Thermal–Hydraulic Performance Analysis and Optimization of a Recuperator via Geometric Modification Using Numerical Simulation and Artificial Neural Networks

• A novel ceramic plate internal recuperator with circular fins on the cold and hot sides is investigated. • HS identified as the dominant parameter, contributing up to 92.441% to heat transfer enhancement. • Optimal design enhances overall performance index by 154.5% compared to the finless configuration. • ANN model predicts Nu and ΔP with high accuracy (R 2 > 0.99) and strong generalization capability. • ANN–GA framework enables efficient identification of optimal designs for different conditions. Recuperators play a critical role in improving the thermal efficiency of turbine engines by recovering waste heat from exhaust gases and preheating the compressed air entering the combustion chamber. In this study, a novel layered ceramic plate recuperator incorporating circular fins within the flow passages is proposed and systematically investigated to enhance thermo-hydraulic performance. To obtain distinct configurations, three key geometric parameters related to fin arrangement, namely horizontal fin spacing, vertical fin spacing, and row pitch, are varied in the suitable geometrical ranges. Three-dimensional numerical simulations are performed to evaluate the Nusselt number, pressure drop, and an overall efficiency index selected as performance indicators. Also, the numerical model is validated against experimental data from a high-temperature ceramic plate heat exchanger. To achieve rapid and reliable performance prediction and optimization, an artificial neural network (ANN) was trained on a numerical dataset, exhibiting strong predictive performance, with coefficients of determination above 0.99 for both thermal and hydraulic characteristics. The trained ANN model is subsequently coupled with a genetic algorithm (GA) to perform single-objective and multi-objective optimizations. Multi-objective optimization using Pareto analysis and TOPSIS identifies designs offering balanced thermal enhancement and hydraulic penalty. The results demonstrate that an optimal fin configuration (OR1) yields a Nusselt number of 1335 and a pressure drop of 8506 Pa. In this design, the temperature of the compressed air increases from 382 K to 1091.3 K. The overall performance index of this recuperator is 2.545, indicating a 154.5% improvement in the overall performance compared with the finless recuperator.