The Study On Equivalent Model Of Hollow Aluminum Extrusion

The noise and vibration of high speed railway transportation is a very straightforward question, with the speed of the train increasing. In the simulation technology, to improve the simulation accuracy of high-speed train noise and vibration can provide effective protection for the design of new high-speed train. However, EMU body panels are mostly hollow extruded aluminum. If the finite element method is adopted completely, simulation analysis will produce a large number of grid and increase the difficulty of computing and extend the design cycle. Therefore, it needs to study the equivalent plate model of hollow extruded aluminum to establish a mixed model of SEA plates and FE plates for simulation analysis.Based on the relationship of structural vibration, sound radiation and sound insulation, this paper derives new theoretical equivalent of vibration mode. This paper The EMU-floor specimens was selected for the study. And the new theoretical research was adopted to study equivalent homogeneous single floor plate model. Firstly, the free modal and transmission loss of the floor specimen were carried out by experimental tests and simulation. Through comparative analysis of experimental data and simulation data, it was proved that the simulation calculation was reliable. Secondly, with the usage of the simulation data of the EMU-floor, the equivalent theory, matlab procedures and genetic algorithm, the attribute parameters of equivalent board were solved. Finally, the free modal and transmission loss of the equivalent plate model were carried out by simulation analysis. Through comparative analysis of simulation data between the floor and the equivalent plate model, it was proved that the equivalent plate model was rational.After a theoretical analysis, experimental testing and simulation analysis, it’s proved that the equivalent theory of the vibration modes is rational. And the equivalent homogeneous single-plate model of hollow profiles is received. Through the simulation analysis, the frequency range of reasonably applications of equivalent board is given.