Static And Dynamic Characteristics Analysis Of The Gearbox Shell Of A Light Truck And Multi-objective Topology Optimization

The gearbox shell of a light truck is treated as an important component of the vehicle transmission system,whose structural performance directly affect the performance and life of the vehicle.During normal operation,the shell may produce large stress and deformation under a variety of complex loads,which seriously affect the stationarity and accuracy of the gear transmission.The poor vibration conditions can also cause the shell to break down.In this context,to obtain an optimal shell structure of multi-performance integrated,the static and dynamic characteristics analysis of gearbox shell and multi-objective topology optimization is necessary,which has important theoretical significance and engineering practical value for improving the design level of gearbox and other shell structures.In this paper,three-dimensional model and finite element model of the gearbox shell of a light truck are established respectively by using SolidWorks and HyperMesh software.On this basis,the static analysis of gearbox shell in the first gear and reverse gear working conditions is carried out firstly.According to the stress and strain distribution,we know that the strength of the shell in two conditions satisfies the requirement,but deformation of the bearing hole and its surrounding area in middle and rear shell is large,and stiffness needs to be strengthened.Then,the gearbox shell has been carried out modal analysis with the method of simulation and experiment.Comparing modal parameters of simulation and experiment,the finite element model and modal analysis of the gearbox shell are verified to be correct and rational.In addition,the frequencies of the engine excitation and gear meshing are compared with natural frequency of the shell,and the resonance frequency of the shell is found,which provides the theoretical basis and basic data for multi-objective topology optimization.Finally,based on multi-objective topology optimization theory,a static and dynamic multi-objective topology optimization model of gearbox shell is established,and the weightcoefficients in the model are determined by referring to the analytic hierarchy process.On this basis,the multi-objective topology optimization of the gearbox shell is carried out using the OptiStruct module.After optimization,the structural stiffness and natural frequency of the gearbox shell are improved greatly,and the natural frequency of the shell effectively avoid the gear meshing frequency.The results show that the static and dynamic multi-objective topology optimization can improve the static and dynamic characteristics and realize lightweight design of the shell,which lays a foundation for the improved design of gearbox and other shell structures.