Study On Sound Insulation Performance Of High Speed Train Floor

The interior noise of high-speed trains seriously affects the comfort of passengers.The train floor is the main propagation path of interior noise.Research and analysis of the sound insulation performance of the vehicle floor is very important to reduce interior noise.This paper uses VA one software to establish a finite element-statistical energy hybrid sound insulation model in the middle and low frequency range of 20Hz-1000 Hz and applies the finite element method-statistical energy hybrid method.In the high-frequency range of1000Hz-5000 Hz,the statistical energy method is applied.Established a statistical energy sound insulation model,calculated and analyzed the full frequency sound insulation performance of the vehicle floor.The main contents of this article are as follows:(1)The sound insulation performance of the inner floor is calculated and analyzed.The finite element models of the composite inner floor and the aluminum honeycomb inner floor composed of wood and rubber are respectively established,and the mid-and low-frequency modes of the inner floor are calculated.Based on the inner floor mode,the finite element-statistics of the composite inner floor and the aluminum honeycomb inner floor are established.The energy mixing sound insulation calculation model is based on the basic principle of statistical energy.The high-frequency statistical energy sound insulation model of the composite inner floor and aluminum honeycomb inner floor is established,and the full frequency sound insulation performance of the composite inner floor and aluminum honeycomb inner floor structure is simulated and analyzed.The influence of the thickness of the wood layer and the thickness of the rubber layer on the sound insulation performance of the composite inner floor was analyzed and compared,and the influence of the thickness and density of the panel layer,the thickness and density of the aluminum honeycomb sandwich layer on the sound insulation performance of the aluminum honeycomb inner floor structure was analyzed.(2)Research on sound insulation performance of aluminum profile exterior floor.A finite element model of the aluminum profile outer floor was established,and the mid-low frequency mode of the aluminum profile was calculated.Based on the aluminum profile mode,the aluminum profile finite element-statistical energy hybrid sound insulation calculation model was established.Based on the basic principle of statistical energy,the aluminum The high-frequency statistical energy sound insulation model of the profile,simulation and analysis of the full frequency sound insulation performance of the aluminum profile structure.Analyzed and compared the influence of the thickness of the surface aluminum plate,the thickness of the ribs,the angle and the thickness of the cavity on the sound insulation performance of the aluminum profile,and analyzed the paving damping material,the thickness of the damping material,the properties of the damping material and the type of damping material on the sound insulation of the aluminum profile structure Performance impact.(3)Research on the sound insulation performance of the whole floor structure.Established a finite element model of the overall floor structure of "inner floor + air layer +damping material + aluminum profile",calculated the low frequency mode of the floor,based on the floor mode,established the overall floor finite element-statistical energy hybrid sound insulation calculation Based on the basic principle of statistical energy,a high-frequency statistical energy sound insulation model of the whole floor is established,and the sound insulation performance of the floor structure in the whole frequency range is simulated and calculated.The effects of the thickness,porosity and type of sound-absorbing material on the sound insulation performance of the overall floor structure are compared and analyzed.The research results show that the sound insulation performance of the aluminum honeycomb inner floor is better than that of the composite inner floor.Appropriately increasing the thickness of the panel layer of the aluminum honeycomb inner floor,the thickness of the wood layer and the thickness of the rubber layer of the composite inner wood floor can increase the sound insulation and increase the aluminum honeycomb clip.The thickness and density of the core layer have little effect on the sound insulation performance.Increasing the thickness of the surface aluminum plate,the thickness of the cavity and the thickness and density of the damping material can increase the sound insulation capacity.Decreasing the angle of the aluminum profile ribs can also increase the sound insulation.Increasing the thickness of the ribs has little effect on improving the sound insulation.Laying sound-absorbing materials can effectively increase the high-frequency sound insulation of the floor.Increasing the thickness and porosity of the sound-absorbing materials can increase the sound insulation.In the case of comprehensive consideration of quality and sound insulation,fiber mats are more suitable as sound-absorbing materials.