ON THE MECHANISMS OF VIBRATIONAL INSTABILITY IN A CONSTRAINED ROTATING STRING

✍ Scribed by JIFANG TIAN; STANLEY G. HUTTON

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 197 KB
• Volume: 225
• Category: Article
• ISSN: 0022-460X
• DOI: 10.1006/jsvi.1999.2237

✦ Synopsis

A relatively simple mathematical model involving an idealized rotating string constrained at one point is used to develop an understanding of the basic physical mechanisms that govern the development of unstable lateral vibration response. Equations de"ning the relationship between the interactive inertial, damping, elastic and applied forces are presented. Analysis of these equations leads to a clear understanding of the physical mechanisms involved in the development of divergence and #utter instability mechanisms. New developments involve the identi"cation of the energy #ux into the rotating system and an explanation of the role of circumferential forces caused by interaction with the non-rotating constraint. The equations developed suggest methods for minimizing the instability regions that are encountered in such rotating systems when operating above their lowest critical speed. Numerical examples are presented for the case of a rotating string to illustrate its instability characteristics when constrained by a single degree of freedom viscously damped system.