Study On Carbon Fiber Composite Pantograph Shroud Of High-Speed Trains Based On Reducing Noise

When a train runs at high speed, the noise includes the mechanical noise produced by the train itself and the noise generated by air friction. By analysis, when the traveling speed of the train reaches300km/h. the aerodynamic noise generated by air friction will be greater than the wheel-rail noise and the aerodynamic noise will become the major noise of the train. The noise on the train’s roof which is mainly generated by the pantograph increases by the six power of the vehicle speed. Therefore, how to reduce the noise generated by the pantograph effectively is the problem that we should focus on to solve.In this paper, the shroud of Chinese patent (called the shroud structure A) is optimized in order to further reduce the existing noise of the pantograph. Through researching the papers on the way of how to reduce the road noise, it is found that changing the shape of the road sound barrier’s head can reduce the road noise more, and if the shape of the head is changed to L-shaped, the effect will be better. So. in this paper the head shape of shroud structure A is attempted to change to L-shaped, and the result is that the noise caused by the changed shroud structure is lower than before. Considering the vehicle boundary, the central structure of the L-shaped shroud head is changed to tilt, and then further optimization is given to the structure based on the static strength calculation results so that the final structure is determined to be the shroud structure CCurrently carbon fiber reinforced composite(CFRP)is one of the most advanced composite materials and CFRP is widely used as structural materials because of its high temperature resistance, corrosion resistance, excellent thermodynamic properties. lightweight, high strength, and many other advantages that the other fiber reinforced composites do not have. Therefore, there is great application prospect to use CFRP layer design in body parts,which makes the best use of the composite material’s advantages, such as light weight, high strength, functional designability, high specific strength,high specific stiffness and many other advantages. In this paper, the mechanical characteristics of CFRP and the basic theories are correlatively expounded, and a reasonable layer structure which is designed instead of the traditional steel structure is used as the shroud structure C’s material in calculation. In the entire shroud structural design process, the layer design is used and the calculation results are checked by the relevant standards in order to carry out the structural optimization design.The study of this paper shows that the newly-designed shroud structure C, which is plied with the carbon fiber composite, can reduce the pantograph noise more effectively.The weight of the new structure is only two thirds as much as before and its strength is in compliance with relevant standards for carbon fiber composite material.