Assembly Accuracy Prediction And Optimization of Aeroengine Rotor Under The Separation Condition Of Assembly And Measurement

Abstract

The measurement and assembly of aeroengine rotor are separated from each other, the uncertainty of the test position leads to the test data cannot reflect the geometric characteristics of the rotor itself, which makes it difficult to accurately measure and predict the assembly accuracy. Combined with the fact that the geometric characteristics of parts / components are not related to the measurement datum, an assembly accuracy test and prediction method is proposed to reduce the datum deviation and ensure the consistency of test data. Firstly, the small displacement torsor is used to describe the datum deviation, the inverse matrix transformation is applied to reduce the datum deviation, and the datum independent matrix is utilized to express the pose characteristics of the parts / components, which provides the data basis for the accurate prediction of assembly accuracy. Then, the pose transfer model based on the datum independent matrix is established, which is more comprehensive and clearer than the traditional accuracy prediction model. Furthermore, a direct optimization method is also established, which is more efficient than the traditional genetic algorithm. The assembly experiment of aeroengine rotor shows that the model and method proposed in this paper are beneficial to reduce the coaxiality of the front and rear fulcrum and they can better reflect the geometric characteristics of the rotor itself. The related research also has reference significance for other large-scale and high-precision mechanical product assembly.

Unbalance Prediction of Low Pressure Rotor Based on Mechanism and Data Fusion

“…When the two disks are bolted together, the shape and position errors lead to uneven force in all parts of the connecting surface after assembly [2]. The form and position errors of all levels of disks are transmitted and accumulated along with the connecting surface of the joint, making all levels of disks produce eccentricity and deflection.…”

“…The low-pressure rotor of an aero-engine has an impact on the vibration response of the whole machine when it is rotating at high speed. Too much unbalance will make the low-pressure rotor rotate at high speed when the unbalance force rises, thus causing the whole machine to vibrate, and even lead to the blade touching to grind, and then affect the reliability and service life of the aero-engine operation [1][2][3][4]. Depending on statistics, about 60% of aero-engine vibrations are caused by rotor unbalance [5].…”

Digital Simulation and Analysis of Assembly-Deviation Prediction Based on Measurement Data

“…Forced assembly occurs even more frequently, which has a significant impact on the quality, performance and lifespan of gas turbines and other important equipment. In some cases, it even causes damage to all the equipment [3].…”

Research on Rotary Parts Vibration Suppression Based on Coaxiality Measurement and Unbalance Constraint

“…Sun Chuanzhi et al [12] analyzed the cumulative process of error transformation in the assembly process of multi-stage rotors and obtained the cumulative eccentricity error of each stage after multi-stage rotors assembly by using space vector projection method. Liu Jun et al [13] proposed a technique to reduce the problem of rotor misalignment by combining the two-objective optimization of rotor stacking coaxiality and unbalance and studied a method to predict the geometric deviation between the rotating axis and its own centroid axis based on the error measurement of single-stage parts.…”