Dynamics Modeling And Parameter Sensitivity Research Of Gear Transmission System Based On Superelements

Involute spur gear transmission has been widely used due to its unique advantages.Its application places include important military defense equipment such as military helicopters.The gear system has complex transmission characteristics,many coupling factors and is difficult to characterize,for accurately predicting the gear transmission system.The vibration level and optimization design face problems such as long research cycle and huge cost.Based on the superelements method,this paper establishes a high-precision and high-efficiency dynamic analysis model of the gear transmission system,and conducts research on the sensitivity of the dynamic parameters of the gear transmission system.The main research contents are as follows:(1)Based on the superelements modeling method,the gear-rotor system and the box superelements model are established.Taking the single-stage spur gear reducer as an example,the error source in the box superelements modeling is analyzed by the box modal experiment and the maximum error was corrected to verify the accuracy of the box superelements model.Finally,the accuracy of the overall dynamic model of the system was verified by the vibration response experiment.(2)Combining the dynamics model of the gear transmission system,the intrinsic characteristic calculation principle and the introduction of the modal energy concept are used to analyze the parameters of the inherent characteristics of the system.Firstly,the “same frequency”phenomenon of the inherent characteristics of the system after coupling the box is summarized.The influences of box material parameters,meshing stiffness and support stiffness on the natural frequencies of the system are analyzed.Secondly,the dynamic response of the system before and after the coupling box and the changes of the box material parameters and system excitation parameters are analyzed.The influence of each parameter on the dynamic characteristics of the system is summarized.(3)The meshing stiffness and bearing stiffness in the gear transmission system are the “bridges” of the dynamic model coupling into the system.From the stiffness parameters of the gear transmission system,the stiffness parameter is analyzed by the global sensitivity analysis method(sobol index method).The global sensitivity index of dynamic response grasps the coupling relationship between the stiffness parameters of the system.Finally,the multi-objective optimization of the system stiffness parameters is carried out by increasing the first-order natural frequency and reducing the radial vibration acceleration of the gear,which provides a theoretical basis for the gear system to avoid resonance and vibration reduction design.