Research On Optimization Of Vibration And Noise Performance Of Loader

It is necessary and urgent to design and study the vibration performance optimization of construction machinery.By optimizing the NVH performance of the existing models to be improved in many aspects,it is conducive to the improvement of product competitiveness,the improvement of vibration and noise performance and the improvement of working reliability of loaders.The three-dimensional simulation model of the loader to be improved is built,and then the influence of the components that have a great impact on the vibration and noise performance of the loader,such as the front and rear frames,the cab mounting system,and the working device,is focused on.By using HyperMesh software to calculate the modal of these components,the rigid modal frequency,elastic modal frequency and their corresponding vibration modes are obtained respectively.The model is imported into the virtual lab acoustic simulation software for the next step of vibration and acoustic calculation,and the vibration sensitivity of the frame is obtained and analyzed.Based on the acoustic sensitivity of the cab and the acoustic cavity mode of the cab,the acoustic performance of the cab is analyzed,and the modal shape and plate contribution are obtained.It is ready for the structural optimization and acoustic packaging of the frame and cab.The vibration isolation performance of the cab mounting system is optimized.Based on the angle of vibration energy,the improved genetic algorithm combined with MATLAB software is used to optimize the installation position and stiffness of the shock absorber,which improves the energy decoupling rate of the loader cab mounting system and makes its natural frequency distribution more reasonable.The test results show that the vibration isolation effect of the optimized mounting system is greatly improved.The research shows that by optimizing the energy decoupling rate of the mounting system,the vibration energy of each degree of freedom can be more concentrated,and the vibration performance of the whole loader can be improved.The sound insulation performance of cab and engine compartment is optimized.The noise near the driver’s ear and outside the cab is reduced by acoustic packaging.The results show that the noise near the driver’s ear and outside the loader mainly comes from structural noise rather than air noise,which provides a reference for the research and optimization of NVH performance of loaders and construction machinery.