Calculation And Test Research On Sound Insulation Performance Of A Plate With Damping Treatment And Automobile Floor With Noise Control Treatment

In automotive parts sound absorption test,the regular thin plate is often used to simulate the body panel to test the acoustic properties of various sound-absorbing and sound-absorbing materials.The laying of damping material is a commonly used sound insulation and noise reduction treatment method.Acoustic performance is affected by the thickness of the damping material,the laying ratio,and the laying position.In order to improve the sound insulation performance,the sound insulation performance of the thin plate and the damping plate was tested and studied.The car floor is located under the cockpit and can block road and tire noise from passing to the cockpit.Flooring sheet metal parts are difficult to meet the sound insulation requirements,and acoustic packaging is usually applied on the floor to improve the sound insulation performance of the floor.Acoustic packaging is generally composed of multiple layers of materials.Changing the thickness of each layer of the acoustic package for different areas can effectively improve the sound insulation performance.In this paper,the damping plate and the car floor are laid as the research objects.The acoustic response model is used to construct the approximate response surface model.The acoustic performance of the damping plate and the car floor is optimized by the approximate model.Firstly,the damping loss factors of the plate and the plate with damping material treatment were measured by using the impulse response decay method.The damping loss factors of plates with different damping treatment lay ratios was compared.The results showed that the damping loss factor increases with the increase of the damping treatment laying ratio.According to the different installation status of the plate,the damping loss factors of the plate in the suspended state and in the installation state of the sound insulation window were compared.The result showed that the damping loss factor measured in the installation state of the sound insulation window is higher than the damping loss factor measured in the suspension state.Secondly,a sound insulation calculation model of the plate and the plate with damping treatment wad established,and the measured damping loss factor was input into the model to improve the model accuracy.The sound insulation of the plate was calculated,and the calculated results were compared with the test results.The results showed that the calculated values were in good agreement with the experimental values.The sound insulation of the plate with damping treatment was calculated,the calculated results were compared with the test results.The results showed that the calculated values were in good agreement with the experimental values.The calculation results of the two models with different construction methods were compared,indicating that both were consistent with the experimental values.Therefore the simpler model was chosen for subsequent optimization analysis.In the optimization analysis,the experimental design was carried out,and the validated plate SEA model was used to solve the response results of each design point,and an approximate response surface model was constructed.With the goal of maximizing noise reduction efficiency,damping material laying ratio and thickness as the design variables,the plate with damping treatment was optimized,and finally the optimized results were obtained.Finally,a sound insulation calculation model of the automotive floor FE-SEA is established,and the measured damping loss factor was input into the model to improve the accuracy of the model.The calculated value of the floor sound insulation calculation model is compared with the test results.The results showed that the calculated values are in good agreement with the test values,meet the accuracy requirements,and the model accuracy is verified.The test was designed by the central composite design method,and the responses of each design point were solved by the validated FE-SEA sound insulation calculation model,An approximate response surface model of the noise reduction efficiency of automotive floor acoustic packaging with respect to the acoustic packaging material layer thickness was constructed.The response surface approximation model was used to optimize the thickness of each material layer of the car's floor acoustic package.The results showed that the noise reduction efficiency of the floor acoustic package has been significantly improved.