Vibration suppression of rotating machinery is an important engineering problem. In this paper, a review of the research work performed in real-time active balancing and active vibration control for rotating machinery, as well as the research work on dynamic modeling and analysis techniques of rotor systems, is presented. The basic methodology and a brief assessment of major difficulties and fu...

As one of the most common faults, rotor imbalance in a turbocharger will give rise to the bending vibration, which may cause damage to and even destroy the bearings and impellers. Therefore, it is necessary to detect rotor imbalance as early as possible. The present paper develops a mathematical model for investigating the rotor dynamic characteristics of a commercial automotive turbocharger su...

The digital signal processing based on new microprocessor technology allows us great success in machines protection, with very acceptable economic investments today. Additionally, including vibration-diagnostics monitoring of machines in addition with analytics methods, it is possible monitoring and quantification dynamics parameter of machine. By means analysis dynamics behavior of rotor, it i...

A method of multi-objective optimization is proposed to improve the quality of crushed materials and vibration performance of the rotor. This method is driven by the first order natural frequency and the radius of the rotor. The Central Composite Design (CCD) experiment method is used to guide the selection of appropriate structure finite element analysis samples in design space. The quadratic ...

The faults of rotating machinery monitored by fixing the sensors on rotor directly brings some problems such as difficulty in fixing the sensors, poor universality and so on, while it brings some advantages such as rapidness, convenience and good universality and so on by fixing the sensors on the base. Since the base is far away from the fault source, the collected vibration signals are relati...

The vibration and noise of permanent magnet synchronous motors (PMSM) are mainly caused by unbalanced magnetic pull (UMP). This paper aims to investigate nonlinear vibration in PMSMs. Firstly, the analytical model of the air-gap magnetic field with an eccentric rotor in PMSM is studied, and the analytical model is verified by the finite element method. Then the dynamic model of an offset rotor-...

In electric machines the electromagnetic fields interact with the deformations of machine structures. At low frequencies the electromagnetic system may couple distinctly with the mechanical one. This electromechanical interaction changes the vibration characteristics of the machine; e.g., it may induce additional damping or cause rotordynamic instability. To study these interaction effects, an ...

A traveling wave-type ultrasonic motor (USM) has a self-locking characteristic due to a static frictional force present when its power supply is turned off, because its rotor is pressed strongly to the stator in the USM. We propose a pulse width modulation (PWM) method in consideration of this self-locking characteristic in order to control the motion of USM. The vibration waveform and the driv...

In this paper the design, fabrication and analysis of behavior by full-scale ver-ification testing for the tail rotor blade of composite laminated materials for a heavy transport helicopter is given. The verification test program for the tail rotor blade encompassed static and dynamic test-ing. The static tests of the blade involved experimental evaluation of torsional and flexional blade stif...

Disk imbalance is a condition in which the center of mass of a rotating disk is not coincident with the center of rotation. Imbalance in a rotor system is unavoidable and it cannot be completely eliminated. Due to some reasons, such as porosity in casting, non-uniform density of material, manufacturing tolerances, and gain or loss of material during the operation, there is imbalance in rotors. ...