Torsional vibration characteristics of power transmission system

Torsional vibration is a frequent perturb for heavy rotating and high speed machinery. Development of large torsional vibrations produce torsional stresses which leads to increase in bearing loads and results in generation of cracks in the high stress areas of the transmission system and propeller. So, it is important to model and analyze the torsional characteristics of Power transmission system. The information obtained regarding torsion vibration characteristics will be useful to study the system dynamics and prevent premature failure caused due to resonance at critical speeds. In this paper, torsional vibration analysis is carried out for a marine power transmission system. The propulsion system is modeled as a flexible shaft with multiple inertias as lumped masses and shaft sections with torsional stiffness. Holzer method is employed to calculate the torsional resonant frequencies and their corresponding mode shapes. An algorithm for Holzer method is designed and programmed using MATLAB software. (paper)