| 摘要 |
Acoustic damping resonators (60, 62, 76, 78) formed in pockets (32) between reinforcing ribs (30) in a grid of ribs on the outer surface of a wall (74) surrounding a combustion gas flow path (18). Each resonator has a perforated cover plate (64A-C) spanning between sides formed by the ribs (30). Film cooling exit holes (44) are provided in the wall (74) under each resonator. Resonating chambers (48A-C) of different volumes may be provided on the wall to damp different unwanted frequencies. Different sets of resonators with different volumes may be separately controlled by respective airflow control manifolds (66) via throttle valves (68, T1-T3). Control logic (70) may control the valves based on frequency/airflow response functions (80, 82) for each size of resonator to optimize damping and cooling and to lower emissions over varying engine operating conditions. |
