Study on Noise Reduction of High-speed Train Pantograph by Using Jet Device Based on Numerical Simulation and Wind Tunnel Test

Aiming at the problem of aerodynamic noise in pantograph area during the running of the high-speed train, a new active noise reduction method based on jet flow was proposed in this paper. Through the establishment of 1:30 scale jet model installed in the pantograph cavity in order to reduce the noise, the suppression effect of different jet velocities on aerodynamic noise from pantograph cavity was discussed. The influence of different jet velocities on turbulent kinetic energy, vorticity, surface sound power level and far field noise value was explored, using large eddy simulation and FW-H sound analogy method to solve the flow field and sound field in the pantograph cavity. The simulation results show that the optimal jet velocity is 40 m/s, when the Mach number is 0. 117. Under the optimal jet velocity, the maximum surface sound power level of pantograph cavity is reduced by 4. 503 dB, and the far field noise is reduced by 1. 43 dB and 1. 16 dB at 2. 5 m and 8. 333 m away respectively, which achieves the purpose of noise reduction. Based on the above results, the wind tunnel test about 1:30 scaled model of jet device was conducted and pulsating pressure data of monitoring points on the rear pantograph cavity wall were obtained and processed by using the Fourier transforms. Thus, noise spectral characteristics in the range of 300〜5 000 Hz were analyzed. The test results show that the total sound pressure level is reduced by 0. 53 dB and 0. 49 dB at middle and edge monitoring points on the rear wall respectively, under the velocity of 40 m/s. Compared with simulation results, the maximum error is 3. 54 dB, accounting for 2.4% of total sound pressure level, which demonstrates the accuracy and efficiency of the proposed method. © 2023 Science Press. All rights reserved.