Regarding the continuous development of high-speed trains and the increase of running speeds, the aerodynamic design of highspeed\ntrains has become significantly important, while reduction of drag and noise comprises a significant challenge in order to\noptimize aerodynamic design of high-speed trains. The design form factor of a high-speed train is highly influenced by\naerodynamic aspects including aerodynamic drag, lift force, and noise. With the high-speed train as the object, the paper aims\nto take bionic concept as the entry point, selecting the hummingbird as the bionic prototype and extracting bionic elements to\nestablish a bionic train model. Then, the finite volume method was used for numerical simulation and analysis of the\naerodynamic performance and aerodynamic noise of the bionic high-speed train. Computational results prove that drag and\nnoise of the bionic head type were lower than those of the original train; drag of the head train of the bionic model was reduced\nby 2.21% in comparison with the original model, while the whole-train drag was reduced by 3.53%, indicating that drag\nreduction effects are available and implying that the bionic head type could reduce drag and noise. Noise sources of the bionic\ntrain are mainly located at positions with easy airflow separation and violent turbulence motion. Large turbulence energy is in\nbogie areas and mainly exists at the leeward side of the bogie area. Obviously, the bogie area is the major noise source of the\ntrain. Aerodynamic noise of the bionic train in far-field comprises a wide-frequency range. Noises were concentrated within\n613 Hz~3150 Hz. When the bionic high-speed train ran at 350 km/h, through comparative analysis of total noise levels at\nobserved points of the high-speed train, it is found that this position with the maximum noise level was 25m away from the\nhead train nose tip, with the maximum value of 88.4 dB (A). When the bionic train ran at 600 km/h, the maximum sound\npressure level at the longitudinal point was 99.7 dB (A) and the average noise level was 96.6 dB (A). When the running speed\nincreased from 350 km/h to 600 km/h, the maximum noise level increased by 11.3 dB (A) and the average noise level increased\nby 11.6 dB (A). Computation results of aerodynamic noise at the point which is 7.5m away from the rail center show that the\nmaximum aerodynamic noise level existed at the first-end bogie of the head train, while the noise level was larger at the position\ncloser to the ground.
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