Sensitivity Analysis Of Engine Transmission Gear Installation Parameters To Dynamic Characteristics

The gear transmission system is one of the key components of aero-engines and works in complex environments such as high temperatures and heavy loads.Gear assembly is a key link in the engine manufacturing process,and its performance directly affects the dynamic characteristics of the engine.This article combining the gear assembly inspection items in the national standard,carries out the sensitivity analysis of the assembly parameters of the engine transmission gear to the dynamic characteristics.The specific content is as follows:（1）Based on the lumped parameter method the numerical model of a certain spur gear was established to study the gear behavior characteristics under different loads and speeds.The analysis shows that as the speed increases,the gear’s vibration degree increases;by controlling the load,the gear’s vibration state can be controlled to maintain system stability.（2）Based on the Hertz theory spur gear models with different center distance deviation and parallelism deviation were established to study the dynamic characteristics of gears.The analysis shows that the parallelism deviation causes the gear contact stress to increase,and the gear model with the axis parallelism deviation in the vertical plane is the most sensitive to changes of contact stress.（3）Based on the traveling wave resonance principle the component test of an aero-engine central drive bevel gear was carry out to obtain the traveling wave resonance frequency and speed;based on the structural dynamics theory the modal analysis of the gear was carried out.Analysis shows that the gear has three nodel diameter forward waves and four nodel diameter backward waves resonance.（4）Different bevel gear assembly models containing the axial displacement of the ring gear,the deviation of the shaft spacing and the deviation of the shaft angle,were estiblesh and conducted dynamic analysis.The analysis shows that the gear stress is the most sensitive to the angular deviation of the gear,followed by the axial displacement of the gear ring.（5）Aiming at the driven wheel fracture problem caused by the traveling wave resonance of the bevel gear,the research on the traveling wave resonance characteristics of the gear under the parameter adjustment state was carry out.The analysis shows that adjusting the thickness of the spokes of the driven wheel can avoid the resonance frequency;increasing the damping coefficient of the system can reduce the gear stress.The research content of this paper provides a reference for the analysis of the dynamic characteristics of aero-engine transmission gear assembly parameters.It has certain engineering practical significance.