Relationship Analysis Between Structure And Acoustic Performance Of A Cabin And Structural Noise Control

As an important part of cab interior noise, structural noise has a significant effect on the NVH character of a cab. It has become a hot research spot that how to analyze and control structural noise, improving the internal acoustic property and acoustic environment of a cab. Based on a mining vehicle cab, lots of analysis and research have been done to guide the low noise design of a cab, which involved in structural dynamic properties analysis, vibration response analysis, acoustic properties analysis, structural noise control and so on.The structural finite element model of the cab has been established and the structural modal analysis was carried out. Based on test and simulation data, the excitation loads of the cab in working condition were solved by inverse matrix method in frequency domain. Taking the loads as boundary condition, vibration response analysis was carried out. The simulation model was verified through contrasting the test data with simulation data. The cab noise was researched by test method and simulation method. The actual noise data of the cab and main sound sources was acquired and the actual noise level of the cab was analyzed. The main noise sources making a greatly contribution to the interior noise of the cab were found out by spectral analysis and order analysis. Acoustic model of the cab was established and the modal analysis on corresponding two acoustic models are carried out. Acoustic-structural interaction was taken into account, in which case, the cab interior noise was forecasted and the acoustic property analysis was carried out and the main noise frequency was identified. Panel acoustic contribution and modal acoustic contribution were obtained through AVT and MATV methods. The parts contributing most to the peek sound pressure and the interior noise of the cab were found out to guide the structural noise control. The structure of the cab was optimized through three aspects which included structure modification, topography optimization and panel thickness optimization. As a result, the structural noise was reduced and the acoustic environment of the cab was improved.