Time Domain Simulation of the Maneuvering of a Vessel in a Seaway

Abstract

This paper presents a new unified seakeeping-maneuvering simulation model valid for surface ships and underwater vessels. If the total ship motions are derived from the traditional formulations for the hydrodynamic and maneuvering models, considering them as two separate problems, the results will be inconsistent. It has therefore been necessary to develop a unified formulation which calculates the total ship motions including both the maneuvering aspects and the wave induced motions. Focus in this study has been on submarines. Examples of application of the developed time domain simulation code are given. These are simulations of the response and corresponding control plane forces of a submarine in straight line motions in regular waves at given headings. The developed code can also be used to e.g. simulate turning circles. This has been conducted for the same submarine, and the results are compared to experimental results. Additionally, simulations of the response of a surface vessel (Wigley hull) with forward speed in regular waves at given headings are presented. In this case only the potential forces are considered. The results from the simulations are used to establish motion transfer functions, which are compared to other numerical and experimental results. There are some limitations in the developed method which affects the application area of the numerical code. This refers particularly to underwater vessels. This will be addressed, and further possible development of the method will be discussed.

Is Full-autonomy the Way to Go Towards Maximizing the Ocean Potentials?

“…In 2013, the two-time scale model was applied to irregular seas and validated for a container ship (Skejic and Faltinsen, 2013). Hermundstad and Hoff (2009) implemented a time domain unified model on submarines and compared with experimental results. It was argued that the used unified model did not describe the diving maneuvers correctly because the depth dependency of the coefficients was not incorporated.…”