Aerodynamic noise calculation and shape optimization of high-speed train pantograph insulators

By using large eddy simulation and FW-H equation,the aerodynamic noises radiated from pantograph insulators were calculated,including rectangular,circular,oval-shaped cross-section insulators,the optimized cross-section shape was confirmed.The results show that in the same model,the sound pressure level(SPL) distribution at each sound receiver point from different sound receivers is basically the same,but the amplitude is reduced with the increase of distance from insulators.In different models,the SPL distribution is different at each frequency point.From rectangular,circular to oval shaped cross-section model,the freguency of the maxmium SPL gradually reduces.For reducing aerodynamic noise,the oval section insulator is optimal,and the long oval axis should be consistent with the air flow.The pantograph with bigger parts size and less parts number is helpful to reduce the aerodynamic noise.