Enhancing heat transfer with protrusion–rib structure on turbulent multiple-jet microchannel heatsink: an experimental and numerical study

This study investigates the synergistic effect of simultaneously integrated ribs and protrusions on the performance of multiple turbulent jets in a microchannel heat sink, using both experimental and numerical analyses. Ribs shield downstream jets from cross-flow, generate local turbulence and re-impingement to boost mixing. Meanwhile, protrusions increase the heat transfer area, disrupt the thermal boundary layer, and improve jet penetration. The Reynolds number ranges from 5000 to 8600 and the heat flux ranges from 149 to 287 W / c m 2 . Key thermal–hydraulic performance metrics, including heat transfer coefficient, Nusselt number, temperature uniformity, and pumping power, are evaluated. At Re = 7900, the experimental Nusselt number of 117 closely matches the simulation result of 120. At a heat flux of 287 W / c m 2 , the junction temperature remains at 42 °C which is well below the critical threshold of 65 °C. The obtained results suggest that the presented design can handle high heat fluxes up to 500 W / c m 2 while maintaining a safe junction temperature with single-phase flow. Overall, integrating rib-protrusion structures significantly improves temperature uniformity compared to previously reported designs.