Sensitivity analysis of torsional vibration behavior of the shafting of a turbo generator set to changes of its mechanical parameters.

Autor: Xie, Danmei, Liu, Zhanhui, Zhang, Hengliang, Yang, Changzhu, Dong, Chuan
Zdroj: Frontiers of Energy & Power Engineering in China; Oct2007, Vol. 1 Issue 4, p483-486, 4p
Abstrakt: Aiming at a 300 MW turbo-generator model, the sensitivity of natural torsional frequencies and modes of torsional vibration (TV) to the rotational inertia and stiffness of the turbo-generator were analyzed. Calculation results show that the variation of the rotational inertia or stiffness either of the rotor system as a whole (namely shafting) or only locally may both remarkably influence the TV characteristics of the rotor. The influence of localized variation is still notable although it is not as great as that of the rotor as a whole. The segments on the shafting, which contribute more to a certain mode of vibration, have a greater influence on the pertaining order of TV. Compared with the modal shape, a larger slope can be observed at these sections of the rotor for the particular mode. Thus, frequencies can be modulated by modifying the local construction of the rotor to make the natural TV frequency of a certain order avoid some specific value, herewith arriving at the objective of tuning. Therefore, it is very important, in the course of modeling for the purpose of studying the TV of the shafting of a turbo-set, to accurately determine the structural parameters of parts that have a relatively sensitive effect on the TV behavior. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index