Abstract
Film cooling technology provides efficient thermal protection and maintains its effectiveness even in supersonic flow conditions. However, the interaction between the film cooling jets and the mainstream generates counter-rotating vortex pairs. This vortex pairs will carry coolant away from the wall and promote mixing with the mainstream, thereby reducing the efficiency of film cooling. Consequently, this paper introduces a new combination scheme that combines film cooling with “herringbone” riblets. The “herringbone” riblets are a bionic structure inspired by the microstructures found in shark skin and bird feathers. This structure creates a pair of vortices, which effectively control the flow field. This paper presents a detailed analysis using the RANS method with the SST k-ω model. Additionally, the influence of the riblets' positioning on the flow characteristics and the cooling performance of film cooling is investigated. The research results indicate that “herringbone” riblets can effectively suppress counter-rotating vortex pairs and strengthen Anti-counter-rotating vortex pairs. This action prevents the coolant from detaching from the wall and enhances the coolant's transport efficiency in the spanwise direction. As a result, “herringbone” riblets arranged upstream of the jet holes can improve the average cooling efficiency by 17.39%, whereas those situated downstream can improve it by 26.08%. The use of “herringbone” riblets also significantly enhances the minimum cooling efficiency in the downstream region of the jet holes. This study explains how “herringbone” riblets improve film cooling performance and provides a foundation for applying bionic structures in supersonic film cooling.
Original language | English |
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Article number | 110367 |
Journal | Aerospace Science and Technology |
Volume | 165 |
DOIs | |
State | Published - Oct 2025 |
Keywords
- Bionic structure
- Cooling effectiveness
- Film cooling
- Numerical simulation
- Supersonic flow