No abstract

Lifeboats are important for safety of passengers and crew on floating vessels and offshore platforms. They need to be designed so that evacuation can be performed quickly and safely in case of emergency. This requires that the lifeboat is not damaged during water entry, that it moves afterwards away from the dangerous area, and that accelerations experienced by occupants do not exceed allowable limits. In this paper, the use of numerical simulation is proposed as a tool for design and optimization of lifeboats. While experimental studies will still be needed to validate the final design, the use of simulation can greatly increase the number of parameters relevant for structural integrity and wellbeing of occupants that can be studied in the design process. In a simulation, full size and realistic operating conditions can be realized, and the computational effort is affordable even for a small design group. The comparisons with experimental data performed so far indicate that the accuracy of simulation is comparable to that of an experiment.

No abstract

No abstract

Lifeboats are important for the safety of crew on oil platforms and marine vessels. Their design has so far been mostly based on experimental studies. However, the large number of factors which influence the loads on the lifeboat structure and its occupants makes optimization studies by experimental means both time-consuming and expensive. Besides, many effects cannot be studied at laboratory scale due to the inability to match all similarity parameters, and certain conditions cannot be realized in a laboratory. Numerical simulations based on modern computational fluid dynamics (CFD) methods could complement experimental studies if proven to be sufficiently accurate and efficient. The aim of this study is to demonstrate that this indeed is the case: comparisons between experimental data and simulation results performed by the authors so far indicate that the achieved accuracy in numerical simulations is comparable to the accuracy of experiments. It is also shown that a simulation of one drop test can be performed with sufficient accuracy in one day on a single core of a personal computer. Together with a computational method which uses overlapping grids to simplify the handling of lifeboat motion and specification of initial and boundary conditions, parametric studies of lifeboat water entry have thus become practicable.