Highlights.Issue 67/2020

Page 2 – 3 Page 4 – 5 Page 6 – 7

Page 8 – 9 Page 10 –11 Page 12 –13

Heading towards 2030Working towards customers who take a long-term holistic approach to their maritime systems.

GreenPilotGuiding the way to low -emission and fossil-free operation of small vessels. Renewable metha-nol fuel tested on a pilot boat.

The use and usefulnessof AIS dataAIS data show great promise for innovative R&D projects and commercial tools.

Hull structural dynamicsDeveloping knowledge and accurate model testing technique. Insights to support new areas.

SEAMAN OnlineTaking availability and flexibility to the next level. First web-based professional maritime manoeuv-ring training simulator. .

Oil spill risks in ArcticRisk assessment methodology to estimate credible scenarios for design of adequate response capacity.

A renaissance of wind-powered shipsWith IMO’s newly adopted strategy for cutting greenhouse gas emissions by at least 50 percent in the next thirty years, the international shipping industry is in for some radical changes. SSPA has developed efficient prediction tools for both wind-driven and wind- assisted ships in order to support the development of more sustainable maritime transports.

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2 Highlights 67 / 2020 – Heading towards 2030

Today, nobody can avoid discussions about climate change and how to develop a sustainable society, how this will affect us and what we can do to avoid the conse- quences. These discussions take place at all levels of society, from top-level UN meetings to kitchen table meetings. I think we all know that we need to make changes, but we are still questioning what should be done and by whom. The UN has taken leadership in this area by establishing the 17 Sustainable Development Goals (SDG), where they point out where and how the world must change if we want to avoid poverty, inequality and environmental damage.

The maritime sector is of course also affected by this discussion, since it conducts business worldwide that is relevant to several of the 17 SDGs, and as for the rest of the world, there are no clear answers as to what the best solution is for meeting the goals and satisfying other requirements. In particular, the question of how to reduce emissions does not have a clear answer at present. There are several options, but they have different positive and negative consequences, and different investment costs connected to them. This means that system owners run a high risk of choosing a solution that will not meet the target for the investment.

To be able to satisfy the requirement to reduce greenhouse gas emissions by 50 percent by 2050, you will most likely need to combine different actions for your system, such as a change of fuel, a new propulsion method, different material and construction, improved operations, etc.

In this edition of Highlights, we have several articles describing different actions that should be possible to reduce green-house gas emissions, directly or indirectly. Personally, I am very interested in following the development concerning using sails as a propulsion method once again, and as such I would recommend reading the article “A renaissance of wind-powered ships” on page 14.

I hope that you find some articles to pique your interest. Happy reading!

Stefan EliassonPresident & CEO

Highlights.SSPA’s vision is to be recognised as the most rewarding partner for innovative and sustainable maritime development. We want to contribute with new solutions to be able to achieve a long-term sustainable and environmentally friendly society for both those of us who live here today and for future generations.

Heading towards 2030

Our vision is based on the fact we have just one Earth and therefore we must take care of the one we have so it will also be a good place to live for future generations. This is not in any way a unique insight; we share it with many people and organisations around the world. There is an increasing awareness that we need to act on this insight. Therefore, one of the strongest global trends today is how to work with the issues regarding sustainability. This awareness has now reached such a level that nobody can avoid these issues any more. Society expects companies and organisations to declare how they are contribu-ting to a better and more sustainable society and if they are not considered to be doing enough, they risk attracting bad will.

Sometimes a trend is just a trend, i.e. it occurs for just a short period of time and does not change the way we live in a profound way. But sometimes trends last and do affect our lives. One way to test whether this will be a short-term trend or not, is to use the “follow the money” principle. If (big) money is invested in certain trends, you can be assured that this is for real and it will last. Today there is an increasing amount of money invested in sustainability projects, which indicates that this will be a trend that lasts. This change has not only happened because investors are following this global trend, but

also because they believe that sustainable and green investments will outperform conventional investments in the long term.

Larry Fink, CEO of Blackrock, one of the world’s largest investment management companies with approximately $7 trillion in managed capital and therefore one of the world’s largest investors, is clear in what he believes will determine whether a company will prosper or not.

“To prosper over time, every company must not only deliver financial performance, but also show how it makes a positive contribution to society.”

So, sustainability issues have clearly moved into the boardrooms of companies and organisations and are current key talking points.

Sustainable development goalsTherefore, many countries, organisations and companies now have clear ambitions and goals for their sustainability work. The United Nations (UN) has been clearest in this ambition with the most ambitious agenda for sustainable development ever adopted. They have defined an overall target by 2030 to eliminate poverty, reduce inequality and injustices, promote peace and solve the cli-mate c risis, and from this overall target they have defined 17 Sustainable Development Goals (SDG).

Of course, one can discuss the realism of achieving these goals within the short timetable set and if there will be enough investment capital avail able to meet the need. But just the fact that the UN has addressed these issues will mean that a lar-ge part of the world will focus on this in the coming years and make their contribution to fulfil them.

Maritime industry has special challengesThe maritime industry is, of course, also influenced by this development to achieve a more sustainable environment and to contribute to the 17 goals. But besides this, the IMO has implemented requirements for the maritime industry that will radically reduce air emissions over the next 30 years and especially the target to reduce carbon dioxide emissions by half in 2050. That will be a great challenge to meet!

“We want to get in early in the decision-making process so that we can positively influence the

decisions that are most important for the long-term outcome.”

Stefan EliassonPresident & CEO

Stefan has been President at SSPA since 2018. Before that, he was the Chairman of the Board

between 2013 and 2018. Prior to SSPA, Stefan was Managing Director of MMT Sweden for five years, a survey offshore company revealing the sea bottom for the offshore industry, and Managing Director of Transatlantic, a shipowing company listed on the Stockholm Stock Exchange. Stefan was also responsible for Transatlantic’s Offshore/Breaking division for many years and worked together with SSPA to develop an ice simulator. He has also served as a Board member of the Swedish Shipowner Association and as a Board member of a ship financing company.

Contact information E-mail: stefan.eliasson@sspa.se

The challenge lies in the fact that there are currently no obvious solutions that both meet the requirements and that are socially, operationally or financially sustainable in the long term. So, there is a great demand for technological and operational innovations to be able to solve this.

But innovations will not be enough. In order to achieve the goals, it is likely that people will need to assume that they must look at their entire operational system and implement a variety of smaller and larger innovations and improve-ments in order to be able to reach the target 30 years from now. To be able to do this, it will be necessary to look at the maritime system long-term and holistically when choosing a solution. This is especially important for the maritime industry, with its long investment horizon. There will not be one quick fix here; it will be more like a package of different solutions that add up to the target.

And even if it seems that 2050 is far away, time is running out. The vessels that are designed are expected to still be in operation in 2050, so they should at least theoretically be part of the plan for reduced emissions. In such a situation, it is obvious that there will be a high risk of selec-ting a solution that will not meet the objectives. This means a new moment is added to the risk calculation for your investments, the risk that the investment will not be sustainable or meet future requirements. Risk analysis and assessments regarding sustainable solutions will therefore have a greater importance and impact on your investment decisions than before.

SSPA’s mission is right on timeWe at SSPA think that the development towards a long-term sustainable society is exciting, because it is in line with how we want to work to help our customers and partners to be successful.

This is stated in our vision which is our WHY “to be recognised as the most rewarding partner for innovative and sustainable maritime develop-ment”, and our mission which is our HOW “to work towards customers who take a long-term holistic approach to their maritime systems”.

So therefore, it is very natural for us to take part in this challenge to fulfil the different sustainabil- ity objectives that the UN and other organisations have introduced and to help our customers create sustainable value. The key words for us will be to see everything in a holistic context and over the full lifetime of the investment, and from that per-spective find solutions that meet customer objec- tives and with a high probability of succeeding.

This is a challenge that suits SSPA’s attitude and competence – finding solutions that create long-term value for customers. We have extensive expertise in different areas that will be needed to

understand what solutions are available and which will be the optimal and creating long-term value for customers. We will also look at the entire value chain, from design, construction, operation etc., and combine methods and innovations in new ways in order to achieve the required result.

Therefore, a large part of our development efforts in the coming years will be geared towards developing new methods and systems for a sustainable maritime society.

SSPA is a company that wants to give good advice and recommendations that will create long-term value for our customers. But to be able to do that, we want to get in early in the decision- making process so that we can positively influence the decisions that are most important for the long-term outcome. A general rule of thumb is that 80% of the consistency of a system’s lifelong costs already arises during the exploration and design phase of the project. This means that once you have entered the construction phase, it is difficult to reduce the costs and environmental impact that much. Again, the holistic perspective and lifelong perspective is important to have in order to achieve optimised results.

There is a Swedish proverb that says that “right now good advice is expensive”, which is used when faced with major uncertain decisions but where time is short. SSPA wants to be the one to come up with good advice at the right time, but without being expensive. In any case,

we will be there for our customers to guide them through difficult times ahead and we will constantly develop our capability to do so, with new knowledge and methods.

Follow us into the future – it will be exciting!

SSPA supports the Sustainable Development Goals.

4 Highlights 67 / 2020 – GreenPilot – guiding the way to low-emission and fossil-free operation of small vessels

GreenPilot – guiding the way to low-emission and fossil-free operation of small vessels

Reducing emissions to meet climate goalsThe developing climate crisis has led to the establishment of targets both internationally and nationally to reduce emissions of greenhouse gases. The International Maritime Organization (IMO) adopted a strategy in 2018 that calls for greenhouse gas (GHG) emissions from shipping to be reduced by at least 50 percent by 2050 (compared to 2008 levels).

In Sweden, the government has set an ambitious goal of net zero emissions by 2045, and this is shared by the Swedish Transport Administration’s road ferries. Swedish transport emissions should be reduced by 70 percent by 2030. The Swedish Maritime Administra-tion, another partner in the GreenPilot project consortium, has a vision for a zero-emission pilot boat, and this was a starting point for the project.

The GreenPilot project converted a pilot boat to operate on renewable methanol fuel, demonstrating the improvements to environmental and operational performance that can be achieved for this fuel. Methanol is a clean-burning alcohol that does not contain sulphur and results in low emissions of particulates and nitrogen oxides when combusted. It can be produced from many renewable feedstocks, which means that “well to wake” greenhouse gas emissions can be significantly lower than those of fossil fuels.

Why methanol?Methanol is a liquid fuel that can be easily stored and bunkered on smaller vessels and it can be produced from many renewable feedstocks.

It has been used successfully on a few large vessels, including the Stena Germanica, where it demonstrated good performance in a dual-fuel medium speed engine application. Although there are currently no commercially available small marine engines (300 – 1,200 kW power range) that are approved for operation on methanol, development and testing of different methanol concepts for engines in this range were carried out in the SUMMETH (Sustainable Marine Methanol) project, which included many of the same partners as GreenPilot. The GreenPilot project was the first to test methanol on board a smaller vessel with a high-speed engine.

The GreenPilot project showed that it is feasible to convert small vessels to methanol operation.

Mr Freddy Debue and Mr Louis Vervloet from the Port of Antwerp visiting the GreenPilot boat in October 2019.

Photo: ScandiNAOS

Pho

to: J

oann

e E

llis.

into service in 2016. In October, Stena Bulk and Proman announced plans for a joint venture to own and operate methanol- fuelled tankers.

In the smaller vessel segment, significant interest exists but there are no vessels in regular operation. The Port of Antwerp carried out a feasibility study on converting a tugboat to methanol operation and visited the GreenPilot boat in October 2019.

The Inland Waterways Authority of India has announced plans to build methanol-fuelled boats and cargo vessels to reduce emissions and use a nationally produced fuel – methanol made from fossil feedstocks and from municipal solid waste.

ScandiNAOS has continued testing a

Joanne EllisSenior Researcher and Project Manager.

Joanne has a PhD from Chalmers University of Technology and an MASc in Environmental

Engineering from the University of British Columbia. Since joining SSPA in 1999, she has been involved in projects in the areas of risk, safety, alternative marine fuels, and environmental assessment of marine transport. She has managed and participated in several projects on the use of methanol as marine fuel, including serving as project manager and lead author of a study for the European Maritime Safety Agency, and coordinating multi-partner research projects.

Contact information E-mail: joanne.ellis@sspa.se

Comparison of greenhouse gas emissions for the annual pilot boat fleet operation using ma-rine gas oil (MGO) and methanol produced via pulp mill black liquor gasification (BLG).

Emissions from methanol combustion as compared to MGO baseline. MGO shown as 100%. Note that the emissions values are per MJ of fuel. Particulate matter (PM) emissions are shown as mg.

01.0002.0003.0004.0005.0006.0007.0008.0009.000

10.000

MGO Methanol (BLG)

Well to Tank Tank to Propeller

WTP GHG Emissions as tonnes CO2 eq per year

0%

20%

40%

60%

80%

100%

NOx

0.52 g/MJ

0.18 g/MJ

0 g/MJ 0.003 g/MJ

0.23 g/MJ 12 mg/MJ

SOx PM

MGO Methanol

Emissions from methanol combustion as compared to MGO baseline

– MGO shown as 100%

Illustrations by SSPA.

compression ignition concept engine on the GreenPilot test boat and has tested both methanol and ethanol fuel in the same engine. Both alcohol fuels performed well.

The GreenPilot project showed that it is feasible to convert small vessels to methanol operation. The demonstration of bio-methanol as a low emission, low environmental impact fuel on a pilot boat was a great initiative for this vessel segment.

SSPA is committed to developing sustainable solutions for shipping and was proud to be part of the GreenPilot project team.

The GreenPilot project consortium c onsisted of the Swedish Maritime Technology Forum at RISE, ScandiNAOS, SSPA Sweden, Swedish Transport Administration, and the Swedish Maritime Administration. The project was co-funded by the Swedish Transport Administration, the Swedish Maritime Administration, and the Methanol Institute.

Converting a pilot boat to methanol operationThe two-year GreenPilot project began in 2016, with a main goal of converting a 12.6-metre long pilot boat that was made available to the project by the Swedish Maritime Administration.

The conversion work involved adapting on-board systems, primarily fuel supply and safety, and replacing one of the vessel’s two main engines with an engine converted to methanol operation. Two engines, a Weichai and a Scania SI, were converted by project partner ScandiNAOS to run on methanol using spark- ignited port injection technology. Both engines were tested on land and on the pilot boat.

A compression ignition engine was also tested on land during the later stages of the project and was tested post-project in the pilot boat.

Testing on boardRenewable, fossil-free methanol produced from pulp mill black liquor in a Swedish pilot plant was used in many of the tests. Engine efficiency was tested under real driving conditions, and emissions were measured both in lab testing and on board the vessel.

Diesel-like performance was observed during the testing, with high efficiencies ranging from 37–40 percent. Emissions measurements taken on board included nitrogen oxides (NOx), parti-culate matter (PM) and particulate number (PN) taken by Chalmers University. SOx was mea-sured during laboratory testing. PM emissions were extremely low, as alcohol fuels do not form soot. NOx formation was reduced as compared to MGO operation, and the emissions from methanol combustion complied with existing and upcoming IMO and EU (Inland Waterway Euro V) regulations.

Good environmental performance with renewable methanolEnvironmental performance assessment was focused on comparing air emissions on a fuel life cycle basis. The fuel life cycle comparison included emissions both from fuel production, “well to tank”, and fuel combustion on board, “tank to propeller”. Greenhouse gas emissions (GHG) reductions over the fuel life cycle in the range of 94 percent were achieved for methanol produced from pulp mill black liquor (the bio-methanol used in the testing).

Interest in methanol fuel continues to growDuring 2019, more large vessels operating on methanol have entered regular service. Waterfront Shipping added four more dual-fuel methanol tankers to its existing fleet of seven that came

6 Highlights 67 / 2020 – The use and usefulness of AIS data

What is AIS?The Automatic Identification System (AIS) has been in full operation for around fifteen years. It is an automatic nautical tracking system on board ships that gathers and provides ship information to other ships and shore organisa-tions such as the Vessel Traffic Services (VTS). It assists ships and maritime authorities to identify and monitor ships’ movements.

AIS includes the ship’s identification number, position, course, speed, type of cargo, among other ship and voyage specificities. This information is typically displayed on the Electronic Chart Display and Information System (ECDIS) screens in complement to the marine radar, which is still the primary tool on board for collision avoidance during voyage execution.

The transfer of AIS information is done via AIS transponders on board ships in connection with satellites. AIS transponders integrate electronic sensors such as a Global Positioning System (GPS), a Very High Frequency (VHF) transceiver, a rate of turn indicator and a gyro - compass, to capture up-to-date ship statuses such as rate of turn and geographical direction.

According to the International Maritime Organization’s (IMO) convention for Safety of Life at Sea (SOLAS), vessels over 300 gross tonnage are obliged to be equipped with an AIS transponder, class A, that can transmit and receive all message types.

In what contexts are AIS data useful? There are AIS base stations located along coastlines that can receive and record a large amount of AIS data. Beyond the original purpose of AIS, having access to AIS records also opens up unique possibilities in research and develop-ment projects (alone or combined with other datasources). They enable learning about shipping patterns and integrating them into optimisation models or simulations, new services and applica-tions, and thereby helping to reduce uncertainty.

SSPA’s researchers have identified that there are at least ten different research areas in which

The use and usefulness of AIS dataAIS data have been used in various research areas in the maritime domain beyond its intended and practical purpose of providing ship information during voyage execution. It offers the possibility to understand historical and typical ship behaviour, as well as generate real-time decision-support solutions for mariners and shore-based operators. SSPA has engaged in various research and development projects using AIS data as their basis, and even offers important and novel commercial tools that function via algorithmic analyses of historical and real-time AIS data.

AIS data are used today:• traffic (e.g., mapping ships’ routes);• logistics and transport economy (e.g.,

traffic between ports, delays and trade);• monitoring (e.g., abnormal ship behaviour);• collisions and navigational safety (e.g.,

probability of accidents);• emissions (e.g., air emissions from

ships’ movements);• oil spills (e.g., mapping and monitoring

marine oil pollution);• noise (e.g., the relationship between

noise and underwater fauna);• interaction with whales (e.g.,

distribution of blue whales in relation to current shipping lanes);

• fishing (e.g., density mapping and fishing vessel movements), and

• ice (e.g., navigation and performance in ice).

Within these areas, AIS data can benefit actors within the IMO, maritime administrations, national and local authorities, the VTS, shipping companies, governments, fourth-party logistics companies, ports, coastguards and military, as well as various industrial stakeholders and actors associated with maritime infrastructures, shipment and wildlife.

AIS data-based research, development and innovationSSPA has stored years of AIS data, both from Swedish coastal waters by the Swedish Maritime Administration (SMA), and from across Europe via the crowd sourcing initiative AIS Hub. At SSPA, we also have the ability to load any AIS data in NMEA format for customer-specific analysis.

The regional project, MariA – Maritima Analyser, funded by Interreg Öresund-Katte-gat-Skagerrak, is one of the platforms where SSPA has performed several AIS data-based studies. SSPA’s researchers have, for example, revisited the concept of “ship domain” (distance to other ships/land), based on AIS data analy-sis. They concluded that the characteristics of different waters and the type of ship intersections

influence the shape and size of the ship domain.Another example concerned the study of the

Gothenburg container port conflict, between port operators and a labour union in 2016–2017, and how traffic and goods flows were affected, by using a combination of official port statistics and AIS data. Results showed that Gothenburg suffered a large decline in productivity and in the total number of containers handled, whereas the other ports in Sweden were only partly able to handle their increased volumes. Instead, there was a significant environmental impact as trucks had to bring containers to and from European ports.

Other AIS data analyses have been performed at SSPA, such as those in the FAMOS Odin project (closed in June 2019) for route optimisation analysis and investigation of common under-keel clearance (UKC) distances in the Baltic Sea. Read more about these projects in Highlights 66.

Commercial applications of AIS dataAIS data also form the basis of commercial developments at SSPA since 2016, primarily within SSPA’s service area dealing with Environ-ment, Risk and Operations. When combined with SSPA’s extensive knowledge of the hydro dynamic fundamentals of ships, it is possible to produce

MariA is a research project (2017–2020) co-funded by Interreg ÖKS and the European Regional Develop-

ment Fund, coordinated by SSPA, in partnership with the Danish Maritime Authority. The aim is to develop and test improved maritime data analysis methods and tools to reduce shipping accidents, the environmental footprint and maritime infrastructure costs, and increase the accessibility of shipping compared to road-based transport.

Nicole CostaSenior Researcher in Maritime Human Factors and Project Manager.

Nicole has a PhD in Human Factors from the depart-

ment of Mechanics and Maritime Sciences at Chalmers University of Technology and an MSc in Organisational and Social Psychology from ISCTE-IUL, Portugal. She started at SSPA in 2018 and has been involved in European, regional and in-house digitalisation projects.

Contact information E-mail: nicole.costa@sspa.se

Martin SvanbergSenior Researcher in Logistics and Project Manager.

Martin has an MSc in Mechanical Engineering and a PhD in Technology Management and Economics. He has conducted research in logistics since 2009. He joined SSPA in 2015 and has been involved in projects about logistics, goods flows and AIS analyses.

Contact information E-mail: martin.svanberg@sspa.se

Axel HörtebornSpecialist, Simulations & Risk analyses

Axel has an MSc in Risk Management and Safety Engineering. He uses

Geographical Information Systems (GIS) and big data analyses in constructing risk assessment models and has worked with the Norwegian Public Road Administration (NPRA) investigating risk of bridge collapse due to ship collisions. Since 2017, he has also performed research work on ship failures and how they influence design criteria for maritime infrastructure.

Contact information E-mail: axel.horteborn@sspa.se

Fredrik Olsson Specialist, Simulations & Algorithms – Core Developer

Fredrik has an MSc in Naval Architecture from

Chalmers University of Technology. He is in charge of the development and maintenance of SSPA’s simulation tools. He also coordinates and maintains the software development infrastructure.

Contact information E-mail: fredrik.olsson@sspa.se

operational and environmental analyses both at an aggregated and individual level, supplying information and decision support to ship operators and environmental and maritime authorities.

AIS data are also a powerful tool in establish-ing risk scenarios for ship-to-ship and ship-to-shore collisions and groundings, for instance in the Björnafjord project. AIS data from the relevant geographical area were fundamental in establishing a basis for the Monte Carlo simula-tions performed. Read more in Highlights 60.

SSPA’s Automated Behaviour Monito-ring (ABM) tool is another example of the commercial applications of AIS data. The ABM tool uses big data analyses and simple Artificial Intelligence (AI) functionality to i dentify abnormal behaviour of ships operating in a specific area. This can be used to establish early warning systems of potential maritime accidents to initiate evasive manoeuvres and emergency response activities before a serious maritime accident occurs.

The future of AISFor future research, it is proposed that AIS data could be useful in studies about the spread of marine litter, shallow water effects, fuel consumption, the fill rate of cargo ships, or how political and historical events such as Brexit affect maritime traffic. Continuous research on the technical challenges of AIS is also recom-mended, e.g. its coverage issues and bandwidth, security and reliability.

Past research has shown that AIS is gener-ally perceived by ship officers as an important aid in improving their situational awareness. Yet, statistically, it is not clear that it has had a significantly positive impact on the number of collisions. Especially during the infancy of AIS, there were AIS stations transmitting erroneous data, and although it is believed that this has

improved over time, ship officers and shore operators still report being cautious with trusting AIS information.

In some parts of the world, the AIS commu-nication link is reaching its capacity limit. At the same time, there is a will to introduce new func-tionality and to extend the type of information sent over AIS. A potential new standard under develop-ment is VHF Data Exchange System (VDES), which utilises both terrestrial and satellite radio communication in the VHF maritime mobile band. It allows for ship-to-ship, ship-to-shore and ship-to-satellite communication. The bandwidth should be roughly 32 times higher than today.

Newly proposed functionality to be added, mainly related to IMO’s e-Navigation initiative, is ship-to-ship and ship-to-shore route exchange, exchange of port information and adjustment of Estimated Times of Arrival (ETAs), exchange of weather and ice data, improved information exchange in Search and Rescue (SAR), update of electronic charts, and receival of navigational warnings directly into the ECDIS.

Within the Sea Traffic Management (STM) project, interviews performed by SSPA with various operators identified, however, that they reckon instead that the reliability and proper display of functions already available today are a more urgent matter. SSPA has also done work in this direction within the EfficienSea projects, having developed and demonstrated methods for automatic surveillance of AIS data quality.

The usage of AIS/VDES data in algorithm development, decision-support and automated systems on board and ashore, should also be subject to user and interaction studies to assess user needs, trust, increased automation and its impact on operations.

References are available at www.sspa.se/the-use-and-usefulness-of-AIS-data

SSPA’s Automated Behaviour Monitoring (ABM) tool interface, where red triangles represent ships with an abnormal course for that area.

© SSPA Sweden AB© OpenStreetMap contributors

8 Highlights 67 / 2020 – Tailored model tests for hull structural dynamics

Tailored model tests for hull structural dynamicsIn the trend towards more efficient transport, energy-efficient operation and reduced environmental impact at sea, ship hulls tend to increase in size (OECD 2015*). With the increase in ship size there is also an increased risk of hull structural resonance being excited by waves and for instance slamming loads, as well as significant hull bending in large and long waves. This also holds for ships that utilise novel hull design principles, such as lightweight designs, novel hull forms, hulls with alternative weight distribution etc. SSPA has developed techniques for analysis of ship hull structural dynamics over several years, i.e. analysis of the structural response due to wind and wave loads. We decided to share this information and join forces with several partners to develop knowledge, and a new research project was formed and led by SSPA. This resulted in an accurate model testing technique, know-how to carry out this kind of model testing and insights into possibilities to develop further important techniques to support this important area of technology.

Illustration of influence of optimal hull structural design on costs.

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SSPA’s commitment started as internal development with internal funding. In this initial stage, much valuable knowledge and many valuable techniques were developed, while it was also recognised that an effort was needed on a larger scale to drive and support the development of efficient sea transport in terms of energy consumption, e conomics and alternative propulsion.

Overdimensioned or undersized vesselsExperience from ship operations with large vessels shows that today’s regulations, methods and tools are not fully able to take into account the structural characteristics of a number of today’s more optimised types of vessels. These vessels differ from previous designs in that structural dynamics account for a large propor-tion of the total load on the vessel. Structural dynamics is also often i dentified as the most

significant weakness of today’s methods, tools and regulations for hull scantling.

This means that an increasing proportion of vessels are not optimally dimensioned for their transport task. Of these, many become over dimensioned and have increased energy consumption and life cycle costs as a result. Others become undersized with insufficient safety margins, which also leads to increased need for maintenance and high costs but has also in some cases resulted in breakdowns even with relatively new vessels. As a result, classification rules based on quasi-static hull l oads have been updated in recent years to reduce the risk of accidents.

Vessels optimised for alternative propulsionsIn addition to increasing ship size, the de-mand for hulls suitable for alternative means of propulsion is increasing. To strengthen the

An artist’s rendering of the future Stena Elektra together with a rendering of the CAD drawing of the scale model and a picture of the structural dynamic model as-built by SSPA.

Photo: Courtesy of Stena.

*OECD-Report - Merk, O. (2015) “The impact of Mega-Ships”.

development of ships propelled partly or entirely by alternatives such as batteries and wind, it is important to improve tools for structural design to provide possibilities to implement hulls optimised

Illustrations by SSPA.

Olov LundbäckSpecialist, Simulations & Algorithms.

Since joining SSPA in 2016, Olov has been involved in projects in the

areas of ship motion simulations, battery hybrid propulsion, seabed erosion and marine operations. Prior to joining SSPA, he has worked with solid mechanics and hydrodyna-mics within subsea infrastructure for the oil and gas industry, engine development at Scania and at Westcon Group. He has a PhD in ship dynamics from Chalmers University of Technology and an MSc in Naval Architecture from the Royal Institute of Technology.

Contact information E-mail: olov.lundback@sspa.se

Jonny NisbetSenior Specialist, Submersibles.

Jonny received his MSc in Naval Architecture from the Chalmers University of

Technology in 1989 and his PhD in Ther-mo-Fluid Dynamics from Chalmers in 1994. He has worked for SSPA since 2009, except for one year spent on research and consultan-cy projects related to manoeuvring and seakeeping. He specialises in submarine hydrodynamics, model testing and the simulation of manoeuvring performance.

Contact information E-mail: jonny.nisbet@sspa.se

Time history of midship bending moment from a test run with the Stena Elektra model.

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Trigging hull resonance frequency

Slowly decreasing influence of dynamics

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Large influence of structural dynamics

Accurate test setup verified against calculated still water bending moment.

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by such means of propulsion. For example, a hull that is to host a large and heavy battery pack will need a novel hull and structural design to carry loads from batteries, provide the right stability and right roll periods for good comfort. It also provides the option to distribute weight to cancel out still water bending moments in order to decrease loads and enable a lighter more optimised hull.

Wind-assisted propulsion also offers challenges and possibilities that require improved knowledge on hull scantling and hull structural dynamics.

Collaboration to develop knowledgeStena has been involved in the development of techniques to evaluate hull structural dynamics in a collaboration between SSPA, Chalmers University of Technology and the Royal Institute of Technology (KTH). Stena plans to have scaled up operation of electrically propelled vessels by 2030. A research project with the partners above was formed and led by SSPA. This project was granted funding from the research portfolio of the Swedish Transport Administration.

Tests with Stena ElektraSSPA has tested a hull of Stena Elektra with the correct model scale stiffness for a hull with room for a flexible layout and a lightweight hull with energy-efficient hull lines to make battery propulsion feasible.

This joint effort was carried out in a project where a model testing technique was developed together with computations by state-of-the-art hydrodynamic simulations, FE-tools and analytical calculations.

There were several technical challenges to overcome to be able to build a scale model with the right properties in terms of structural dynamics. To provide room for correct mass distribution and stiffness, the model was, to a large extent, built in carbon fibre and aluminium. The model was designed to capture the most important modes of hull vibration. A design divided into four sections was developed and prepared with adjustable stiffness, the appropriate amount of structural damping and thin membranes of latex. The section cuts required a completely dry environment to be able to have very accurate high resolution transdu-cers. The model design and construction are shown on page 8. Measurement accuracy was verified by, for example, a comparison between calculated and measured bending moment in still water as shown in the illustration below.

A few of the principles of ship structural dynamics are shown above which display a time series of the measurements of midship hull bending moment on the Stena Elektra hull. In this figure, an initial period of bending moment response entirely in pace with the wave encoun-ter frequency can be seen.

A second phase with a lot of hull resonance trig-gered by somewhat larger waves can also be noted. After that a period of slow decay in the resonant bending moment is displayed. A ship hull normally

has a very low structural damping, which results in slowly decaying hull girder vibrations once started.

Results of high valueIn addition to the model tests, simulations were performed which showed that simulations can be useful for understanding principles and studying the influence of different design parameters. It was also apparent that simulation techniques need further refinement to give high quality results. This study also showed that model tests with high quality measurements are a very powerful tool in combination with simulations to generate high value results for the development of new ships, also in the area of hull scantling and hull structural dynamics.

Building up of knowledge to support SSPA aims to continue joint research efforts and knowledge-sharing to continue to be a driving part of the build-up of knowledge to support commercial partners, regulatory bodies and the transportation business as a whole.

10 Highlights 67 / 2020 – SEAMAN Online – taking availability and flexibility to the next level

Anywhere, anytimeIn contrast to other ship manoeuvring training tools, SEAMAN OnlineTM is a fully web- based tool provided as a Software as a Service (SaaS). This adds significant flexibility as well as reduces costs for anyone who needs to train or evaluate ship manoeuvring in confined spaces in varying conditions.

The only thing needed to access SEAMAN Online is a reasonably modern computer and internet connection to perform or evaluate exercises on board, at the office, at school, at the library, or at home.

Based on 80 years of experienceSEAMAN Online uses the same core as all other simulation-related services provided by SSPA. The core is based on 80 years of ship hydrodynamics testing, research and development, as well as 50 years of maritime simulation activities. This vouches for a high level of accuracy of the ship movements when training in SEAMAN Online.

SEAMAN Online is capable of handling vari-ous hydrodynamic effects, such as bank and squat effects, shallow water effects and ship-to-ship interactions, as well as different weather- related forces generated from wind and current.

SEAMAN Online – taking availability andflexibility to the next levelThe phrase “Repetitio est mater studiorum” or “Repetition is the mother of learning” was the starting point for the SEAMAN Online™ development. Requested by clients who wanted to provide their staff or students with unlimited access to a manoeuvring training environment, SEAMAN Online is the world’s first web-based professional maritime manoeuvring training simulator, taking availability and flexibility to the next level.

It also includes the ability to perform tug- and mooring rope-assisted manoeuvres.

The tool’s interface includes a conning display based on the outcome of the EU- funded CyClaDes project and a bird’s eye 2D visualisation of the Electronic Navigational Charts (ENCs) in line with the International Hydrographic Organization’s (IHO) S-52 standard. This provides an interface familiar to most maritime students and professionals.

Standard and customisedDepending on the needs of the user, it is possible to provide everything from generic training vessels and environments to bespoke ships and port models through the tool. This implies that the tool can be adopted to suit various types of maritime organisations, such as shipowners, maritime training facilities, ports, consultants, etc.

Chalmers University of TechnologyChalmers University of Technology has, for a long time, used simulation solutions supplied by SSPA. These have been software-based tools installed on computers in specific simulator rooms. To use these tools, the students have had to book a timeslot beforehand during periods where the availability has been poor.

When a need to replace the old simulation solutions was identified by Chalmers, the idea of making it a web-based tool emerged. Based on this, SEAMAN Online was developed.

A first version was made available to Chalmers by mid-2018, and the first course it was used in was the compulsory “Ship handling and navigation in confined waters”, where all students were given a login and access to several tailor-made exercises.

“The introduction of SEAMAN Online into our Master Mariner programme has really increased the availability of a ship manoeuvring training environment for our students. No need to book a specific simulator room or computer anymore, just log in when you have the time. Despite this, I can still, as a teacher, evaluate the ability of each student and provide feedback and support through the tool.”

Capt. Reto Weber, Lecturer, Chalmers University of Technology

Left: the simulation interface. Right: the evaluation interface. SEAMAN OnlineTM is the first web-based professional maritime manoeuvring training simulator.

Illustration by SSPA.

Johan AlgellSenior Naval Architect, Maritime Sales.

Johan graduated with an MSc in Naval Architecture from

Chalmers University of Technology in 1997. He was also awarded an Exec. MBA in Shipping and Logistics from the Copenhagen Business School in 2003. With a multifaceted career within shipping and ship design, he joined SSPA in September 2015.

Contact information E-mail: johan.algell@sspa.se

Fredrik OlssonSpecialist, Simulations & Algorithms – Core Developer.

Fredrik has an MSc in Naval Architecture from

Chalmers University of Technology. After graduation, he worked with offshore installations at Technip Norway, participa-ting in the preparation and operational phases of the Snøhvit field. After joining SSPA in 2015, he is now in charge of the development and maintenance of SSPA’s simulation tools. He also coordinates and maintains the software development infrastructure.

Contact information E-mail: fredrik.olsson@sspa.se

Nicole CostaSenior Researcher in Maritime Human Factors and Project Manager.

Nicole has a PhD in Human Factors from the

department of Mechanics and Maritime Sciences at Chalmers University of Technology. She previously specialised in Organisational and Social Psychology at ISCTE-IUL in Lisbon, Portugal. She has been involved in a number of European research projects investigating maritime navigation technology, automation and human-centred design practice from a human factors’ perspective. Since starting at SSPA in September 2018, Nicole has contributed to European, regional and in-house maritime digitalisation projects.

Contact information E-mail: nicole.costa@sspa.seSEAMAN OnlineTM is a fully web-based tool. Perform or evaluate exercises on board, at the office,

at school, at the library, or at home.

“In my profession as a Master Mariner, I have used SSPA’s simulation capabi-lities for a long time. SEAMAN Online is an attractive extension of their servi-ces and I use it regularly both to train and test different scenarios myself and to support and teach the junior staff of my vessel in the art of manoeuvring.”

Capt. Christer Menfors, Stena Vision

The proof of concept has been created

in collaboration with Stena Line Scandinavia and

Chalmers University of Technology.

The scope of these exercises included, among others:• Applied hydrodynamics (IMO

manoeuvre tests, shallow water effects, ship interactions, etc.);

• Manoeuvring characteristics of different ships, including the controllable, semi- controllable and uncontrollable forces involved in ship handling;

• Planning, executing and monitoring passages in confined waters such as archipelagos (blind pilotage techniques on radar, controlled turns, etc.);

• Manoeuvring large ships with and without the use of tugboats.

After the course, all students were asked to answer a voluntary online questionnaire about their experiences with the tool.

Stena Line ScandinaviaStena Line Scandinavia has been using SEAMAN Online onboard on one of their v essels, the Stena Vision, since mid-2018. The ferry is operated between Karlskrona in Sweden and Gdynia in Poland.

Through SEAMAN Online, the crew of the vessel has had access to bespoke models of the two ports and of the Stena Vision ferry. The main use has been to test and evaluate different manoeuvres, especially in abnormal operational conditions such as harsh weather conditions or

limited propulsion power availability. It has also given junior staff the possibility to train port manoeuvring under the supervision of the more senior staff.

Commercial introductionBased on the experiences gathered from the Stena Vision and Chalmers University of Technology, the tool was updated during the summer of 2019 and commercially introduced to the market at the Donsö Shipping Meet in September 2019.

Both Stena Line Scandinavia and Chalmers University of Technology have decided to expand the use of SEAMAN Online in their organisations. At present, all vessels in operation by Stena Line Scandinavia have the possibility to use the tool as support for their operations.

At Chalmers University of Technology, all students of the Master Mariner programme will have their own personal login to SEAMAN Online. It will be used as a training and assessment tool on many courses during the entire four-year programme. Further reading and references are available at www.sspa.se/seaman-online-taking-availabili-ty-and-flexibility-to-the-next-level

12 Highlights 67 / 2020 – Oil spill risks in Arctic waters

Research project GRACE The EU Horizon 2020 project called “GRACE – Integrated oil spill response actions and environ-mental effects” was finalised in August 2019. The project focused on developing, comparing and evaluating the effectiveness and environ-mental effects of different oil spill response methods in a cold climate.

The results of the project are available for international organisations that plan and carry out cross-border oil spill response cooperation in the Arctic sea areas, but also for national organisations and authorities responsible for the response to, and mitigation of, oil spills. The risk assessment model for oil spills in the Arctic and sub-Arctic conditions was developed to be used in combination with the analytical tool for environmental assessment: Environment & Oil Spill Response (EOS), which also has been developed as a part of GRACE.

MethodologyThe developed spill risk assessment methodo-logy is based on well-established principles and methods, essentially Formal Safety Assess-ment (FSA) methodology which is the IMO´s proactive process to be used as a tool in the rulemaking process. Efficient big data proces-

Oil spill risks in Arctic watersAs the interest in the Arctic, its natural resources and its new potential fairways increases as the ice coverage d ecreases, the risk of severe oil spills in a sensitive and unique environment rises. The sensitivity of Arctic areas, in combination with its remoteness and the particularly harsh conditions in cold climates, increases the importance of adequate methodology for estimation of the risk. An oil spill risk assessment forms an important link in the chain of prevention, detection, control and mitigation of spills. SSPA has developed a method to provide answers to the questions; where, how often, what type of oil and the size of the oil spills that may be expected.

The oil spill risk assessment methodology

developed by SSPA contributes to the design of an appropriate

response by taking both the probability and consequences

of an oil spill into account.

sing of AIS data and integration of data from ship databases, combined with statistics on ship accidents, enable credible predictions of accident probability, associated spill risk and its severity in terms of spill volume. Low traffic intensity, sparse empirical accident data and highly varying ice conditions, however, make Arctic predictions particularly challenging.

The developed methodology is applicable on a local scale, as well as on a more regional scale, to identify the worst credible scenarios and the most probable scenarios for certain areas. Adequate capacity needs and response resources can thereby be estimated. The presented spill risk assessment method was applied at a trial site, Disko Bay in West Greenland.

Seasonal variationsThe presence of ice and severe Arctic conditions during a large part of the year prevent all ship traffic north of Disko Bay from January to April. A monthly accident index (AI) is calculated to show variations in accident frequency. The acci-

dent index calculated for the Arctic region correl- ates with traffic intensity in Disko Bay, yielding the highest values in August and September.

Representative fleetsBased on AIS data, the most frequent and the largest dimensioning vessels of different ship types are identified and selected to constitute a re-presentative fleet for the area. The selected vessels are used in the risk evaluation to identify the worst credible spill scenario. As the selected vessels are assumed to represent the total fleet in the area, a percentage distribution of the total fleet to each vessel is estimated based on traffic statistics. In the Disko Bay area, trawlers and fishing vessels are most frequent. Specialised icebreaking vessels to supply Greenland with necessities constitute the dominant traffic sailing in ice. The largest vessels, bulk carriers with a bunker capacity of about 3,000 m3, only operate in the area during the summer months when the Arctic characteris-tics are less significant. Crude oil tankers with large quantities of oil as cargo are not present-

Iceberg and tourist vessel in Disko Bay, Greenland.

Pho

to: S

hutte

rsto

ck

Risk matrix for oil spill in Disko Bay.

10-2

10-3

10-4

10-5

10-6

10 100 1,000 10,000 100,000

Pro

babi

lity

(spi

lls/y

ear)

Spill volume (m3)

General cargo

General cargo – collision

Oil/Chemical tanker

Oil/Chemical tanker – collision

Bulk carrier

Bulk carrier – collision

Container

Container – collision

Trawler

Trawler – collision

Chemical/product tanker

Chemical/product tanker – collision

Selected vessels for representative fleet in Disko Bay (DF: Destillate Fuel, RF: Residual Fuel).

Name TypeLengthoverall (m)

Fuel capacity(m3)

Cargo capacity– Liquid (m3) Comment

NS Yakutia Bulk carrier 225 DF: 260 RF: 2,310

– Largest vessel, only during summer time

Ugale Chemical/Product tanker

195 DF: 194 RF: 1,590

56,190 Largest tanker

Orasila Oil/Chemical tanker 89 DF: 306 1,862 Most frequent tanker, 5th most frequent in ice

Acadienne Gale II Trawler 71 DF: 648 – Most frequent vessel

Ivalo Arctica General cargo 45 DF: 130 – Most frequent vessel in ice, Icebreaking

Irena Arctica Container 109 DF: 84 RF: 804

– Most frequent container vessel

Nelly ForsmanProject Manager, Nautical & maritime risk-, safety, & environment analyses.

Nelly gained an MSc in Mechanical Engineering with a specialisa-tion in Sustainable energy systems from Chalmers University of Technology in 2012. Since joining SSPA in 2014, Nelly has been active in the field of maritime safety assessment and risk analysis. Nelly also has experience and knowledge of alternative maritime fuels and the environmental impact from shipping, including oil spill risk assessment.

Contact information E-mail: nelly.forsman@sspa.se

Björn ForsmanSenior Specialist, Nautical & maritime risk-, safety, & environment analyses.

MSc Mech. Eng. Björn joined SSPA in 1980 and has been active in areas related to the marine environme-nt, oil spill prevention and clean-up as well as the reduction of ship emissions and alternative fuels. Currently, maritime safety and risk analysis are the main fields of expertise in his projects and in the research projects that he is engaged in. He has also been the programme manager for a number of advanced international training programmes.

Contact information E-mail: bjorn.forsman@sspa.se

All illustrations by SSPA. .

Number of accidents per month and per casualty type reported in the Arctic between 1996 and 2017. Only a few accidents are registered in the Disko Bay area, which is why no monthly statistics could be derived.

0

5

10

15

20

25

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Acc

iden

ts/m

onth

Hull/Mchy. Damage Wrecked/Stranded Collision

Contact Fire/Explosion Foundered

ly operating in the area, which eliminates the probability of the largest types of spill.

Risk evaluationThe consequence component of the spill risk is quantified by a calculated spill volume in m3 for each specific identified accidental event and each identified dimensioning ship category. Associated probability and consequence figures are presented and compared in risk matrices to f acilitate identification and prioritisation of critical spill risk events.

For the Disko Bay case, accidents (grounding, foundering or ice damage) with a product/che-mical tanker are clearly indicated as a high-risk event in terms of spill risk.

Future outlookThe expected increase in future sea traffic in remote and sensitive Arctic waters calls for

enhanced preparedness and tools for prioritisa-tion of response methods, identification of risk hot spots, response capacity needs, and adequate localisation for resources. Emerging spill risks follow with the expansion of Arctic shipping and the risk profile will change dramatically with the stepwise transition from the use of HFO to distillate and hybrid fuels with lower sulphur content. New fuels and future fuel types also require revisiting the existing response technique, its efficiency and potential need for adaptation.

The combined output from technical and environmental prediction methods developed within GRACE and its different work p ackages will facilitate future planning processes for the sustainable utilisation and protection of Arctic resources, specifically by providing effective tools for the planning of oil spill response preparedness and for the design and selection of adequate resources.

14 Highlights 67 / 2020 – A renaissance of wind-powered ships

What is the right solution?Today, an increasing number of shipowners are contacting SSPA to find out whether wind propulsion could be a solution for them. In shipping there are no general answers – each case is unique. A shipowners’ way towards wind propulsion often starts with a broad review of available technologies. The first thing to decide is whether the target is wind assistance or wind propulsion?

Wind assistance technology is typically a device that provides a forward thrust resulting in about 5–10 percent fuel reduction. Apart from the wind technology device, the ship is a conventional ship. Recently, several wind assistance technologies have been installed on commercial vessels, for example Flettner rotors on Viking Grace and Maersk Pelican.

Wind propulsion technology denotes a ship concept almost completely propelled by wind. Typical solutions are large rigid wings, Dynarig, or other soft sail rigs. Today very few large

A renaissance of wind-powered shipsWith IMO’s newly adopted strategy for cutting greenhouse gas emissions by at least 50 percent over the next thirty years, the international shipping industry is in for some radical changes. Gradual improvements to today’s vessel concepts will simply not be sufficient. Recently, wind power has resurfaced as an option worth taking seriously and suppliers of innovative wind technology are appearing on the market. But which ones of the numerous solutions are most suitable? To what extent will they really reduce carbon emissions? SSPA has developed efficient prediction tools for both wind-driven and wind-assisted ships in order to support the development of more sustainable maritime transports.

vessels are built for wind propulsion, apart from a few super yachts. However, several projects are in the concept stage, for example the ongoing Swedish research project Wind-Powered Car Carrier (wPCC) with the project partners SSPA, Wallenius Marine and the Royal Institute of Technology (KTH). A wind propulsion technology requires that the ship is really designed for sailing, as opposed to a wind assis-tance solution that can be retrofitted to conven-tional ships (and removed again).

The number of available solutions may seem large, but practical considerations often limit the options. The ship may have to pass under certain bridges, restricting the rig height. A container ship has limited space on deck for wind propulsion devices. Dry bulk carriers need to allow space for cargo loaders or cranes to access the cargo holds. Most shipowners do not favour a solution that requires a larger crew and absolutely not a solution that puts the crew at risk when handling the device. Bridge visibility may also be a limiting factor on

smaller vessels. A customised technology review makes a solid basis for the decision process.

Ranking the optionsThe main question when ranking technologiesis often the amount of reduction in CO2 emissions provided by the wind technologies under consideration. The efficiency can, however, differ considerably from case to case depending on the ship size, route, speed and other substantial issues, and therefore published numbers from other vessels with the same technology can be misleading. Ranking of wind propulsion tech-nology options at this preliminary stage should be based on a numerical model of the ship in question and reliable data on the aerodynamic performance of the wind devices.

It is also important to consider the weather on the intended route. Some types of sail work excellently in a limited range of wind angles: kites, for instance, operate best in a following wind. The performance in all wind directions needs to be considered.

Wings, rotors or kites? Selecting and ranking the concepts at the early stage needs the combined knowledge of wind propulsion devices interacting with the ship hydrodyna-mics and taking risk and logistics into account. The process goes from a broad technology review to detailed assessment of fluid dynamics, risk, cost and logistics.

Sofia WernerSenior Researcher and Manager Strategic Research – Hydrodynamics.

Sofia received an MSc in Naval Architecture from

the Technical University of Denmark (DTU) in 2001 and a PhD in Naval Architecture from Chalmers University of Technology in 2006. She joined SSPA in 2007 and worked on ship design, CFD and towing tank testing for commercial clients for eight years. Since 2016, Sofia has managed the strategic research plans in the area of hydrodynamics. She is currently chair of the ITTC Specialist Committee on Combined CFD/EFD Methods.

Contact information E-mail: sofia.werner@sspa.se

Da-Qing LiSenior Researcher and Project Manager.

Da-Qing received his MSc in Naval Architecture from Huazhong University of

Science and Technology in 1986 and a PhD from Chalmers University of Technology in 1994. He joined SSPA in 1997 and has been working with various projects associated with propeller/waterjet propulsion, cavitation/erosion and shallow water problems using CFD tools and model testing. He was a member of the 26th and 27th ITTC Specialist Committee on CFD in Marine Hydrodynamics and an active participant and contributor to a number of EU projects.

Contact information E-mail: da-qing.li@sspa.se

Vendela SanténSenior Researcher and Project Manager.

Vendela has an MSc in Industrial Ecology and a PhD in Technology

Management and Economics. She has a background in research, primarily focusing on sustainable logistics and how companies can take action to reduce their transport emissions. Since joining SSPA in 2016, she has been involved in projects related to a modal shift to sea transport solutions as well as traffic analysis using AIS data.

Contact information E-mail: vendela.santen@sspa.se

Wind-Powered Car Carrier (wPCC)Towards a wind-powered car carrier vessel, from concept to a technical and financially feasible design.This project will develop a design ready to be built within 3–5 years. SSPA’s experts will contribute with extensi-ve research, for example regarding unconventional experimental methods, aerodynamic and hydrodynamic simu-lation methods, risk simulation and risk mitigation and new logistics solutions.• Project period: 2019–2022 • Partners: 3 • Financed by: the Swedish Transport Administration

Wind-Assisted Ship Propulsion (WASP)An EU–Interreg joint development project for commercially attractive wind solutions.This project will help accelerate the decarbonisation transition by giving the market and policy makers clear indicators on operational parameters, fuel savings, business models and a collection of additional demonstrator vessels to high - light the wind-assisting propulsion potential. • Project period: 2019–2021• Partners: 15• Financed by: the Interreg North Sea Europe programme, as part of the European Regional Development Fund (ERDF).

SSPA is a full member of the International Windship Association (IWSA) www.wind-ship.org

Ongoing research projectsSSPA’s route simulation software, SEAMAN,

together with our ship hydrodynamics database, is an efficient tool to predict the CO2 reduction. The largest uncertainty is the data of the wind propulsion device. Published numbers must be combined with engineering judgements and our experience of similar devices. The power consumption from operating the device is, of course, also considered as well as the installation costs.

Concept design and 3rd party assessmentWhen a supplier is selected, the concept can be evaluated in detail. Computational Fluid Dynamics (CFD) is an invaluable tool at this stage. The studies are often done in cooperation with the supplier to improve and customise the design for the given vessel.

The example illustrated shows a detailed flow analysis of a generic Flettner rotor. The flow is complex, with unsteady vortices which may cause vibrations. It should be noted that the flow is highly affected by the presence of the vessel freeboard and superstructure and by the atmospheric boundary layer. If there is more than one device, there may be strong inter- actions between them. These effects have a large impact on the total performance and must not be neglected.

It may seem obvious to focus the work on the airflow around the wind propulsion devices, but the hydrodynamics should not be forgotten. The lateral force from the wind propulsion device makes the ship slide sideways, which affects the resistance, creates an asymmetric flow into the propeller and requires additional rudder actions. If the thrust force from the

Influence of ship hull on flow around a rotor sail. The flow is highly affected by the presence of the vessel freeboard, super-structure and by the atmospheric boundary layer. If there is more than one rotor, there may be strong interac-tions between them. These effects have a large impact on the total performance and must not be neglected. The figure shows a generic design.

16 Highlights 67 / 2020 – A renaissance of wind-powered ships

SSPA Highlights is published by:SSPA SWEDEN AB

P.O. Box 24001, SE- 400 22 Göteborg, Sweden.Phone: +46 31 772 90 00 Fax: +46 31 772 91 24

E-mail: postmaster@sspa.se Web: www.sspa.seMH108772-01-00-A

SSPA is a world-leading maritime company that offers the latest knowledge within maritime solutions. 80 years of experience has placed us at the forefront of maritime development, applied research and qualified consulting services. The vision is to be recognised as the most rewarding partner for innovative and sustainable maritime development.

We have 100 employees with a head office in Gothenburg and a branch office in Stockholm. The company is owned by Chalmers University of Technology Foundation. The basis of our work is in the

areas of hydrodynamics, systems engineering, shipbuilding, logistics, environment, risk and safety as well as simulation modelling. We use our resources such as databases, analysis and calculation capabilities, laboratories, collaborative platforms and skills to create value.

Our clients and partners are shipowners, shipbuilders, ports, manufacturers and maritime authorities all over the world. We work towards customers who take a long-term holistic approach to their maritime systems. Together, we develop a safer, more energy- efficient and environmentally sustainable maritime sector.

You can download SSPA Highlights at www.sspa.se

All illustrations by SSPA. References are available at www.sspa.se/renaissance-of-wind-powered-ships

wind propulsion device is large, the propeller as well as the main engine may operate at a non- optimal load point. These effects are all combined into a prediction of the CO2 savings for the given vessel and route.

How to ensure an accurate safety level?Current ship design regulations and classification rules are generally only address conventional ship types, and a dedicated risk assessment study is required to iden-tify regulative gaps and to find solutions demonstrating equivalent safety levels.

Safe ship operation in adverse weather conditions imposes tough requirements on rig foundation and intact stability, and extreme wind loads of 50 m/s or more should be considered.

The forces from wind propulsion devices may impair the manoeuvring performance,

especially in waves. Smart integration of the rig control system, rudder control and propellers may, however, offer additional manoeuvring and deceleration capabilities. The installation of a wind propulsion system may permit the use of a less powerful mechanical propulsion engine, although the minimum engine power must also be addressed from a risk perspective.

Wind propulsion devices will add to the windage of the vessel and correspondingly also increase the mooring loads, possibly calling for enhancement of fender and bollard equipment on the quayside.

Risks related to technical or operational failures of wind propulsors or control system components should also be addressed by the risk assessment study, e.g. by the use of Failure Modes and Effects Analysis (FMEA). Model testing may be necessary to confirm compliance with manoeuvring criteria and possible c ounteractions.

How does a wind-powered ship influence the logistics performance? The logistics performance of a wind-powered ship is crucial for shipowners to consider in order to attract new and keep current customers. Applying wind propulsion technologies may influence the logistics performance, especially if the aim is a high degree of wind propulsion. Major logistics aspects to consider are the cost of the operations, emissions, service level (such as transport time, frequency, reliability), route and risk of damage of goods.

A ship with a high degree of wind propulsion will most likely have a slower speed than a conven-tional ship, and, for it to be successful in its imple-mentation, the customers’ sensitivity to transport time needs to be assessed. Large emission savings might be an order winner for new customers.

Regime 2 is in a quasi-steady state, in which the bound vortex is not shedding and a pair of tip vortices are created at the end disc. A trail-ing vortex is also formed near the root. These vortices are strong and persistent.

In Regime 3, the tip vortices generated at the end disc are fluctuating. There is one or more trailing vortices started at the root and wandering along the rotor between the root and the tip.

In Regime 1, where the SR is low, a pair of bound vortices is shedding alternately from the pressure and the suction side of the rotor. The tip vortices are weak and stable.

The dynamic behaviour of the vortical flow behind a Flettner rotor can be categorised in three regimes depending on the spin ratio SR (i.e. the ratio of the peripheral velocity of the rotor to the freestream velocity).

Shed vortices

Regime 1 Regime 2 Regime 3

Tip vortices Tip vortices

Trailing vortices

Trailing vorticesBound vortices