Numerical and experimental performance investigation of a heat exchanger designed using topologically optimized fins

Abstract

Topology optimization for thermal-fluid problems has been successfully used to improve performance of small structures used for heat transfer. Optimization of full heat exchangers, due to analysis method limitations and computational costs, has not been able to produce manufacturable designs complex enough to satisfy heat exchanger specifications. The goal of this study is determining if a practical heat exchanger design can be obtained by the use of topology optimization. By considering a plate-fin heat exchanger, topology optimization is used to obtain a locally optimized fin pattern which is extended to form a heat exchanger core. A modification of the Number of transfer units method is presented to deal with the unique topology obtained by optimization and evaluate the performance of the exchanger. The performance, when compared to traditional serrated fin designs, show that optimization improvements extend beyond the optimized region onto the entire exchanger. The results show that the optimized design is an improvement outside optimization flow parameters. However, the limitations in 3D printer technology result in slight deviation of experiment results compared to the analysis, and prevent the manufacturing of designs with comparable total performance values to heat exchangers manufactured through traditional methods. • Design procedure obtains a heat exchanger core by localized topology optimization. • NTU method is modified to evaluate results of topology optimization. • Modified NTU, CFD and experimental evaluations are in good agreement with each other. • Performance improvements are maintained outside optimization flow parameters.