IWP) TPMS topology optimization method based on a porous media effective model. The effective model establishes relationships between the porosity and effective parameters, simplifying flow and heat transfer calculations in the IWP-TPMS. The flow effective model adopts a non-Darcy model with key parameters, such as the Forchheimer coefficient and permeability, determined via the representative element volume and the Ergun equation. The thermal effective model is based on local thermal equilibrium, and the effective thermal conductivity is characterized by a series-parallel hybrid model. Topology optimization employs a density-based approach, treating IWP-TPMS structures with varying porosities as distinct materials, aiming to minimize the reciprocal of the performance evaluation criterion (PEC) for optimal overall performance. The proposed effective model is validated through case studies. The results show that the optimized IWP-TPMS reduces the peak temperature and pressure drop, with case 1 achieving reductions of 3.20% and 12.56%, respectively, and case 2 achieving reductions of 11.66% and 39.13%. These results highlight the effectiveness of combining a porous media effective model with topology optimization for optimization design of TPMS heat sinks.