With the improvement of the speed, aerodynamic noises of trains also become more obvious. Reducing the aerodynamic noise has become a key factor to control noises of the high speed train. This paper uses large eddy simulation and boundary element method to compute the flow field and aerodynamic noises of pantographs and trains. The result presents that there are obvious eddies at the head, push rod, and base. Two obvious separation eddies can be found around the guide rod of the head and the push rod of pantographs. The front part of the base has a layer of shear flow, which leads to a separation eddy in the back of the base while the flow moves backward. Noises of pantographs mainly concentrate around the head, base and pushrod. With the increase of the analyzed frequency, the strength of pantograph noise source is weaker and weaker. When the analyzed frequency is 500 Hz, the noise source of pantographs is mainly around joints of several structures. By comparing the computational and the experimental result of aerodynamic noises of pantographs, this result presents that they are consistent with each other in the change tendency and value within the whole analyzed frequency. This indicates that the computational model of aerodynamic noises of pantographs is effective. Pantographs have an obvious influence on the distribution of the flow field around high speed trains, especially at the end of high speed trains. High speed trains with pantographs only have an eddy at the end, but high speed trains without pantographs have two eddies at the end. When this paper conducts on numerical computation for high speed trains, pantographs should not be ignored. In the low frequency, radiation noises of high speed trains can be found mainly around pantographs and at the end of trains. At the longitudinal symmetric plane of high speed trains, the sound pressure level at the end of trains is the highest. The radiation noise around pantographs mainly concentrates around the pushrod, then base, and the last is the head.

The force between wheels and rails of the high-speed train was firstly extracted and applied into the computational model of radiation noises of wheels and rail respectively. As a result, the radiation noise of wheels and rails was obtained. As can be seen from the result, radiation noises of wheels had an obvious directivity on the body surface, while radiation noises of rails had an obvious periodicity on the body surface. With the increase of the analyzed frequency, both directivity and periodicity were shown more obviously. Then the aerodynamic model of the high-speed train was established, and the pressure and velocity distributions on the train surface were computed. The maximum pressure was at the tip of the nose of the high-speed train, the maximum velocity was at the transition of the cabin, and more serious eddy was in the rear of the high speed train. Based on the computed pressure distribution, the aerodynamic noise was distributed evenly on the entire body surface, which was gradually increased with the increasing analyzed frequency. Finally, the wheel radiation noise, rail radiation noise and aerodynamic noise were extracted as excitations and applied into the SEA (Statistical Energy Analysis) model of the high-speed train, in order to compute its full-spectrum noise under multi-physics coupling excitations. The computational result was compared with the experimental result. It was presented that the difference of average sound pressure level (SPL) was 2.8 dB between the experimental and numerical simulations within the entire analytical frequency band. The SEA model with considering the multi-physics coupling was effective.