Analysis And Performance Optimization Of Heat Insulation And Sound Insulation Of Supercharger Cladding

In order to solve the problems of high surface temperature and large radiating noise on the volute of turbocharger,a new type of heat insulation and sound insulation cladding layer was developed by using the idea of blocking and weakening from the propagation path and adopting the structural type of flexible composite metal shell,which can reduce radiating noise and heat transfer.Taking a new turbocharger made in a domestic factory as the research object,the maximum temperature obtained from the test and the noise characteristics as the boundary conditions,the research work on the insulation and sound insulation of the cladding layer is carried out,the performance of the cladding layer is optimized,and the radiated noise is reduced.The main research work includes the following aspects:Firstly,the statistical energy analysis method is used to study the acoustic performance of cladding layer,sound insulation quantity is used as the evaluation index of sound insulation performance,in a semi-anechoic experiment indoor building cladding layer acoustic test bench,the experiment and the simulation result verifies the effectiveness and to study the effect of cladding layer on the noise,in view of the cladding layer composite structures,the analysis of panel materials,the structure parameters such as damping and sound-absorbing material impact on the sound insulation performance of cladding layer,using the method of orthogonal test,determine the key parameters of cladding layer acoustic design,the results show that the thickness of the material changes have bigger influence on the sound insulation performance,followed by material flow resistance and density,The direction of sound insulation performance optimization is indicated.Secondly,using the method of numerical simulation and experimental validation of material heat insulation,heat transfer phenomena of multilayer structure is studied,according to the law of heat conduction is established about material coefficient of thermal conductivity and thickness of insulation model,using insulation model study of different material thickness and the coefficient of thermal conductivity in the environment with the temperature change,the influence of cladding thickness on thermal insulation performance at extreme high temperature was analyzed by steady-state study,thermal analysis was carried out on the commonly used flexible material,the use of theoretical calculation and simulation analysis to verify the thermal insulation material,the results show that the smaller the coefficient of thermal conductivity of materials and thickness increase heat insulation performance of the material in the metropolitan,The thermal conductivity of silica aerogel felt material changes little in the high temperature environment,and the thermal insulation performance is more stable.Thirdly,the performance test of the supercharger was conducted,and the surface temperature and noise spectrum of the volute under rated working conditions were analyzed.It was found that the supercharger noise increased with the increase of the impeller speed,and the relationship between the peak frequency and the blade frequency multiplied.The peak noise occurred in the frequency range of 2000-3000 Hz,which is also the main frequency band for analyzing the sound insulation of the cladding layer.Based on the analysis of the insulation and sound insulation performance of the cladding layer,the design specification of the cladding layer is summarized,provide reference for cladding design.Finally,determining the boundary conditions of the cladding study,conduct the thermal insulation test and sound insulation test of the material respectively in the experiment,build the bench for the thermal insulation test of the material,select different materials for the test,the results show that the cold source surface temperature of the 30 mm thick silica aerogel blanket is kept at 57? after heating for 20 minutes,the thermal insulation effect is stable and reliable;The cladding of different schemes was made,and the prototype of the volute was used to conduct the sound insulation test of the cladding.The results showed that the silica aerogel felt cladding had better sound insulation performance,and the overall sound insulation effect was improved by 2.21 d B(A),which met the requirements of the design index.