Numerical simulation of aerodynamic noise and noise reduction of high-speed train connection section

Aerodynamic noise of high-speed train connection section with different parameters were simulated numerically adopting LES model companied with acoustic analogy and reducion improvement project was proposed.The aerodynamic noise distribution of high-speed train connection section at speed of 300km/h was obtained from the research,the results show that aerodynamic noise is a kind of wide frequency noise which exits in wide frequency band.The acoustic pressure amplitude of every test point is bigger at low frequency,increasing firstly then decreasing with the increase of frequency,and acoustic pressure level within 1/3 octave band frequency concentrates in the rage of 315-1000Hz;Among different parameters of train connection section,the acoustic pressure level amplitude increases with the increase of groove length and height;Compared with the project without windshield,the noise reduction effect of full windshield project is apparent,avoiding severe disturbance flow effectively,the average acoustic pressure level reductive amplitude is 9.4% and the average total acoustic pressure level reductive amplitude is 4.27dBA.All these researches provide scientific foundation to the initial design of high-speed train with low noise.