Experimental Analysis of Rib Turbulator Configurations for Thermal Hydraulic Performance Enhancement in Gas Turbine Cooling Channels Operating at Extremely High Reynolds Numbers

Abstract This study offers a comprehensive experimental analysis of the thermal-hydraulic performance of six rib configurations, including Broken 30°, 45°, and 60° ribs, as well as Continuous 30°, 45°, and 60° ribs, tested at extremely high Reynolds numbers from 100,000 to 400,000. Experiments were conducted over a broad range of Reynolds numbers, representing conditions typical of both land-based and air-breathing gas turbine engines. Detailed heat-transfer measurements were performed under steady-state forced convection using Infrared Thermography (IR). The ribs tested are V-shaped, with a rib-height-to-hydraulic diameter ratio (e/Dh) of 1/20 and a rib pitch to rib height ratio (p/e) of 10. The results show that broken-rib configurations yield greater heat-transfer enhancement and improved thermal-hydraulic performance than traditional continuous ribs across the Reynolds number range studied. Additionally, broken ribs outperform their continuous counterparts by delivering greater heat transfer while reducing pressure losses. The study underscores that reducing rib height (e/Dh = 1/20) and using broken structures are effective strategies for achieving THP > 1 at very high Reynolds numbers, consistent with previous research. These insights provide a solid foundation for optimizing internal cooling passage designs in land-based and high-temperature gas turbines, thereby improving thermal efficiency and operational durability for next-generation turbine applications.