Dynamic Characteristics Of Multi-rotor System Analysis And Applied Research

This paper introduces comprehensively the present calculating methods of aero-engine rotor system dynamic characteristics, and make a deep dicussion of Whole Transfer Matrix (WTM) method, Riccati Transfer Matrix method. Based on both methods, an improved WTM method and a new method for calculating steady-state unbalance responses of twin-rotor system are presented. According to the calculating methods of current rotor structure dynamic characteristics, a general calculating program of analyzing aero-engine rotor system is developed.The critical speeds and modes are calculated for the cases of single rotor system, twin-rotor system of an certain areo-engine by using the method proposed in this paper, the results show that the methods are very valuable comparing with exact soultions in relating literatures.. When the unbalance response of rotor system is analyzed, the calculation formulas of twin-rotor system with no squeeze film damper (SFD) are derived, the effects of unbalance levels and distribution on steady-state dynamic response are investigated, also the transient motion equations of simple rotor-bearing system are established.On the research of these methods in this paper and the present calculating methods of rotor dynamic characteristics, the application program (ARDAP) is developed and it can expediently analyze such as critical speeds, steady-state unbalance response and transient unbalance response of single rotor with SFD. Some numerical examples are calculated, the results show that this general program has merits of calculation accuracy, good stability and high efficiency. The methods and results deduced in the paper are very useful both in the design and development of multi-rotor system.