| The dynamic characteristics of the aero-engine stator system play an important role inresearching the stator system dynamic characteristics. It is necessary to know the exact statorsystem dynamic characteristics for studying dynamic characteristics of rotor system,especially the critical speeds, the modes and the transmission characteristics. To solve thisproblem, finite element method (FEM) is used to compute the dynamic behavior and dynamicstiffness of aero-engine stator system.The paper first discusses the basic structural dynamic theory in finite element method, aswell as explores the reasonable simplification, which is about of an aero-engine complexstator structure. According to the engine design drawings, the stator system model isestablished using UG software. Finite element method is adopted in calculating the modes of itincluding the casing using ANSYS, obtain the top fifty orders of modes. According toHarmonic Response Analysis of the basic theory in the modes analysis based on the statorsystem Harmonic Response analysis, stator supporting system in harmonic excitation forceobtained under the pre-supporting, intermediate supporting and post-supporting at thefrequency response curve. According to the definition of dynamic stiffness, this papercalculates the pre-supporting, intermediate supporting and post-supporting dynamic stiffnesscurve using MATLAB. The formulae of dynamic stiffness are fitted basis on the curves of allthe support dynamic stiffness.Finally, for verification of stiffness calculation results, each of the supports dynamicstiffness obtained is put into a program to compute critical speeds. The calculation results ofcritical speeds are reasonably agreeable with the critical speeds given in engine operationinstruction. Analysis shows that the finite element method analysis of dynamic behavior ofstator system used in this paper works well. The calculation result is reasonable, which hassome reference value for engine vibration analysis. |
PDF Full Text Request