Ørjan Selvik

Identification of Nonlinear Manoeuvring Models for Marine Vessels Using Planar Motion Mechanism Tests

A nonlinear manoeuvring model in three degrees of freedom is presented. MARINTEK’s approach to the numerical determination of this manoeuvering model’s parameters is then shown. Finally the process of taking advanced experimental methods, and utilising MARINTEK’s numerical tools to generate an advanced model available for use in VeSim, MARINTEK’s in-house simulator tool, is shown as a demonstration that the model combined with numerical tools is of great use in making manoeuvring predictions.Copyright

Time Domain Simulation Model for Research Vessel Gunnerus

A research vessel (RV) plays an important role in many fields such as oceanography, fisheries and polar research, hydrographic surveys, and oil exploration. It also has a unique function in maritime research and developments. Full-scale sea trials that require vessels, are usually extremely expensive; however, research vessels are more available than other types of ship. This paper presents the results of a time-domain simulation model of R/V Gunnerus, the research vessel of the Norwegian University of Science and Technology (NTNU), using MARINTEK’s vessel simulator (VeSim). VeSim is a time-domain simulator which solves dynamic equations of vessel motions and takes care of seakeeping and manoeuvring problems simultaneously. In addition to a set of captive and PMM tests on a scale model of Gunnerus, full-scale sea trials are carried out in both calm and harsh weather and the proposed simulation model is validated against sea trial data.Copyright

Outcomes From a Study of Validation of Ship Specific Models for Shiphandling Simulator

This paper presents some outcomes from a four years (2013 – 2016) long research project investigating validation of ship specific simulation models. In contrast to the other initiatives such as SIMMAN 2008 [1] and SIMMAN 2014 [2], the R&D project Sea Trials and Model Tests for Validation of Shiphandling Simulation Models (SIMVAL [3]) investigates model development and validation methods for specific vessels. For these vessels, the yards documentation of manoeuvring characteristic was available for the researchers. In addition, the project has been given permission to perform different sets of sea trials on selected case vessels. As far as possible, these sea trials were designed to document vessel-specific operations such as low-speed manoeuvres and dynamic positioning. Other papers presenting results from the SIMVAL project will be given in a separate session, Session 12-14, in the Torgeir Moan Symposium at OMAE2017. INTRODUCTION The Norwegian R&D project Sea Trials and Model Tests for Validation of Shiphandling Simulation Models investigated ways of validating ship-specific manoeuvring models using model tests and sea trials. Numerical models in engineering tools can be used for different purposes such as studies of ship manoeuvring characteristics in deep open waters, or the design of fairways, ports and quays. Simulation models become an integrated part of modern design tools making it possible to include manoeuvring performance as a design parameter. Numerical ship models are also used in training simulators for deck officers and pilots. The verification and validation of simulation models are closely intertwined with access to benchmark data and the accuracy of such data from model tests and sea trials. This project had access to sea trials from a number of ships. The Norwegian partners performed model tests and sea trials on five ships. The foreign partners used four other case vessels. This paper will present some of the outcomes of the Norwegian part of the SIMVAL project. The first part of this paper offers a brief overview of project content and research objectives. With reference to the findings of SIMMAN 2008 [1], we concluded that manoeuvring models used by research institutes and universities showed significant differences in their predictions of International Maritime Organisation (IMO) standard manoeuvres such as turning circles and zig-zag tests. The paper will also review the findings of efforts to develop vessel-specific simulation models for three Norwegian case vessels, one offshore vessel, one LNG coastal ferry and the research vessel of the Norwegian University of Science and Technology (NTNU). A lack of high-quality test documents from shipyards’ sea trials made it impossible to use these for validation studies of the case vessels. Following discussions with the masters of the case vessels, the project drew up vesselspecific test matrices for the collection of operational performance data required by the masters. Low-speed tests were high on their priority list. The final part of the paper discusses how the findings of the project were communicated to the industrial project partners (ship designers and shipping companies). This section also describes how results are being implemented in an operational environment for shipping companies (improved models in simulators for training and prestudies of critical operations) and design offices (design-phase simulation tools). 2 Earlier MARINTEK, SINTEF Ocean from 1st January 2017 through a merger internally in the SINTEF Group Proceedings of the ASME 2017 36th International Conference on Ocean, Offshore and Arctic Engineering OMAE2017 June 25-30, 2017, Trondheim, Norway

Maritime Operations and Emergency Preparedness in the Arctic-Competence Standards for Search and Rescue Operations Contingencies in Polar Waters

Emergencies on large passenger ships in the remote High North may lead to a mass rescue operation with a heavy strain on the emergency preparedness systems of the Arctic countries. This study focuses on the need for competencies related to large-scale Search and Rescue operations (SAR operations) amongst the shipping companies, vessels and governments involved. A SAR operation is the activity related to finding and rescuing people in distress. Several international standards, in particular the conventions by the International Maritime Organization (IMO), provide direction for education and training of seafarers and rescue staff. This study elaborates on the operational competence requirements for key personnel involved in large scale SAR operations. Findings from real SAR incidents and exercises provide in-depth understanding on the operational challenges. The chapter gives directions for competence programs, beyond obligatory international standards, and recommendations for further research.

Drifting Paths of Disabled Vessels

Many maritime emergency situations involve drifting vessels, and tools to predict drifting patterns have been developed by meteorology institutes, class societies and research companies. It is important to be able to predict a vessel’s drifting path and to estimate when it will drift into waters where grounding is a possible outcome. Such a prediction tool would provide valuable input to the planning of an emergency towing operation to prevent the vessel from grounding or to reduce the impact of the grounding.In this paper we present the outcomes of a study that investigated the drifting pattern of a vessel with an engine shut-down in the Barents Sea. As part of the ongoing A-Lex project [1], MARINTEK has prepared a VeSim [2] model to investigate the drifting path of a cargo vessel. The outcomes of the study will be used to draw up a technical specification for work to be done to develop an improved ship drift model in Norwegian Meteorological Institute’s (MET Norway’s, [3]) new Halo platform [4]. An improved model will be of great help to those planning emergency towing operations and for positioning of emergency preparedness units with respect to the traffic situation (especially tracks of vessels carrying dangerous goods) and weather forecasts.© 2015 ASME

Experimental results on motion regulation in high speed marine vessels

A design procedure of an active ride control system (RCS) for regulating the roll and pitch motions of a high speed marine vessel is presented. In order to achieve high quality passenger comfort and reduce the seasickness it is necessary to counterbalance the excessive pitch and roll motions using an active ride control system. To do so, a mathematical model of the vessel describing the motion of the high speed vessel in 3 degree of freedom, heave-roll-pitch, is derived using VERES (VEssel RESponse) program. The effect of active T-foils and interceptors is discussed, and a frequency weighted H2-optimal controller is designed and implemented. The performance of the proposed ride control system is shown by experimental tests of a scaled model of high speed catamaran in MARINTEKs ocean basin.