Effects of Curvature and Compound Angle on Cooling Performance and Flow Characteristics for a Combustor Liner With Tangential Effusion Cooling Configuration

Abstract

Abstract Tangential effusion cooling is considered as an efficient and advanced scheme for combustor liner cooling. Extensive research on tangential effusion cooling has been focused on the outer liner. However, the performance of tangential effusion cooling differs between the inner and outer liners due to their different wall curvatures. In this study, the tangential effusion cooling based on the outer liner and inner liner under the different blowing ratio and compound angle has been investigated numerically to evaluate the overall cooling effectiveness, flow characteristics and heat transfer coefficients. The result shows that the effusion cooling based on the outer liner exhibits superior cooling effectiveness, enhanced film coverage, and reduced heat transfer coefficients compared to that based on inner liner. The overall cooling effectiveness for effusion cooling based on outer liner is about 10% higher than that based on inner liner. The coolant jets attached the wall and flowing spiral forward in the outer liner based model, while the cooling film is detached from the wall and mixed with the mainstream in the inner liner based model. The increase of blowing ratio leads to a larger area-averaged heat transfer coefficient but improves convective heat transfer within effusion holes and enhances overall cooling effectiveness of the liner, particularly for outer combustor liner. The large compound angle has a negligible effect on the area-averaged overall cooling effectiveness but increases non-uniformity in overall cooling effectiveness distribution. This provides a reference and database for the cooling design for annular combustor liner with low cooling air consumption.