Authors

1 University of technology, Electromechanical Engineering Department, Baghdad, Iraq. 50298@uotechnology.edu.iq

2 University of Baghdad, College of Engineering, Aeronautical Engineering Dept. Baghdad, Iraq. nassear_machine@yahoo.com

3 Ministry of Higher Education and Scientific Research ,Studies and Planning and Follow Up Directorate Baghdad, Iraq. ehab19722002@gmail.com

Abstract

Improving the essential factors of rotor bearing system are the aim of this study. In addition to the presence of two ball bearings to support the rotor, two additional fluid film journal bearings have been used as an external damping sources. The ANSYS Mechanical APDL 18.0 was used to model rotor bearing system with existence of two additional fluid film journal bearings. Matlab software has been used to achieve the analytical solution. The results clearly showed that the maximum response displacement strongly decreasing and the critical speed has been enhance by using an external damping source as well as the stability of rotor bearing system has been improved due to increasing damping of rotor system where the response displacement decreasing by 99% and critical speed increasing by 0.6% when using an external damping sources. The position of damping source has an important effect on the maximum response displacement and the more decreasing value of response displacement has been achieved when the damping source become as close as possible to the disk position.

Keywords

 
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