Research Progress on Film Cooling Fed by Crossflow Ribbed Passage of Gas Turbine Blades

Abstract

ObjectivesThe inlet temperature of gas turbine has far exceeded the allowable temperature of the blade material, so it is very important to develop more efficient turbine cooling technology, especially the film cooling technology. The film cooling in the central region of the turbine blade is usually supplied by the crossflow ribbed passage. Therefore, the research progress of the film cooling in the crossflow ribbed passage in recent years was reviewed.MethodsThe variations in film cooling performance under different coolant supply modes were introduced. The impacts of rib angle, rib shape, relative position of film holes and ribs, and Reynolds number at the inlet of the crossflow channel on flow and film cooling performance were summarized. The research progress of film cooling hole shape design under the condition of crossflow ribbed cooling air was concluded.ResultsThe internal cooling structures within the crossflow ribbed passage and the Reynolds number at the entrance of the crossflow channel exert significant influences on film cooling performance, while the distribution of cooling effectiveness at the hole outlet downstream is altered during crossflow intake. Moreover, the flow at the hole entrance is influenced by both the relative position of the hole and rib as well as changes in Reynolds number. The asymmetrical spanwise cooling hole and the hole insensitive to the crossflow can enhance the film cooling performance.ConclusionsIn order to further promote the development of film cooling technology in the crossflow ribbed passage, it is recommended to thoroughly study the relationship between film cooling performance and all influencing factors, and to optimize the design of special film cooling hole suitable for crossflow ribbed inlet.

Keywords

• gas turbine
• film cooling
• turbine cooling
• ribbed passage
• turbine blade
• rib
• blade cooling
• cooling efficiency