Optimization study on fluid flow and heat transfer in a rectangular channel with cross-scale ribs for turbine blade internal cooling.

This article focuses on optimizing the internal cooling performance of turbine engine blade channels by combining micro-ribs and macro-ribs in a cross-scale design. Using three-dimensional numerical simulations with the v2f turbulence model, the study evaluates how micro-ribs—specifically blade, triangular (sawtooth), and trapezoidal groove shapes—affect heat transfer and flow resistance when integrated with linearly decreasing height (LDH) macro-ribs. Results indicate that micro-ribs enhance near-wall flow velocity, reduce wall shear stress, and improve heat transfer without increasing pressure drop, with blade micro-ribs showing the greatest overall thermal performance improvement (up to 8.06% in combined heat transfer and friction factor metrics). The study concludes that this cross-scale rib design concept holds significant potential for advancing turbine blade cooling technologies, though practical challenges such as micro-rib material wear remain to be addressed in future research.