Effect of coupled ribs and cavities on the hydrothermal comprehensive performance of microchannels under constant fluid domain volume

Rib-cavity coupled microchannels hold considerable promise for electronic device cooling, yet a universal design framework for rib-cavity coupling is still absent in the literature. To address this gap, the present work proposes a design strategy based on the principle of maintaining a constant fluid domain volume in microchannels. Numerical simulations are performed assess the feasibility of this strategy, covering five different microchannel configurations, MC, MC-SRCP, MC-PRCS, MC-SRCS, and DLMC-SRCS, over a Reynolds number ( Re ) range of 355-1065. Results show that rib-cavity coupling can significantly enhance hydrothermal comprehensive performance ( η ) without changing the fluid domain volume. Notably, DLMC-SRCS achieves an average η exceeding 1.8, with a peak of 1.847 at Re = 533, owing to combined improvements in wall impingement and interlayer fluid mixing, which represents a marked enhancement over previously reported results. This study provides a clear pathway for the structural optimization of microchannels in different application scenarios, thereby facilitating the transfer research experience and findings across various contexts.