quick overview :

Torsional Oscillations Unit

Description of Torsional Oscillations Unit The Torsional Oscillations Unit enables to illustrate and investigate the torsional oscillations of single rotor, multi-rotor and geared  systems. The unit basically consists of a rigid frame that have some fasteners which enable to situate its different elements. It also has a set of helical  springs to simulate long flexible shafts, and a set of discs of varying mass moment of inertias. Suitable gears of various sizes are also  provided to change the gear ratio. Fasteners offer the possibility to modify the arrangement of discs and gears, as well as the use of different types of spring. That enables the  study of the different existing systems. The natural frequencies are of flow order and can be counted. Besides, a line drawn axially on the spring serves to illustrate the elastic line  and facilitates the experimental location of the nodes.