Improving the Stability and Critical Speed of Rotor Bearing System By Using External Damping Source

M. Hammza, Tariq; R. Hmoad, Nassear; N. Abas, Ehab

doi:10.30684/etj.v38i3A.344

	Improving the Stability and Critical Speed of Rotor Bearing System By Using External Damping Source
Engineering and Technology Journal
Article 4, Volume 38, 3A, 2020, Pages 319-324 PDF (573.2 K)
DOI: 10.30684/etj.v38i3A.344
Authors
Tariq M. Hammza^* ¹; Nassear R. Hmoad²; Ehab N. Abas³
¹University of technology, Electromechanical Engineering Department, Baghdad, Iraq. [email protected]
²University of Baghdad, College of Engineering, Aeronautical Engineering Dept. Baghdad, Iraq. [email protected]
³Ministry of Higher Education and Scientific Research ,Studies and Planning and Follow Up Directorate Baghdad, Iraq. [email protected]
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
Rotor; Critical speed; Ball Bearing; fluid Film Journal Bearing

References
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