Reducing excessive vibration of rigid rotors mounted with hydrodynamic bearings by controlled excitation of the rotor supports

Title:

Reducing excessive vibration of rigid rotors mounted with hydrodynamic bearings by controlled excitation of the rotor supports

Creator:

Ferfecki, Petr and Zapoměl, Jaroslav

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:461f046d-1425-40c6-96f7-713e75dffdcc
uuid:461f046d-1425-40c6-96f7-713e75dffdcc

Subject:

rigid rotor, hydrodynamic bearings, active vibration control, and suppression of excessive vibration

Type:

model:article and TEXT

Format:

bez média and svazek

Description:

The flexible supports make it possible to decrease the forces transmitted between the working machines and their foundations. As rotating machinery, the hydrodynmic bearings exhibiting compliance and considerable damping together with high load capacity are ofen used for this purpose. Nevertheless, on certain operating conditions, the hydraulic forces produced in the thin oil film can destabilize the rotor equilibrion position, which consequently leads to development of the rotor self-excited vibration of large amplitude. There are several ways how to increase the critical speed of the rotor rotation at which the self-excited vibration starts. Recently, the attention was focused on increasing damping in the rotor supports or on modification of the bearings geometry. At present time there are available many active control devices working on various physical principles. In this paper the research of the concept based on controlled kinematic excitation of the bearings shells is carried out. The performed computer simulations prove that the investigated technique enables to reduce amplitude of the self-excited vibration and to increase the rotor angular speed of rotation, at which the self-excited vibration begins. Suppression of the rotor oscillation is always connected with increasing the force by which the turning rotor acts on its stationary part. The developed computational procedures and results of the performed analyses are intended for finding properties and behaviour of the active control devices for mitigation of excessive vibration of rotating machines and to contribute to their proper design in this way. and Obsahuje seznam literatury

Language:

English

Rights:

http://creativecommons.org/licenses/by-nc-sa/4.0/
policy:public

Coverage:

419-431

Source:

Engineering mechanics: international journal for theoretical and applied mechanics | 2012 Volume:19 | Number:6

Harvested from:

CDK

Metadata only:

false