| With the development of urbanization in our country,the number of expressways and high-speed railways has multiplied,and the noise problem is becoming more and more serious.Noise problem is not like other problems,it has a strong randomness,resulting in increased difficulty to prevent.And the noise problem is accompanied by almost every aspect of our daily life,which makes our daily life is greatly troubled.In order to reduce the noise problem and reduce the noise decibel,the main research methods are focused on the isolation of sound source and the transmission path of human ear.In this paper,the reverberation room of acoustical standard laboratory is used as the background,simulation software is used to simulate the experimental conditions in the reverberation room,establish the acoustic-solid coupling simulation model,obtain the data parameters that cannot be obtained in the laboratory,and compare with the existing experimental results.This paper firstly introduces the acoustic theory.Based on the basic acoustic quantity,several methods of acoustic insulation quantity calculation are introduced,and the formulas for calculating the acoustic insulation quantity of single-layer and double-layer plates are obtained by wave transfer method.The change relation of sound insulation curve is analyzed by formula.Three evaluation indexes of sound insulation performance are presented,and the advantages and disadvantages of each evaluation index are analyzed.Then the sound insulation quantity is selected as the expression of sound transmission loss.Based on the three basic physical formulas of acoustics and the wave transfer method,the theoretical formula for calculating the reverberation sound field is derived,and finally the calculation expression of the reverberation sound field is obtained.Combined with the theory part,the structural coupling equation of the simulation process is analyzed.Combined with the actual situation,the multi-physical field simulation software is applied to simulate the experimental process of reverberation chamber — reverberation chamber,and the simulation idea of the simulation software is introduced.The model is modeled for the specimen and the reverberation chamber,and the boundary conditions of the model are set to make the simulation model restore the experimental process to the maximum extent.The model grid is divided according to the grid division requirements of acoustic simulation.In the process of simulation,two sound-solid coupling methods are used to make the sound field conditions of the sound chamber and the sound receiving chamber are completely diffused.The 1/3 octave was used to calculate 13 octave nodes in the range of20-1000 Hz,and finally the sound pressure cloud map under different octave frequencies was obtained,which could see the sound pressure changes in the reverberation room more clearly than the experiment.The sound insulation quantity of different specimen areas was analyzed,and the change rule was analyzed with the wave transfer method.As the specimen area gradually increased,The sound insulation capacity of the specimen first increases and then decreases,and a specimen area with the largest sound insulation capacity will appear.The sound insulation capacity of the specimen will rise in a wavy way in the low frequency area.When the frequency rises to a certain level,the sound insulation capacity will gradually increase.The change of sound pressure at different heights in the standard reverberation room was analyzed.With the center height of the specimen as the origin,the sound pressure towards the lower part was slightly lower than that towards the upper part,which was determined by the reverberation degree of the reverberation field.Change the sound position of the sound source,and analyze the change of the internal sound pressure level under the condition of meeting the construction standards of the reverberation chamber.Finally,the change of the energy of sound wave on the internal stress of the specimen is analyzed. |
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