The torsional vibration package “TORSION V6.1” uses a finite-element based formulation for performing damped and undamped torsional natural frequencies, mode shapes, stability, steady-state response, and time-transient response of complete mechanical drive trains. TORSION consists of three modules: TORNAT, TORHRM, and TORRSP integrated by TORSION’s module messenger. The messenger controls the modules to provide a complete torsional vibration analysis environment.
One of TORSION’s important advantages is that the package accepts/imports models generated with the rotor dynamics package ROTLAT. Thus, TORSION can use the ROTLAT models (without bearing influence).
Furthermore TORSION has advanced modeling features and capabilities including the modeling of multi-shaft and multi-branch systems, coupling stiffness and damping, gear tooth flexibility, stiffness / mass / inertia diameter, torsional springs to ground, various types of external excitations containing harmonic parts, synchronous motor start-up torque (including complete run-up), dynamic load torques (e.g. by a recip compressor), user specified time varying torques, electrical faults and start-up scenarios for motor and generator, and many others.
Among the features incorporated in TORSION package are electrically-induced, time-varying exciting torques associated with generator and induction motor operation that include:
Generator
Induction Motor
TORSION results include:
NATURAL FREQUENCY, MODE SHAPES
(Module “TORNAT”)
STEADY-STATE RESPONSE
(Module “TORHRM”)
TIME-TRANSIENT RESPONSE
(Module “TORRSP”)
Detailed information on TORSIONAL VIBRATIONS including advanced engineering service are presented on a special site.
Figures and screenshots provided with kind permission of RBTS.
