Statistic Analysis Of The Assembly Parameters Of Aeroengine And Research On Its Whole Body Vibration

The whole body vibration of aeroengine cause complex vibration stress for structures, and have undesirable influences on the working statuses of accessory system and instrument system. To ensure the safe and stable running, in view of the characteristic of a double-spool aeroengine, an analysis of assembly parameters and whole body vibration correlativity is introduced. This analysis includes:Firstly, for the case of the assembly technique and whole body vibration fault characteristic of an aeroengine, the reasons of faults are investigated. The factors that relate to the whole body vibration in the assembly process are diagnosed, the main assembly and whole body vibration parameters are then selected.Secondly, the main assembly parameters and according whole body vibration parameters of 108 engines of the same type are collected statistically. The sensitivity analysis of assembly and whole body vibration parameters are based on a Monte Carlo model which is programmed in MATLAB. The degree of sensitivity of two vibration parameters against assembly parameters can be estimated through caculation.Thirdly, by using the main component analysis method based on MINTAB, the key assembly parameters are extracted from the main assembly parameters. These key parameters are further validated against actual situation with the structural characteristics of aeroengine considered. The feasibility and accuracy of this method are then confirmed.Fourthly, taking 10 key assembly parameters for each aeroengine as input, and 2 vibration parameters as output, a BP neural networks prediction model is built to predict the whole body vibration parameters.