Experimental Research On Propeller Automatic Balance Considering The Influence Of Aerodynamic Load

The propeller engine has a wide range of applications,such as turboprop engines and propfan engines.However,propeller rotors generate significant noise and unbalanced vibrations during operation.Most methods used in China to address mass unbalance vibrations of propeller rotors involve offline dynamic balancing,which is inefficient and costly.Moreover,aerodynamic unbalance vibrations cannot be suppressed through offline dynamic balancing.Therefore,this paper aims to study the coupling vibrations caused by aerodynamic and mass unbalances of propeller rotors by constructing a simulated propeller rotor experimental platform and applying automatic balancing technology to reduce the vibrations of propeller rotors.The main research contents of this paper are as follows:Firstly,the dynamics analysis of the simulated propeller rotor experimental platform is carried out.The dynamic model of the propeller rotor is established based on the characteristics of the cantilever rotor for vibration analysis.Based on the simulation results of the propeller rotor,measuring points on the simulated propeller rotor test bed are selected for vibration monitoring.Next,the law of aerodynamic and mass unbalance coupling vibrations of the propeller rotor is studied.Firstly,the propeller blade is analyzed for stress based on knowledge of aerodynamics and structural dynamics.Secondly,the vibration response characteristics of the propeller rotor under aerodynamic load are analyzed by comparing the vibration response with and without aerodynamic effects.The experimental study of the coupling vibrations of aerodynamic and mass unbalances of propeller rotors is also conducted.The results show that the coupling vibration of aerodynamic and mass unbalance is a forced vibration dominated by the fundamental frequency,which can be suppressed by changing the mass distribution.Based on the above conclusions,the actual automatic balancing experiment of the propeller rotor’s aerodynamic and mass unbalance coupling vibrations is carried out using an electromagnetic drive mass block type automatic balancing device and corresponding software algorithms.The experimental results show that the automatic balancing device can effectively suppress the coupling vibration of aerodynamic and mass unbalance of propeller rotors,indicating that the automatic balancing technology that changes the mass distribution has a significant vibration reduction effect on the aerodynamic and mass unbalance vibrations of propeller rotors.