Document Type : Research Paper


1 Mechanical Engineering Department, University of Technology, Baghdad, Iraq.

2 University of Technology, Assina'a Street, Baghdad, Iraq,

3 Mechanical Engineering Department, University of Technology, Baghdad, Iraq


The most common component of mechanical systems today is rotating machines. In these systems, vibration is caused by rotating components. As a result, to decrease the amplitude of vibrations created by rotating equipment, it’s required to understand the behavior of the system. In this work, the problem of vibrations in conventional bearing systems and the effect of adding active magnetic bearings to rotating machines to reduce the amplitude of vibrations are discussed. In this paper, the vibrations in the rotary bearing system were studied theoretically and analytically by using simulation programs to calculate the natural frequencies and parameters affecting the performance. In the theoretical part, the shaft of the rotating bearing was analyzed by the Jeffcott method depending on several parameters changed with the frequency value to observe the amplitude of the vibrations in the shaft. In an analytical aspect by simulation, a representative model of active magnetic bearings was built using the COMSOL 2020 program, and the effect of adding these bearings on capacitance, vibration reduction, and frequency behavior was examined. SolidWorks 2018 software was used to analyze the magnetic field and its distribution in the magnetic bearing coil. The results indicate that when magnetic active bearings were introduced to the rotating bearing shafts, the vibration amplitude was reduced by approximately 60%. From this work, it can be concluded that the system becomes more stable when the active magnetic bearing is added to the rotating bearing shaft, giving it a more stable and firm nature.

Graphical Abstract


  • Dealing with the Jeffcott method to change the parameters affecting the rotating shaft.
  • The greater the current flowing through the AMB coil at an appropriate air gap distance, the greater the controllability of the rotating shaft.
  • There is a significant reduction in the amplitude of vibrations when the active magnetic bearing is added.


Main Subjects

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