Study on the behavior of benchmark container ships in regular waves

Abstract

The study of the behaviour of ships in the real sea has become a real challenge in recent years due to climate change, especially in the European sea basin. One of the main categories of types of ships that cross these waters are transport ships. The development of the economy and trade have a major influence on this type of ships, which must be studied and improved in order to be fully exploited. Investigating the ship’s behavior is not a new topic, but the changing environment of the transport ship’s specifications requires continuous study. An alternative to model testing is the use of numerical simulation through which performance can be fully evaluated using only computers, without the need to produce a scale model for testing. Due to improved computer performance, but also the disadvantages of towing testing, numerical simulations have become increasingly popular for determining ship characteristics. The shorter time in which results can be obtained, as well as the ease of controlling and changing the input parameters, contributes to the preference to use numerical simulations, to the detriment of basin tests. In this paper, the behavior of a Post-Panamax benchmark container ship in regular waves was studied. Numerical simulations were performed using SHIPFLOW MOTIONS, a solver that treats potential nonlinear flows for regular waves and provides accurate results by the free surface potential flow panel method. For our case, the simulations were performed for a range of six speeds corresponding to Froude numbers ranged between 0.174 and 0.218, for five nondimensional wavelengths (λ/Lpp) and for four wave heights. Because body discretization is one of the main factors for obtaining accurate results, an additional study was conducted in calm waters on body refinement and the influence that the mesh has on results, for a range of ten grids with different densities.

Hydrodynamics Performance Prediction of a Full-Scale Ship

“…In order to evaluate the numerical simulation error and uncertainty, a grid analysis was performed for three grids based on the Richardson extrapolation [24]. Similar grid convergence tests have been also reported by [7], [25], [26]. The smooth hull configuration at the speed of 8 knots was considered for the grid convergence test and the results obtained for the total resistance are summarized in table 5, where Si represents the computed solution for fine meshapprox.…”