The Dynamic Response Analysis Of Aero-engine Rotor With Intermediary Bearing

Because aviation engine performance for aircraft performance has a more direct impact, so it is especially important for the engine's reliability and stability requirements. With the rapid development of computer technology, finite element method is increasingly becoming the main methods of rotor dynamics. In this paper, aircraft engines, rotor system as the research object, carry out the following work using the finite element method: the casing stiffness rotor system are studied; the use of finite element method for the high-pressure rotor and a low pressure rotor simulation, and obtained the high-pressure rotor low pressure rotor Campbell diagram; stiffness and speed ratio on the critical speed dual-rotor system were studied; high-pressure rotor and a low pressure rotor analysis on unbalance response law, for different rotor unbalance amplitude were studied.Studies have shown that: the casing stiffness to the support rigidity of the entire rotor system has a great influence. High pressure rotor stiffness greater than the low-pressure rotor. Single-rotor system capable of rotor vibration mode mainly during the first critical speed of the turbine swing, second-order vibration mode mainly the critical speed of the swing compressor. Incentive-based low-pressure rotor critical speeds of the first three with increasing speed ratio increases, mainly in the high-pressure rotor excitation first three critical speeds with increasing speed ratio decreases. When the stiffness increases, the critical rotor system when speed gradually increased, and the amount of change gradually reduce and eventually will tend to a certain value. Low pressure compressor rotor unbalance sensitivity of parts for turbine parts more than high. High pressure turbine rotor parts of the sensitivity of the imbalance is higher than the compressor parts. Unbalance the presence of two co-rotor will significantly increase the amplitude of the two reverse unbalance amount will significantly reduce the amplitude of the rotor. Study found that when the unbalance is changed, the maximum peak all appeared at the same frequency and amplitude peaks with increasing unbalance increases.For aviation engine dynamics response analysis used herein, the finite element method to simulate, for a mediation rotor bearing system is analyzed, obtained resonance of aircraft engines and aircraft engine speed range of shapes for aircraft engines, designed to provide a certain reference for further study of domestic air engine provides the foundation.