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 yard’s 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.acceptedVersio

Numerical assessment of a double-acting offshore vessel's performance in level ice with experimental comparison

In this paper a numerical model is used to investigate the level ice performance of a double-acting intervention vessel, and the results are compared with a limited set of experimental data. The icebreaking capability and maneuverability in level ice are analyzed by evaluating the behavior of the vessel when it is running both ahead and astern. The simulated icebreaking patterns, h–v curves, and turning circles in different modes of operation are discussed and compared partly with the corresponding ice model tests. The simulation results can supplement the experimental data by providing more information about the vessel's maneuverability in level ice and identifying the physical foundation for the exhibited performance of the vessel. The paper also presents the implementation of a random crack size model for more realistic icebreaking behavior, giving more consistent evaluation of the ship's performance in various ice conditions.acceptedVersio

Norwegian Emergency Towing Service – Past – Present and Future

The Norwegian Coastal Administration (NCA) is an agency of the Norwegian Ministry of Transport and Communications, and is responsible for services related to maritime safety, maritime infrastructure, transport planning and efficiency, and emergency response to acute pollution and drifting vessels. NCA has five regional Vessel Traffic Service centres. Of those, Vardø VTS has the special task of monitoring high-risk maritime traffic in Norwegian territorial waters, including the sea areas around Svalbard. Based on the history of ship incidents in Norwegian waters and lack of commercial tug resources in Northern Norway and the Svalbard area, the government decided in 2005 to establish a national emergency towing service. The establishment and coordination of this service was assigned to the Norwegian Coastal Administration. This paper briefly describes the development of the Norwegian Emergency Towing Service (NETS), how the service has changed over the years and plans for the coming years. Some cases involving emergency towing vessels are described. The paper also reviews the development of a national competence plan for senior officers on vessels employed by the Norwegian Emergency Towing Service.publishedVersio

Experimental and Numerical Investigation of a Double-Acting Offshore Vessel Performance in Level Ice

In this paper a numerical model and experimental data are used to investigate the level ice performance of a double-acting intervention vessel. The icebreaking capability and maneuverability in level ice are analyzed by evaluating the behavior of the vessel when it is running both ahead and astern. The paper also presents the implementation of a random crack size model for more realistic icebreaking behavior, giving more consistent evaluation of the vessel's performance in various ice conditions. The numerical simulations are firstly conducted in model-scale for a direct comparison with the experimental results. The scaling of ship speed and ice resistance is then discussed by comparing the simulation results in both full-scale and model-scale. The effect on the vessel's performance of the different properties of scaled model ice and full-scale sea ice is also assessed

Numerical assessment of a double-acting offshore vessel's performance in level ice with experimental comparison

In this paper a numerical model is used to investigate the level ice performance of a double-acting intervention vessel, and the results are compared with a limited set of experimental data. The icebreaking capability and maneuverability in level ice are analyzed by evaluating the behavior of the vessel when it is running both ahead and astern. The simulated icebreaking patterns, h–v curves, and turning circles in different modes of operation are discussed and compared partly with the corresponding ice model tests. The simulation results can supplement the experimental data by providing more information about the vessel's maneuverability in level ice and identifying the physical foundation for the exhibited performance of the vessel. The paper also presents the implementation of a random crack size model for more realistic icebreaking behavior, giving more consistent evaluation of the ship's performance in various ice conditions

Norwegian Emergency Towing Service – Past – Present and Future

The Norwegian Coastal Administration (NCA) is an agency of the Norwegian Ministry of Transport and Communications, and is responsible for services related to maritime safety, maritime infrastructure, transport planning and efficiency, and emergency response to acute pollution and drifting vessels. NCA has five regional Vessel Traffic Service centres. Of those, Vardø VTS has the special task of monitoring high-risk maritime traffic in Norwegian territorial waters, including the sea areas around Svalbard. Based on the history of ship incidents in Norwegian waters and lack of commercial tug resources in Northern Norway and the Svalbard area, the government decided in 2005 to establish a national emergency towing service. The establishment and coordination of this service was assigned to the Norwegian Coastal Administration. This paper briefly describes the development of the Norwegian Emergency Towing Service (NETS), how the service has changed over the years and plans for the coming years. Some cases involving emergency towing vessels are described. The paper also reviews the development of a national competence plan for senior officers on vessels employed by the Norwegian Emergency Towing Service

Manoeuvring Study – Norwegian Double-Ended Ferry

The Norwegian coastline has many long fjords where crossings are necessary for transportation of goods and passengers. In the last decade, the focus on reduced travel time along the main roads in coastal areas has increased the building of bridges and subsea tunnels. However, at present and in the future many fjord crossings will depend on ferries. The Norwegian government [7] requires that ferries, like all coastal ships in Norwegian waters, should be designed for zero or low greenhouse gas (GHG) emissions to meet the national goal of 50% reduction of GHG from coastal shipping by 2030. As ferry services are regulated by national or local governmental bodies, all new ferry operations should be performed using zero- or low-emission ferries. Thus, ferry companies require new and innovative ferry designs with reduced resistance, resulting in reduced installed propulsion power. This paper describes work done by the ship designer HAV Design AS (former Havyard Design & Solutions AS (HDS)) to meet the governmental request for ferries with a low environmental footprint. Work on a double-ended ferry design is described. In the early design phase manoeuvring performance is not a priority item, partly due to lack of a simple and reliable manoeuvring performance prediction tool for unconventional ship designs. It is well known that optimization of resistance can be at the cost of manoeuvring performance. In this paper, a specific double-ended ferry design will be used as a case. Outcomes of design simulation of manoeuvring performance are compared to manoeuvring full-scale tests in deep, calm water. Full-scale test results will later be used to tune a simulation model for a future training simulator for double-ended ferry, where full-scale manoeuvring tests have been performed, will be used as a test case. This paper shows how the designer has worked with these two topics in parallel in the final design stage where both experimental and numerical tools have been used for design verification