Turbine noise would be one of the dominant noise sources especially in future UHBR (Ultra High Bypass-Ratio) aeroengine, but its currently far from being studied enough. Acoustic mode is crucial for duct propagation b...Turbine noise would be one of the dominant noise sources especially in future UHBR (Ultra High Bypass-Ratio) aeroengine, but its currently far from being studied enough. Acoustic mode is crucial for duct propagation but little study about the relation between serration and mode. Thus, taking axial single-turbine test bench NPU-Turb as object, the effect of Stator with Serrated Trailing-edge (Bionic S) and Rotor with Serrated Leading-edge (Bionic R) on duct acoustic modes of turbine turbulence interac-tion noise were studied in detail using DDES/AA hybrid model validated by acoustic experiment of NPU-Turb. Serval conclusions can be made here. First, for broadband noise, the effect of serrations on duct modes (increased or reduced of PWL<sub>mn</sub>) with the increasing frequency is more prominent. Second, the changing trend of ?PWL<sub>mn</sub> is something like Chinese character “人” with circumferential mode m and alternating with radial mode. Such distribution is more obvious at higher frequency. More theoretical and mechanistic research work needs to be carried out in depth in the future. .展开更多
文摘Turbine noise would be one of the dominant noise sources especially in future UHBR (Ultra High Bypass-Ratio) aeroengine, but its currently far from being studied enough. Acoustic mode is crucial for duct propagation but little study about the relation between serration and mode. Thus, taking axial single-turbine test bench NPU-Turb as object, the effect of Stator with Serrated Trailing-edge (Bionic S) and Rotor with Serrated Leading-edge (Bionic R) on duct acoustic modes of turbine turbulence interac-tion noise were studied in detail using DDES/AA hybrid model validated by acoustic experiment of NPU-Turb. Serval conclusions can be made here. First, for broadband noise, the effect of serrations on duct modes (increased or reduced of PWL<sub>mn</sub>) with the increasing frequency is more prominent. Second, the changing trend of ?PWL<sub>mn</sub> is something like Chinese character “人” with circumferential mode m and alternating with radial mode. Such distribution is more obvious at higher frequency. More theoretical and mechanistic research work needs to be carried out in depth in the future. .
