Topology optimization of cold plates for enhanced heat transfer in battery packs: A comparative study of various optimized designs and impact of hybrid nanofluids as coolant

In this study. we propose a Topology Optimization approach for comparative analysis of five new battery cooling plate designs with conventional straight channel design, considering three different performance parameters: heat transfer, mean temperature, and power loss in fluid flow. A three-dimensional computational fluid dynamics model was established to compare the performance of the topology optimized designs under identical boundary conditions. Combining more than two objectives via multi-objective optimization model resulted enhanced heat transfer without causing elevated temperatures in the solid structure of the cold plate design. The results showed that the topology-optimized cold plate design obtained by prioritizing heat transfer reduced the maximum temperature by 1.246 [K], mean temperature by 1.709 [K], and pressure drop by 16.10%, with 4.24% increase in sensible heat transfer. Furthermore, the study examined the impact of coolants by comparing the performance of CNT-Al₂O₃ (0.1% w/w) hybrid water-based nanofluid and pure water based coolant in terms of decrease in temperature and percentage change in total sensible heat transferred to the coolant. The results show 2.459 [K] decrease in max temperature and 2.172 [K] reduction in mean temperature, with less than 2.19% reduction in heat transfer.