Modeling, simulation and vibration testing of high power air blower rotating system

Abstract

In this paper vibration of high power air blower machine with high power induction electric motor, gear multiplier box and air blower rotating on journal bearings was estimated, modeled and simulated and experimentally tested in situ. Monitoring both absolute vibration of housing-type bearings and relative vibrations of a rotor shaft was provided with modern Condition monitoring, protection and diagnostic systems. Insufficient 1X frequency dynamic stiffness of a rotating system is stated to be main reason of high vibration amplitude of the electric motor that let to bent rotor. It is shown that the design of an electric motor does not meet the air blower maintenance requirements: i.e. an increases in the load the curvature of the rotor increases to an unacceptable level, the safety operation of the blower too dangerous. The experimental test of gear multiplier box show increased high frequency vibrations in helical gears. The blower journal bearings technical condition was estimated through measurements of relative vibration displacements on shaft inside the bearings. The task of these researches is to determine the reasons of the increased vibration intensity of the rotating system, identification of vibration sources and meet reliability requirements of machine.