Localized fatigue failure analysis of aluminium crewboats due to propeller pulse loads: A case study

The present paper reports on the development and implementation of a finite element analysis methodology for the prediction of propeller induced fatigue failure in the structure of aluminium vessels. The work covers practical recommendations for the generation of a suitable combined beam-shell finite element model, the determination of the propeller pulse load magnitude and distribution as well as the implementation of a Miner’s cumulative fatigue analysis. In order to establish its validity, the proposed methodology is used to analyse two different structural arrangements of an existing, 18 m long, aluminium crewboat with reported fatigue problems. Numerically predicted failure locations showed excellent agreement with the actual failure zones