Dynamic Modeling and Features of GTF Engine Rotor System

To consider the problem that coupling, support position, bearing form and connection mode of the rotor system caused by adding a gear system between the fan and the compressor in the Geared Turbo Fan (GTF) engine, dynamic modeling and features of the GTF engine rotor system are studied in this paper. For the modelling, a star gear meshing model including herringbone teeth and five-way shunt is designed for star gear train; the inner gear ring connected to the fan rotor and the sun gear connected to the low-pressure turbine rotor are meshed through the gear meshing unit, and then the rotor dynamic model including disk, shaft, support structure and membrane disk coupling is established by finite element method. After that, some dynamic features like modal properties and unbalanced responses are analyzed through the proposed dynamic model of the GTF engine rotor system. The combined model of low-pressure unit and star gear unit is established, which can provide an efficient method for the dynamic analysis and design of GTF engine.