Bio-inspired dendritic ribs for enhanced heat transfer and reduced flow resistance in cooling channels of turbine blades

This study introduces a bio-inspired dendritic rib design, developed through CFD simulations ( v 2 f turbulence model, 6.8% deviation from experiments) in a rectangular ribbed channel across Reynolds numbers 20,000–80,000. The simulations were conducted in a rectangular channel with an aspect ratio of 2:1, which featured six rib configurations and used a 5.3 million-cell mesh. This mesh was validated by grid independence tests, which showed less than 1.0% variation in Nu / Nu 0 and f / f 0 . The underlying mechanisms of the dendritic ribs are attributed to the generation of symmetric secondary vortices that intensify fluid mixing, the development of extended reattachment zones leading to a 10.40% to 25.23% increase in Nu / Nu 0 compared with transverse ribs, and the mitigation of friction losses with a 5.19% to 16.45% decrease in f / f 0 owing to optimized flow guidance. Among the tested configurations, the 30° dendritic rib achieves the best overall balance between heat transfer augmentation and pressure drop, yielding improvements of 49.9% and 32.97% in performance evaluation factors OPT 1 and OPT 2 . Therefore, the results showed that a rib angle of α = 30° with a branch level of n = 1 was optimal for the biomimetic dendritic rib channels. • Biomimetic dendritic ribs increase convective heat transfer by 25.23% while reducing flow loss by 16.45%. • The rib arrangement exhibits optimal thermal–hydraulic balance. • A 30° rib angle with branch level 1 achieves optimal thermal–fluid performance.