Structural Health Monitoring System Development for Ship Rudders

The applications of energy-saving devices lead to the change of the structural characteristics, compromising its structural integrity. To ensure structural integrity, it is necessary to employ a structural health monitoring system for the ship rudder and control the engine or the propeller based on the system results. For effective structural health monitoring of ship rudders, their responses need to be measured at a suitable location that reflects structural characteristics properly. This study provides recommendations for proper sensor locations for ship rudder structural health monitoring. First, ship rudder modeling was conducted. During the modeling process, the structural complexity of ship rudders was considered. The incorporation of the rudder stock and web stiffeners into the modeling leads to significant differences in mode shapes compared to the conventional simplified ship rudder model. Next, using computational fluid dynamics and finite element analysis, the suitability of the proposed sensor locations was examined by calculating the structural responses of the ship rudder model in actual operational conditions. The results demonstrated that the suggested location can suitably monitor the structural integrity of the ship rudder