In this paper, an identification method to estimate the unbalances is introduced, which is based on the boundary element method (BEM). By using the vibration response measured at some points on the flexible rotor the ...In this paper, an identification method to estimate the unbalances is introduced, which is based on the boundary element method (BEM). By using the vibration response measured at some points on the flexible rotor the unbalances can be identified conveniently. Therefore, the rotor can be balanced without test runs.展开更多
Unbalanced vibration in dual-rotor rotating machinery was studied with numerical simulations and experiments. A new method is proposed to separate vibration signals of inner and outer rotors for a system with very lit...Unbalanced vibration in dual-rotor rotating machinery was studied with numerical simulations and experiments. A new method is proposed to separate vibration signals of inner and outer rotors for a system with very little difference in rotating speeds. Magnitudes and phase values of unbalance defects can be obtained directly by sampling the vibration signal synchronized with reference signal. The balancing process is completed by the reciprocity influence coefficients of inner and outer rotors method. Results showed the advantage of such method for a dual-rotor system as compared with conventional balancing.展开更多
Machines are often subjected to periodic loads, related both to the characteristics of the payload or to the kinematic chains used for motion generation, such as linkages or cam follower mechanisms. The load fluctuati...Machines are often subjected to periodic loads, related both to the characteristics of the payload or to the kinematic chains used for motion generation, such as linkages or cam follower mechanisms. The load fluctuation can cause several inconveniences to the proper functioning of the machines, like shaking forces and moments, vibrations, severe speed fluctuations. Speed fluctuations are a main source of concern since, generally, mechanisms design and optimization is performed considering a constant main shaft speed and a departure from ideal behavior gets worse increasing machine speed. The simpler approach used to mitigate this fact consists in adopting a large flywheel and/or a massive motor, even to drive small loads. More sophisticated procedures add appropriate balancer mechanisms to the machine. This paper, starting from a review of the available literature, presents a theoretical framework to the problem of input torque balancing and defines a methodology for the synthesis of balancing mechanisms.展开更多
文摘In this paper, an identification method to estimate the unbalances is introduced, which is based on the boundary element method (BEM). By using the vibration response measured at some points on the flexible rotor the unbalances can be identified conveniently. Therefore, the rotor can be balanced without test runs.
文摘Unbalanced vibration in dual-rotor rotating machinery was studied with numerical simulations and experiments. A new method is proposed to separate vibration signals of inner and outer rotors for a system with very little difference in rotating speeds. Magnitudes and phase values of unbalance defects can be obtained directly by sampling the vibration signal synchronized with reference signal. The balancing process is completed by the reciprocity influence coefficients of inner and outer rotors method. Results showed the advantage of such method for a dual-rotor system as compared with conventional balancing.
文摘Machines are often subjected to periodic loads, related both to the characteristics of the payload or to the kinematic chains used for motion generation, such as linkages or cam follower mechanisms. The load fluctuation can cause several inconveniences to the proper functioning of the machines, like shaking forces and moments, vibrations, severe speed fluctuations. Speed fluctuations are a main source of concern since, generally, mechanisms design and optimization is performed considering a constant main shaft speed and a departure from ideal behavior gets worse increasing machine speed. The simpler approach used to mitigate this fact consists in adopting a large flywheel and/or a massive motor, even to drive small loads. More sophisticated procedures add appropriate balancer mechanisms to the machine. This paper, starting from a review of the available literature, presents a theoretical framework to the problem of input torque balancing and defines a methodology for the synthesis of balancing mechanisms.
