A Multi-Body Dynamic Study on the Torsional Vibrations of a Propulsion Shaft System

The torsional vibrations of the propulsion shaft system in unmanned underwater vehicles (UUVs) could significantly affect the system's fatigue life and acoustic stealth performance. Therefore, it is important to study the torsional vibrations of the propulsion shaft system. This paper establishes a dynamic model of a propulsion shaft system in the unmanned vehicles. The model demonstrates the effects of the torsional stiffness of the shafts and the flexible coupling. The vibrations of the propulsion shaft system are calculated by a commercial software. The effects of the torsional stiffness of the flexible coupling and the rotational speed on the torsional vibrations are analyzed. This work could provide some theoretical foundation for the design and torsional vibration optimization of the propulsion shaft system in UUVs.