Numerical simulation of grooved channel heat transfer enhancement: Structural optimization and pulsating flow

This paper investigates the heat transfer performance of a rectangular grooved channel heat exchanger under various conditions through numerical simulation, followed by structural optimization to develop a more efficient rectangular grooved heat exchanger. Geometric optimization of the rectangular grooved channel under steady-state flow conditions ( Re = 1200) was performed using Particle swarm optimization (PSO) and Bayesian optimization (BO) algorithm. Three parameters were optimized: groove starting point (x 2 ), groove depth (y 3 ), and groove ending point (x 4 ). The objective function was the performance evaluation criterion ( PEC s ). The optimized structure achieved a 2.9% improvement in the performance evaluation criterion compared to the pre-optimization design. Because the baseline is an already enhanced grooved geometry rather than a smooth duct, the observed improvement is relatively limited; the study’s main contribution is a transparent and transferable optimization methodology. The optimized rectangular groove is shallower, enabling more thorough fluid contact with the wall surface and facilitating heat transfer. When pulsating flow was applied to the optimized geometry, the PEC s reached its maximum value of 1.65 when the pulsation frequency matched the natural frequency. • Developed an automated closed-loop CAD–meshing–CFD–optimization workflow that supports multiple optimization algorithms, demonstrating the practicality and transferability of CFD-in-the-loop optimization for thermal design. • Proposed a synergistic enhancement strategy combining passive geometric optimization with natural-frequency pulsation.