Comparative study of aeroacoustic performance of 1/8 and 1/1 pantographs coupled with cavity  

作　　者：Xiaoming Tan Huifang Liu Zhigang Yang Hong Chen Baojun Fu Linli Gong 

机构地区：[1]Key Laboratory of Intelligent Manufacturing and Service Performance Optimization of Laser and Grinding in Mechanical Industry,Hunan Institute of Science and Technology,Yueyang 414006,China [2]Department of Civil and Environmental Engineering,The Hong Kong Polytechnic University,Hong Kong,China [3]Key Laboratory of Traffic Safety On Track,Ministry of Education,Central South University,Changsha 410075,China [4]The State Key Laboratory of Heavy-Duty and Express High-Power Electric Locomotive,CRRC Zhuzhou Locomotive Co.,Ltd,Zhuzhou 412001,China

出　　处：《Railway Engineering Science》2024年第4期551-572,共22页铁道工程科学（英文版）

基　　金：supported by the National Natural Science Foundation of China (No. 52272363);the Key Laboratory of Aerodynamic Noise Control (No. ANCL20200302),Aid Program for Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Province。

摘　　要：The technology of pantograph sinking in the cavity is generally adopted in the new generation of high-speed trains in China for aerodynamic noise reduction in this region. This study takes a high-speed train with a 4-car formation and a pantograph as the research object and compares the aerodynamic acoustic performance of two scale models, 1/8 and 1/1, using large eddy simulation and Ffowcs Williams–Hawkings integral equation. It is found that there is no direct scale similarity between their aeroacoustic performance. The 1/1 model airflow is separated at the leading edge of the panhead and reattached to the panhead, and its vortex shedding Strouhal number(St) is 0.17. However, the 1/8 model airflow is separated directly at the leading edge of the panhead, and its St is 0.13. The cavity's vortex shedding frequency is in agreement with that calculated by the Rooster empirical formula. The two scale models exhibit some similar characteristics in distribution of sound source energy, but the energy distribution of the 1/8 model is more concentrated in the middle and lower regions. The contribution rates of their middle and lower regions to the radiated noise in the two models are 27.3% and 87.2%, respectively. The peak frequencies of the radiated noise from the 1/1 model are 307 and 571 Hz. The 307 Hz is consistent with the frequency of panhead vortex shedding, and the 571 Hz is more likely to be the result of the superposition of various components. In contrast, the peak frequencies of the radiated noise from the 1/8 scale model are 280 and 1970 Hz. The 280 Hz comes from the shear layer oscillation between the cavity and the bottom frame, and the 1970 Hz is close to the frequency at which the panhead vortex sheds. This shows that the scaled model results need to be corrected before applying to the full-scale model.

关 键 词：Pantograph cavity coupling Aerodynamic noise Scale effect Large eddy simulation 

分 类 号：U264.34[机械工程—车辆工程]