AbstractA new technique for the rotor whirl damping in rotating machinery, based on the elastic suspension of the journal boxesand the use of dry friction surfaces normal to the shaft axis between their supports and the frame, is here analysedtheoretically for several cases of rotor systems characterized by mass and constraint asymmetry, where gyroscopic effectsare to be expected and conical whirl motions may grow up. The critical flexural speeds can be easily cut off by an adhesivestate of the supports and the whirl amplitude can be minimized as well throughout the remaining sliding range. Confiningthe operative angular speed of the rotor in the range of adhesive contact between the dry friction surfaces, no significantincrease of power dissipation or heat production has to be ascribed as a whole to this type of suspension system, whosetask is just to suppress the resonant peaks when passing the critical speeds. On the other hand, the rubbing surface wearcan be easily compensated in the long run by use of suitable spring devices to close the friction contact. The uniqueness andthe stability of the steady motion are proved, both in the absence and in the presence of possible additional viscous sourcesof dissipation. It is also shown how the destabilizing influence of the shaft material hysteresis can be counterbalanced bythe other external dissipative forces.r 2008 Elsevier Ltd. All rights reserved.
|Numero di pagine||25|
|Rivista||Journal of Sound and Vibration|
|Stato di pubblicazione||Published - 2009|
All Science Journal Classification (ASJC) codes