Simulations and the importance of high-quality dataSEAMAN Simulation toolbox.

Highlights.Issue 66/2019

Page 2 – 3

Page 14 – 16

Skin Friction databaseAn interactive tool that can be used without requiring background knowledge in hydro dynamics.

Defining normal ship behaviour and safety distance to other ships in open watersA case study to further investigate the domain and the use of new methods and knowledge.

PAGE6 – 7

Original Tracks Optimised Tracks

B

A

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Route optimisation based on AIS tracksInternal SSPA software used to optimise routes in the Baltic Sea for fuel efficiency.

Page 8 – 9

A maritime (container) supply chain

European port Port of Gothenburg

Effects?

Logistical consequen-ces of the Gothenburg container port conflictWhat happens when supply chain disruptions occur?

Page 12 – 13

Thorough model testing required to make cruising in tough environments sustainableHydrodynamic testing partner.

Implementing S1000DContinuously managing tech­nical publications for a large fleet of military assault and support crafts.

Page 10 – 11

2 Highlights 66 / 2019 – Skin Friction database for the maritime sector

I believe it has been a long time since we last faced so many big, global challenges. We are facing a changing climate. We are facing political situations creating uncertainty in many countries. We are facing the potential for an escalating trade war between the economic superpowers in the world.

Most of these challenges affect the maritime sector, and some of them possibly present a bigger challenge for maritime business than other sectors.

Personally, I believe that the hardest will be how the shipping community solves the environ­mental requirement set by the Inter national Maritime Organization (IMO) to reduce green­house gas (GHG) emissions for all international shipping by at least 50% before 2050.

There is still an open question surrounding how we can solve this, and I don’t think anyone currently has the answer. However, I am convinced that the answer will not be one big-fix solution for the problem, but rather several small, efficient solutions that combine to achieve the required levels for reduced emissions.

SSPA wants to be a part of the solution, and we will be dedicated to optimising maritime systems for a reduction in GHG emissions now and in the future. We believe strongly that a very good first step towards meeting the objectives is to reduce fuel consumption.

This edition of Highlights contains articles that address research results on how to reduce the environmental footprint from shipping. The result may not be ground­breaking, but it shows that there are several actions that we can take.

Another area that the IMO and other interna­tional maritime organisations are focusing on is how to improve safety within maritime operations. This is also an area where many small steps will add up to a big change.

SSPA is devoted to being part of the develop­ment to ensure and improve safety at sea, which is why you will find several articles describing, in a broad sense, how we can assist the maritime sector in improving their opera­tions safely.

I hope you will find some articles to catch your interest. Pleasant reading!

Stefan EliassonPresident & CEO

Highlights.

Skin friction is responsible for 50 – 85% of the total resistance the ship must overcome to keep its speed. It is therefore important from an economical and environmental point of view to ensure that the cost of increased fuel consumption due to roughness does not surpass the cost of surface maintenance. It is not a trivial task for ship owners and shipyards to decide which coating to use or how often the surfaces should be recoated or cleaned based on cost/benefit analyses. SSPA has completed a research project with the aim to gain increased knowledge of the effect a rough surface has on skin friction. This project has also resulted in an interactive tool that can be used to estimate fuel consumption without requiring background knowledge in hydrodynamics. This tool is the “Skin Friction database”, which will hopefully contribute to better surface treatment of vessels, that in the end can reduce costs and emission of greenhouse gases from the maritime sector.

Skin Friction database for the maritime sector

There are several published measurements that link surface roughness to skin friction but none which cover all (or most) of the possible surface topologies seen on vessels. Estimating the increase in delivered power due to deterio­rating surface conditions requires insight in relevant literature and the means to convert that knowledge to the influence on skin friction. The goal of the Skin Friction database is to increase

the knowledge of rough surface effect on skin friction and create an interactive tool, which can be used to better estimate fuel consumption due to hull roughness.

The database consists of three elements: Model tests of rough surfaces, extrapolation to full scale vessel length and speed and the database interface including a fuel consump­ tion tool.

Skin Friction database

Available at https://www.sspa.se/tools-and-methods/skin-friction-database along with instructions, and a more extensive description than available in this article.

The database consists of three elements: Model tests of rough surfaces, extra-polation to full scale vessel length and speed, and the database interface including fuel consumption tool.

Acknowledgement is due to Jotun and the Löven Center as partners, and the Swedish Energy Agency, Region Västra Götaland and MARIA for funding the project. The project will be continued with more emphasis on hull cleaning and Computational Fluid Dynamics (CFD) simulation of rough surfaces in the project “RÅHET” (Roughness) funded by the Swedish Transport Administration.

Skin Friction database interface.

The Skin Friction database is an interactive tool, which

can be used for better estimates of fuel consumption due to

roughness without the necessity for background knowledge

in hydrodynamics.

Model testsA flat plate was used to test various rough surfaces in SSPA’s Towing Tank. By applying coatings, growing bio fouling in the ocean and creating simulated surfaces of flaking paint and cleaned surfaces (a total of 16 rough surfaces) and towing the plate through the Towing Tank, measuring the resistance, the skin friction for each surface can be extracted. All rough surfaces tested were chosen to reflect surfaces normally seen on commercial vessels.

Michael Leer- AndersenProject Manager.

He received his MSc in Naval Architecture from Technical University of

Denmark (DTU) in 1996. He started at SSPA in 1997 at the R&D department and has mainly worked in the area of CFD, wash- wave prediction, friction on rough surfaces, and has recently become responsible for ocean energy conversion at SSPA.

Contact information E-mail: michael.leer-andersen@sspa.se

Sofia WernerManager Strategic Research – Hydrodynamics

Received an MSc in Naval Architecture from 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 with 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

Skin Friction databaseThe database interface is interactive and consists of the following sections; vessel information, which requires only a minimum amount of information to allow for easy use, and graphs of skin friction in model and full scale. As the number of measured surfaces are quite large and will be increased over time, a filter for displaying surfaces along with additional information about the surfaces (such as roughness height, type and pictures) are available.

Finally, based on the delivered power of the vessel, the fuel consumption increase for each selected surface is presented in absolute numbers and in graphical form.

The measurements completed for the database can be seen as a significant contribution to the volume of skin friction measurements on rough surfaces for the maritime industry. However, the main goal of the database, and the reason to include the interactive interface, is to offer vessel management an easy to use tool to evaluate the impact of rough surfaces on fuel consumption, thus allowing a better cost/benefit analysis of when and how to improve a vessel’s surface condition.

Ultimately, it is the hope that the database can contribute to decisions leading to generally better surface treatment of vessels, reducing costs and emissions of greenhouse gases from the maritime sector. The extrapolation and fuel estimation tool are a rather coarse method, but then again so too is determining a vessel’s rough surface distri­bution. More refined estimates can be obtained using Computational Fluid Dynamics (CFD) simulations.

Along with measurements from other laborato­ries, these results are used and presented in the database interface as input to the extrapolation and the fuel consumption increase estimate also included in the database interface. The extra­polation method consists of Granville similarity for extrapolation in the length dimension and roughness function extrapolation in the speed dimension according to the Towing Tank Confe­rence (ITTC) procedure. All photos and illustrations by SSPA.

7-metre flat plate in SSPA’s Towing Tank.Antifouling coating applied with same procedure as on a full-scale vessel.

Definitely not a good solution.

4 Highlights 66 / 2019 – Route optimisation based on AIS tracks in the Baltic Sea

Original tracks (red) and optimised tracks (green). Emphasis is placed on areas A, B and C.

Route optimisation based on AIS tracks in the Baltic Sea

Original Tracks Optimised Tracks

© SSPA Sweden AB© OpenStreetMap contributors

B

C

A

The route optimisation analysis was part of the FAMOS Odin project, to which SSPA also contributed with an analysis of common Under Keel Clearance (UKC) in the Baltic Sea. Other tasks in the project, performed by fellow project partners, included bathymetric (water depth) measurements of large areas.

AIS dataAccess to a real­time feed of Automatic Identi­fication System (AIS) data was provided for the project by the Swedish Maritime Administration. The data used in this analysis correspond to the whole of 2017. The dataset consisted of app­roximately 1.6 billion AIS messages, which were reduced to roughly 50% when filtered for commercial traffic only (AIS ship type categories 60 – 89).

The AIS data subset used in the analysis con­tained all tracks from tanker ships that travelled the area during 2017 (shown in the figure), although some tracks were excluded from the optimisation. This was either due to odd ship dimensions (too big or too small), which may have been wrongfully entered by the mariner onboard the ship, or the track crossing areas that were too shallow according to the bathymetric data, etc.

In the relatively shallow waters of the Baltic Sea, ships will have a higher fuel consumption compared to when sailing in, for example, the open waters of the Atlantic. This is due to higher resistance when the water depth under the keel is lower. In this article, we present the results of taking stored AIS tracks and optimising their route geometry as well as their speed to minimise fuel consumption, i.e. to minimise the shallow water resistance experienced by each ship. The results show key changes in traffic patterns, specifically fairway shortcuts that could be taken if there are no safety concerns.

given a desired Estimated Time of Arrival (ETA). The analysis considers shallow water effects, based on ship dimensions and draught, as well as speed over ground. This study did not include Traffic Separation Schemes (TSS) nor effects from currents and wind, since the scope was to investigate routes in general.

Route optimisationInternal SSPA software for route optimisation based on energy efficiency was used in this analysis. The software tool has been developed and used in both commercial and research projects. The software traverses a bathymetry raster and finds the most energy efficient route

SSPA AIS database

SSPA has stored years of AIS data, from both Swedish coastal waters gathered by the Swedish Maritime Administration (SMA) and across Europe via the crowdsourcing initiative AIS Hub. At SSPA, we have the ability to work with all AIS data formats for customer-specific analyses.

that travel on a shorter optimised route will reduce their speed, leading to double the fuel savings – resulting from both the shorter route length and the lower speed. If the optimiser is instead set to the same speed as in the original track – which can be understood to be a ship using a fixed service speed – then the results will be somewhat different: the optimiser will put more emphasis on finding deeper routes and less focus on the length of the route.

On a higher level, the difference in optimisa­tion criteria relates to the contract specified for transporting the cargo. Ships either need to be at the destination at a pre­agreed time or will travel there at a fixed service speed. Optimising with a fixed ETA does the former and, with a fixed speed, the latter.

The fact that the constraints of the optimisation – in this case with the fixed ETA – play such a significant role in the results also highlights the importance of understanding the implications that these constraints put on the result, since otherwise the optimised route could actually be a worse alternative than the original route. When weather and currents are included, as in the case of optimising planned routes in opera­tional shipping, then understanding the implica­tions of the optimisation constraints becomes even more important.

The figure in this article should be considered an example of what can be achieved with route optimisation. Ship operators can save fuel, but extra care must be taken to make sure that optimising is done under the right constraints and with accurate models and data. SSPA plans to continue to develop its existing route optimi sation models and tools as part of future colla borative projects.

Nicole CostaProject 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 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 contri- buted to European and regional maritime digitalisation projects.

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

Henrik HolmConsultant.

Henrik specialised in Complex Adaptive Systems at graduate level at the department of

Engineering Physics at Chalmers University of Technology. He was previously a Product Manager at Playscan AB and a Software Architect at Avail Intelligence, both in Gothenburg, Sweden. Henrik worked at SSPA between January 2013 and May 2017, and now continues to collaborate with SSPA as a consultant, participating in various research projects developing route optimi-sation and mathematical modelling.

Contact information E-mail: henrik@berakningsbyran.se

AnalysisThe optimiser was set to require a UKC of at least 20%, i.e. a minimum UKC of 2 metres for a draft of 10 metres. Out of 19,159 AIS tanker tracks, 8,273 (approximately 43%) benefited from optimisation in fuel efficiency. Approxi-mate fuel savings per track amounted to an average of 11% compared to the original track.

Although there was a theoretical 11% gain from optimising the routes, it is not possible for individual ships or operators to achieve such a gain. This is because there are several TSS areas in the Baltic Sea that ships must follow, and TSSs were not considered in the optimi­sation. However, from a regulatory perspective, shipping as a whole could benefit from moving – or adding alternatives to – the TSSs. As seen in the figure, from an energy efficiency point of view, the TSS east of Stockholm (area A) forces northbound traffic to sail further out east than necessary. From a safety point of view, however, there might be a higher risk in those waters, since there are numerous small islands and rocks in the vicinity.

The traffic south of Bornholm (area B), as seen in the figure, would benefit from taking a more northerly route according to the optimisa tion analysis, but still south of Bornholm if the route continues south of Denmark (Kadettrännan). If, however, the route continues into Öresund, the route should remain north of Bornholm.

For south of the area between Gotland and Hoburg (area C), as can be seen in the figure, the greatest gain from performing optimisation was from not taking the route south of Hoburg when the route continues to the Gulf of Finland.

As stated earlier, if the optimiser is set to the same ETA, ships will arrive at the end of the optimised track at the same time as in the original track. These optimisation criteria have a signifi­cant effect on the results, considering that ships

FAMOS is an international project that comprises fifteen organisations from seven countries around the Baltic Sea. The project aims to map the water depth of previously unsurveyed areas used for commercial shipping in the Baltic Sea and to implement the BSHC HELCOM Re-survey Scheme. FAMOS also aims to help reduce emissions and the cost of fuel in the Baltic Sea by providing exact hydrographic data which can be used to re-evaluate the preferred routes used by vessels today, and to contribute to improved UKC awareness navigation by providing better data regarding water depth, the vessel’s vertical position and pre-calculated level of water surface at sea. www.famosproject.eu

Illustration by SSPA.

6 Highlights 66 / 2019 – Defining normal ship behaviour and safety distance to other ships in open waters

All vessels are expected to comply with interna­tional regulations and practices as they navigate in open waters and in waterways. As ships approach each other, the distance between them must be “well clear”. This “well clear” area surrounding the ship is often referred to as the ship domain and has no fixed or defined mini-mum distance according to the regulation. Normal behaviour is considered to be safe beha­

Defining normal ship behaviour and safety distance to other ships in open watersWhen ships approach each other, there are recommendations on the minimum distance to keep. The geometrical shape that this distance forms around the vessel is defined as the ship domain and it has been studied since the early 1970s. The progress in computer capacity and the introduction of Automatic Identification Systems (AIS) challenge SSPA to further investigate the domain and use new methods and knowledge. When performing maritime spatial planning, e.g., when implementing traffic separation schemes or when building maritime infrastructure, it is very important to understand normal ship behaviour. A poor understanding of how a ship normally behaves may lead to unreliable estimations of risks at sea. To assess how ship domains vary under different geographical settings and in different types of meetings, SSPA performed a case study. Our researchers studied over 600,000 ship encounters at 36 locations around the Swedish coast. The conclusion is that the ship domain has the shape of an ellipse with half axes radii of 0.9 and 0.45 nautical miles in open waters. In contrast to previous research, it has also been discovered that the ship domain is unrelated to the length of the ship.

viour at sea, i.e. vessels that deviate from normal behaviour may be regarded as uncomfortable to the other vessels and thereby result in an increased risk of collision.

For example, the width of a Traffic Separation Scheme (TSS) is related to the traffic flow and the ship domain, therefore, a large ship domain requires a large TSS and a small ship domain may interfere with the safety when the traffic

becomes too dense. In the case of maritime infra­structure, an underestimate of the proba bility of collisions may lead to an increased risk of collisions and grounding accidents, whereas overestimating may lead to excessive costs when building maritime infrastructure.

Practical implications and defining normal ship behaviourTo assess how ship domains vary under different geographical settings and in different types of meetings, SSPA performed a case study, using a new method. The researchers used AIS data collected by the Swedish Maritime Admini­stration during the entire year of 2016. In total 36 different locations were studied, 24 in open waters and 12 in restricted waters. The data volumes for one year are enormous and in order to handle it, all data was transferred from GPS positions into lines.

Two circles are drawn for each of the 36 loca­tions, all ships passing the inner circle are treated as Own Ships (OS) and all ships passing the outer circle at the same time as an OS is present are treated as Target Ships (TS). Then the lines for both OS and TS are split into points every second and the distance and bearing between them are measured. The long list of OS, TS, bearing and distance are now filtered and grouped on each 5° bearing and arranged by distance. Since the chosen definition of the ship domain in this research is where it is normal to pass each other, therefore everything greater than two sigma is considered normal. The ship domain is the border between normal and abnormal, which is marked as the red line in the figure on top of the next page.

Normal behaviour is considered to be safe behaviour at sea, i.e. vessels that deviate from normal behaviour may be regarded as uncomfortable for the other vessels and therefore result in an increased risk of collision.

All illustrations by SSPA.

Geographical characteristics influences the shape and sizeThe ship domain is relatively constant in open waters, but restricted waters influence the size and shape of the ship domain. The open water locations at the Kattegat and Bornholmsgatt locations, have a rather similar size and shape, and represent what is typical for open waters with predefined routes and/or TSS. In contrast, the Öresund – Drogdgen channel is a narrow passage, which illustrates that the two­sigma line forms an oblong shape. Furthermore, Öresund – East of Ven represents an example with dense crossing traffic, which renders a two-sigma line with a more circular and smaller shape. This is, of course, expected since ships keep a closer distance rather than risk running aground; it also proves that the static shape and size of the ship domain becomes dynamic in restricted waters.

In the figure below to the right is the ship domain sepa rated between overtaking and crossing situations. In overtaking situations the major axis of the elliptic ship domain is directed in the same direction for all vessels,

This represents seconds of meetings at one of the locations in the Bornholmsgatt southeast of Sweden. Red indicates many meetings and blue few, the red line (95%) is the ship domain.

Example of ship domains in different locations.Example of ship domains in different types of intersections.

The ship domain for different ship sizes compiled from all open water locations. The length of the ships (both OS and TS) is grouped into 40-metre intervals.

The average shape of the ship domain in open waters is an ellipse with radiis of 0.9 x 0.45 Nautical Miles.

hence in crossing situations the direction of the major axis is mixed, and the larger axis of the ellipse is turned. Therefore, the ship domain in over taking situations resembles an ellipse, whereas in crossing situations, the ship domain resembles a circle.

As mentioned previously, the ship domain was introduced in the early 1970s and was then defined as an ellipse with radiis of 4 x 1.6 ship lengths. Measuring the ship domain in

the “unit” ship lengths has since then been the standard.

Our experts’ new findings show that the ship domain has the shape of an ellipse with half axes radii of 0.9 and 0.45 nautical miles in open waters. In contrast to previous research, it has been discovered that the ship domain is unrelated to the length of the ship. This means that smaller ships pass each other at the same distance as larger ships, see the figure above.

The change of passing distance is probably due to better risk management on­board and the introduction of Automatic Identification Systems (AIS) which shows both small and large ships.

The findings are described in detail in an article written in The Journal of Navigation. The project will run until 2022, currently financed by Vinnova, Interreg ÖKS, Logistik och Transport stiftelsen and Norwegian Public Road Admini stration.

Axel HörtebornProject Manager, Risk Management

Axel graduated from the Faculty of Engineering, Lund University in 2013

with a MSc in Risk Management & Safety Engineering and joined SSPA after gradua-tion. Currently he is doing an industrial PhD at SSPA and Chalmers University of Tech - nology, specialising in risk management connected to maritime infrastructure.

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

8 Highlights 66 / 2019 – Logistical consequences of the Gothenburg container port conflict

Higher costsFor companies sending or receiving goods there were financial consequences. More expensive road transports followed from goods being rerouted through other ports. Delays led to lost sales, higher costs for storage space for containers and rent for containers. Furthermore, to ensure that goods arrived in time, more expensive transport solutions, such as air freight were used.

Delays were common. Either the containers were stuck in port or containers were rerouted through other ports, which took longer. Apart from affecting customer relationships when promised delivery dates could not be met, a serious consequence of these delays was missed campaigns or seasons in stores. While companies importing goods could experience production stoppages, companies exporting goods had containers that they could not ship, which took up space. They further reported that it had impli­cations for their customers’ productions.

The disruptions to the goods flow also meant a lot of extra work. This involved time spent trying to handle the disruptions for customer­facing staff, planners, loading staff, and warehouses. Staff had to keep up to date regarding delivery times and new transport solutions, but also more document handling. Several of the companies described a high workload for their staff. Some of their customers were angry because the goods in­turn were delayed to them, and it was not easy providing information regarding delivery when lacking that information themselves. Companies described overtime, changes to holiday plans, and extra staff to manage the most hectic period during the largest disruptions. In addition, more long­term and proactive work was put aside for later to deal with the crisis of supply disruptions.

Bad for the environmentFrom an environmental point of view, the supply disruption in the port of Gothenburg meant a

greater reliance on modes of transport that are worse for the environment. Several companies used air freight to a certain degree to solve critical transports. When containers were sent via other ports the distances were generally longer, for example, containers were collected from ports in mainland Europe, Denmark, Norway and southern Sweden. For the containers that were rerouted to other ports, the transport between company and port were to a larger degree per­formed by truck rather than by rail compared to normal circumstances.

Various actors affectedIn addition to the companies exporting and im­porting goods, many other actors were affected. The shipping companies were not able to unload and load as many containers per stop in the port of Gothenburg. This meant that some containers were left longer in European ports. Some decided to use smaller ships for calling

Logistical consequences of the Gothenburg container port conflictDuring the last few years, companies exporting and importing goods have experienced severe difficulties with goods going through the container terminal at the port of Gothenburg. A conflict between the terminal operator and the largest union has resulted in various strikes, blockades and a lockout throughout 2016 and 2017. As a consequence, goods have been delayed and rerouted. As part of a research project, SSPA researchers have mapped the logistical consequences for various actors in the supply chain as well as what they have done to mitigate these effects.

The knowledge from this research will benefit both authorities and industrial actors in planning for how to act when supply chain disruptions such as port conflicts occur.

A maritime (container) supply chain

European port Port of Gothenburg

Effects?

Illustration by SSPA.

in Gothenburg (e.g. feeder ships). The shipping companies decided to unload and load containers in other ports. For the shipping companies this meant route changes and higher costs for calling at more ports. More drastically, bookings to Gothenburg were refused. Agents for shipping companies report that Gothenburg is now seen as less competitive and thus less interesting for shipping companies compared to other ports.

With a rapid increase in the number of contai­ners to other Swedish ports capable of handling containers, the total capacity was strained and several ports set a number of restrictions regar­ding port calls. One reason for congestion in the ports was the shortage of trucks for transporting the containers.

The hauliers either spent a long time queuing in the port of Gothenburg or had to drive longer distances to collect or drop off containers in other ports. With each drive taking longer, they did not have time to transport as many containers. As a result, the demand for trucks was higher than what was available.

Freight forwarders, who arrange much of the transport for companies importing and exporting goods, spent more time per shipment, arranging new transport, for example, finding trucks to collect containers in other ports.

Rail connections were also affected. When companies did not want to send their goods via

Gothenburg, volumes decreased and rail connec­tions to other ports became more popular. Some containers still used rail via Gothenburg, and trucks between Gothenburg and the new port.

Companies loading and unloading containers in the Gothenburg area were also affected. With the goods rerouted to other ports, fewer companies were interested in sending their goods via Gothenburg for loading. Additionally, with containers in storage for a longer period of time, there was a shortage of empty containers for loading new goods, and containers had to be collected from elsewhere (often by road).

Different phasesThe actors have experienced three phases: urgent crisis, adaptation, and stabilisation. During the urgent crisis the companies reactively tried to solve the situations they faced, such as goods not arriving and goods showing up in different ports than anticipated. The urgent crisis meant high workloads for many of the actors and a lot of searching for information and alternatives.

During the second phase, adaptation, the actors put in place more long­term actions to minimise the effects and the likelihood of conse­quences. For example, companies decided on and put into place new transport solutions, such as using other ports, other routes, and ordering earlier. In this second phase there was a lot of

Sara RogersonProject Manager

Sara has a PhD in Technology Management and Economics. She has conducted research in

logistics since 2009, primarily on sustainable logistics, efficient transport, purchasing and urban logistics. At SSPA, Sara has been involved in projects related to modal shift to sea transport solutions, such as IWTS 2.0 and Sjö-tripp.

Contact information E-mail: sara.rogerson@sspa.se

Martin SvanbergProject Manager.

Martin has an MSc in Mechanical Engineering and a PhD in Technology Management and

Economics. He has conducted research in logistics since 2009, focusing primarily on energy supply chains. At SSPA, Martin has led and been involved in research projects on Urban Shipping, Short-sea Shipping and Modal Shift.

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

uncertainty regarding whether there would be more issues related to the port conflict. In this phase, it was more common to have a plan B. Companies moved from the crisis to the adaptation phase at a different pace, where some companies hoped that the port conflict and its effects would end while others implemented alternatives quickly.

In the stabilisation phase, business returned to a more steady­state. Some companies decided to return their goods flows to the port of Gothen-burg, while others have found new transport solutions that they think work better and have decided not to return to Gothenburg. The cost of maintaining alternatives is generally deemed too high. Nevertheless, experiences in the crisis and adaptation phases mean that relationships have been formed and processes established that would lead to a quicker reaction should a similar situation occur again.

The conflictThe port conflict in this article is between the terminal operator AMP Terminals and one of the unions, Svenska Hamnarbetarförbundets avdelning 4. It has been important in this research project not to address the labour market conflict itself but focus on the logistical consequences for other actors.

The research project

SSPA and the University of Gothenburg (School of Business, Economics and Law), are jointly investigating the consequences of the port conflict from a supply chain perspective for various types of actors in Sweden. This knowledge benefits autho-rities and industrial actors in planning for how to act when supply chain disruptions such as port conflicts occur.

SSPA focuses on analysing the changes in maritime container traffic and its environ-mental impacts. The maritime container traffic is analysed over time with AIS data

and a scenario-based environmental impact assessment is made. Our experts also study how the industrial actors have been affected and which measures they have taken and can take to mitigate the consequences. More than 30 interviews with various actors have been conducted, providing a thorough overview regarding consequences during 2016 – 2018.Swedish Transport Administration, Swedish Maritime Administration, Lighthouse and SFO Transport are financing the two-year-project, which started in 2017.

10 Highlights 66 / 2019 – Implementing S1000D for Swedish military assault and support crafts

The case for high-quality technical informationWhile the case for accurate, reusable, and acces­sible technical information may seem indisputable, surveys in many industries over the last few decades have clearly shown that vast amounts of technical support are spent unnecessarily, due to the lack of correct information about the pro­duct or system at hand. Some companies in the informa tion logistics field quote from customers that up to 30% of a service technician’s time is spent on searching for information across sources that are known to be unreliable.

For military systems that typically have a very long lifecycle, these problems may soon lead to unmanageable risks and costs. It is therefore not surprising that defence industries and defence procurement administrations very early saw the

need for a technical strategy and became strong stakeholders in S1000D.

Technical information in the analogue eraAs military systems became more complex during the latter half of the 20th century, the amount of technical information rose dramatically. In 1979, the U.S. Navy listed 25 million pages of tech­ni cal manuals, and added somewhere between 300,000 and 500,000 pages annually. In 1991, the Swedish Defence Materiel Administration distributed 4,500,000 pages of technical orders to 400 national subscribers.

In contrast to this, the entire technical informa­tion for a British Type 45 destroyer – information that is managed in S1000D – amounts to the equi­valence of 120,000 pages and is accessible using

a tablet viewer. S1000D is now the principal specification in global use for larger aerospace and military technical publication projects.

A brief history of S1000DS1000D can be traced back to 1984, when seven European countries started working on harmo­nising various national and international aero­ space specifications. At the time, there were no common technical information standards for collaborative projects and reuse and leverage of information was difficult or even impossible.

The first issue of the specification was released in 1989 and while the early issues had a strong focus on aerospace systems, the specification has since developed and is now designed to support any air­, land­, or sea­based vehicle or equipment, be it military or civilian.

Key concepts of S1000DThe S1000D specification lays out processes and methods for the production, maintenance, quality assurance, data transfer, and presentation of technical publications.

Enforcing XML (eXtensible Markup Language), the specification separates form (i.e., layout) from content and the technical information can easily be published in a variety of output formats, such as print, PDF, and HTML for desktop, tablets, and mobile devices.

One of the key concept in the specification is the data module, which is a small, reusable container of information, such as a task or a description. The specification describes how to break down technical information for a complex system into data modules from a functional and /or physical point of view.

Each data module is assigned a data module code, which, among other things, tells the user how the data module relates to the system in whole and what type of information it contains. In order to avoid naming collisions in interna­

Implementing S1000D for Swedish military assault and support craftsHow do you continuously manage technical publications for a large fleet of military assault and support crafts, differing not only by several series and versions within its two classes – Combat Boat 90 and Light Support Vessel – but also with regard to lifetime extensions, rapid reconfigurations for missions abroad, and changes driven by technical orders? You do this by implementing S1000D, the International Specification for Technical Publications. SSPA supports the Swedish Defence Materiel Administration (FMV) in several projects with information analysis, data conversion, restructuring, content revisions, and quality assurance.

Example of what an Interactive Electronic Technical Publication (IETP) may look like.

Mats BrobergS1000D Information Manager.

Mats has an MA degree from Uppsala university and joined

SSPA in May 2018. His previous job experience includes Technical Documen-tation Manager at FLIR Systems, and Service Information Manager at Getinge. At FLIR he worked with process develop- ment relating to technical information, such as automation of typesetting tool - chains, industrialisation of publishing strategies, and XML and standards-based workflows and technologies.

Contact information E-mail: mats.broberg@sspa.se

tional projects, each data module code starts with a globally unique model identification code.

Prior to publishing, data modules are arranged in a publication module, which becomes the principal technical publication. Since the tech­nical information is modular by design, it is reusable and the publication manager can easily remove or add data modules and/or create enti­rely new publication modules.

Central to the specification is also the far-driven semantic tagging, which both enables import of data from external sources – e.g., spare parts data from materiel management databases – and extraction or processing of specific data for down­stream of off­stream purposes.

The MIMI breakdown structureAs mentioned previously, S1000D provides the means to break down technical information for a product or system. This break­down structure

is called the Standard Numbering System (SNS) and the specification offers a number of main-tained SNSs, e.g., one for general sea vehicles.

However, in the Swedish Navy there is an existing break­down structure that is extensively used, not only for technical information but also for service & spare parts management, lifecycle management, repair analysis, and so on. This structure, which dates back to 1973 and replaced several older break­down structures at the time, is called MIMI – Marin Installations- och mate-rielindelning (“Marine Installation & Materiel Classification”). In our projects, it was critical that this break­down structure was retained, as so many existing workflows and activities in the navy relied on it.

The applicability conceptThe Combat Boat 90 fleet comprises around 140 individual vessels in five different series and 20 different versions and variants. For the Light Support Vessel, there are 16 individual vessels in three different versions. Fixed and non-fixed equipment in these boats differ not only by class, series, version, and variant, but may also be subject to a temporal aspect, such as the implementation of a technical order, whether or not a specific vessel has yet been subjected to dry­dock upgrades, and so on.

From a technical information standpoint, this is called applicability of information. For ex­ample, a data module describing the engine cooling system may include information on two different engines that are both in use across an

Combat Boat 90Length: 15.9 metresWidth: 3.8 metresDraught: 0.8 metresPropulsion (one of the following):• 2 × Scania DSI 14, 625–675 hp,

V8 diesel engines• 2 × Scania DI 13, 700 hp,

straight 6 diesel engines

Light Support VesselLength: 24.6 metresWidth: 5.4 metresDraught: 1.1 metresPropulsion: • 3 × Scania DSI 14, 675 hp, V8 diesel engines

entire vessel class. By setting different appli-cability on the two sections, either section can be generated in a publication, depending on which engine is installed.

Similarly, for a dry­dock upgrade, a data module may contain information on both an existing and a planned installation. By setting a switch in the publication system, the new and correct information can be turned on immedi­ately, once the dry-dock upgrade is finished.

Key benefits for the customerOnce finished, we hope that our projects with the Swedish Defence Materiel Administration will add considerable value in several different areas. Some of these include the following:• Adoption of an established specification

(S1000D) and data format (XML) for collabo-ration and long­term preservation of digital information.

• A modular information approach with a strong focus on re­use and leveraging of the existing MIMI break­down structure.

• Reduced life cycle cost by providing complete, accurate and easily accessible technical information.

• Powerful means to address future hardware changes on the vessels by rapidly recon ­figuring the technical information.

• Paving the way for various dynamic outputs, such as Interactive Electronic Technical Publications (IETPs) for tablet and mobile viewers, augmented reality (AR) deliverables, and more.

S1000D is now the principal specification in global use for larger aerospace and military technical publication

projects.

Photo: Swedish Armed Forces.

Photo: Anders Sjödén, Swedish Armed Forces.

12 Highlights 66 / 2019 – Thorough model testing required to make cruising in tough environments sustainable

Purpose-builtThe exploration cruise sector currently runs on an ageing fleet of converted vessels. Tradition-ally, these vessels have been existing passenger ships adapted to cope with tough polar environ­ments. However, the new generation of vessels is purpose-built, raising operators’ and final custo­mers’ expectations of the design’s performance.

The environmental impact, safety at sea and not least the user experiences are all very much the focus when designing such a vessel. Modern exploration cruise vessels typically need to be able to cope with extremely tough weather conditions, while having good virtual anchoring capacity and the option to disembark people and take them ashore. This means ships are often equipped with stabilising fins effective not only at speed but also during dynamic positioning, as well as large open embarkation platforms. As the vessel could be surrounded by ice at any time, the ship still needs to perform well even with its

Thorough model testing required to make cruising in tough environments sustainableThe exploration cruise sector is an expanding market with tough requirements. Modern exploration cruise vessels are designed with the user experience in mind, with the option to disembark people and take them ashore via kayaks and RIBs. Of course, the environmental impact and safety at sea are also paramount, and vessels need to be designed to cope with extremely rough weather conditions and harsh environments. A state­of­the art­vessel of this type is Ulstein’s new exploration cruise vessel design. SSPA was chosen as the hydrodynamic testing partner, which included traditional calm­water towing tank tests and tests in our seakeeping basin, both under way and at zero speed. Extensive Compu­tational Fluid Dynamics (CFD) simulations were performed. An important part of testing was to correlate these calculations with the model tests. Together, we developed a testing programme to assess the behaviour of the vessel in the most typical operating conditions. During testing, both the pod design and testing parameters were changed. Our experts supported the Ulstein design team, so they could deliver the best solution for their customer, shipowner Lindblad Expeditions Holdings Inc.

fins folded and allow for the operation of kayaks and RIBs from the large aft and side platforms. This adds to the challenges faced by the desig­ners when developing a cruise vessel for these harsh environments.

Access to land is (fortunately) limited, which places a number of demands on the design of such a vessel. Only a limited number of visitors, fewer than 100, can be on land at the same time including the crew, forcing the owners to limit the size of the vessel. This in turn limits the number of operators, as ships need to wait for their turn to disembark their passengers and crew.

This leads to vessels that are very specific in size and capacity:• Minimising the environmental impact is

important. Specific fuel oil consumption (SFOC) and silent propulsion are two typical key focuses.

• Vessels are relatively small compared to other cruise ships.

• The hull needs to be reinforced against ice.• The vessel must have good seakeeping ability

to withstand tough weather conditions.• For passengers, the experience ashore is as

important as the experience onboard.• There is no quay to disembark people and these

operations must be able to be comfortably performed in environments that preclude the use of fin stabilisers, e.g. the presence of ice. Furthermore, these operations are performed with virtual anchoring (dynamic positioning capacity), using large platforms at the aft and on the side of the vessel for launching RIBs and kayaks.

Facilitating our customers’ journey to successNicolas Bathfield, Manager of Hydrodynamics and Stability at Ulstein Design & Solutions, oversaw hydrodynamic development with his design team. Together with SSPA, a test pro­gramme was developed to assess the behaviour of the vessel in the most typical operating conditions and with the aim of trying to conduct tests at the most critical resonance wave periods. During testing, both the pod design and testing parameters were changed.

We asked Nicolas Bathfield about this project and how he thinks SSPA can best support designers and shipowners.

The pod design was altered late in the testing phase due the Polar Class approval process and additional tests were carried out. Were you able to use the results from the first round?“This is why we need flexible partners. We work to time constraints that are tough to meet and a lot of work has to be done in parallel, instead of the sequential design spiral we are normally used to”, says Nicolas Bathfield. He continues, “Ulstein Design & Solutions is working hard to establish an agile design process that allows for adapting the design to new requirements or for solving unforeseen challenges that may arise in any project. This in turn requires our partners to be able adapt to these changes and help us continually improve our designs over the course of the project. The first round of testing was definitely not wasted: it was a benchmarking test

“The ocean model basin was crucial for

this type of project, and the delivery time too. Flexibility was also an important factor in our

decision.”

that gave us even more confidence in our CFD models, as our prediction was borne out in the test results with very good agreement!”

What was the most important goal to achieve with the tests?“Together with SSPA, we designed a testing procedure aimed at testing the ship under all critical conditions. We wanted to capture the behaviour of the vessel during natural roll and pitch periods to make sure we got a good understanding of the maximum accelerations and motions that passengers would experience onboard under a certain set of conditions. Model tests are expensive, so we have to limit the scope. The rest can be simulated.”

Is X-BOW an important feature of the design?“Yes, this helps to dampen movements signifi­cantly in head seas. We wanted to run extensive model testing in an ocean model basin to look at the behaviour of the X­BOW in terms of slamming, but also in combination with the aft platform. It was important to verify that in stern­quartering seas, the X­BOW’s volume

above waterline (it is not really a flare) helped dampen the combined roll and pitch motions induced by the wave meeting the extremely flat aft buttock lines that are typical of this type of vessel”, says Nicolas.

“I also believe that the shipowners, who assis­ted with the tests, were very pleased with what they saw during wave model testing.”

You are a former SSPA employee, did this have anything to do with the choice of model testing facility?“We chose the basin based on the model test programme we wanted to run – the ocean model basin proved to be a crucial element for this project and we had strict time constraints when we ordered the tests that SSPA were able to meet. We cannot allow our past experiences influence our choices. If anything, me being a former employee was a challenge for both sides, as I had strong opinions on how I wanted the test programme to be run”, says Nicolas.

“I particularly appreciated the support during the tender phase, when SSPA’s experts helped us define the best possible model testing programme

National Geographic Endurance The vessel is designed for polar expe-ditions, with a high ice class and polar vessel features with Ulstein’s signature X-BOW.

Total length: 124 metres

Beam: 21 metres

Displacement: Approximately 8,000 tonnes

Lindblad Expeditions Holdings Inc. is an expedition travel company that works in partnership with National Geographic to inspire people to explore and care about the planet.

Ulstein Group has 600 employees and is headquartered in Ulsteinvik, Norway. In total, Ulstein Verft has built more than 300 vessels, and more than 100 vessels designed with the X-BOW have been delivered.

How can SSPA support designers and shipowners?

• Calm-water performance

• Seakeeping and comfort analysis

• Cavitation and noise measurement

• Propeller noise analysis with Computational Fluid Dynamics (CFD)simulations

Matz BrownProject Manager

Matz graduated with an MSc from Chalmers University of Technology in 1979 before working

at Götaverken Arendal. He has also worked at Uddevallavarvet and was a teacher for several years. Matz has been at SSPA since 1997 and specialises in hull design and model testing for sailing yachts and fast vessels.

Contact information E-mail: matz.brown@sspa.se

Martin KjellbergSpecialist, Seakeeping & Manoeuvring

Martin graduated from Chalmers University of Technology with an MSc

in 2007 and a PhD in 2013. Since then he has been at SSPA, specialising in seakeeping and manoeuvring model testing, as well as numerical seakeeping analysis methods.

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

for our project. It was of utmost importance for us to make sure we gathered enough informa­tion during the limited time available for testing and avoided having to run any extra rounds of testing, which would have been costly. I think that together we succeeded in getting the most out of the tests while at the same time allowing the shipowner to be present during testing with their own film crew.”

“I know through experience that this can be really demanding, as safety, confidentiality and time constraints are hard to balance when there are lots of visitors on site during a testing round, especially if a film crew is present. I am grateful to SSPA for arranging this so my customer also had a great experience during the test sessions”, Nicolas concludes.

Ulstein Design & Solutions tested two vessels, one of which was the National Geographic Endurance. Illustration: Courtesy of Lindblad Expeditions.

14 Highlights 66 / 2019 – Manoeuvring and seakeeping simulations, and the importance of high-quality data

Knowing how a vessel will behave in certain conditions can help answer many questions, for example:• What is the operational window for ship­to­

ship transfer?• What size and number of tugs are needed for

safe berthing?• Will the vessel roll heavily in the forecasted

weather?• In what conditions can the ship be safely

moored?• What engine power is required to be on

schedule 98% of the time?

One way to address these types of questions is to use advanced simulations. At SSPA, we have developed a toolbox, called SEAMAN Simula­tion, which can provide a solution for the issues above and much more.

The SEAMAN Simulation toolbox For many decades, experts at SSPA have deve­loped well­known and advanced ship models, which have formed the basis for today’s simu­lations. The SEAMAN Simulation is a versatile manoeuvring and seakeeping simulation toolbox. It is based on a semi­empirical approach. This means that the models that form the simulation system are based on a combination of fundamen­tal physical principals and measurements of the properties to be modelled. This technique is not just used at SSPA, but is the dominant technique used worldwide for real­ and fast­time manoeuv­ring and seakeeping simulations.

The challenge with the semi­empirical method is that it is highly dependent on the quality of data that the models use. Access to relevant and validated mathematical models is always an im­portant factor for successful simulations. SSPA’s models originate from our comprehensive data­bases derived from model tests conducted over the last 75 years. Thanks to SSPA’s test facilities, and the development and use of CFD, such as

Shipflow from Flowtech International, we have access to extremely good data which supports the simulation models.

Data from a variety of areas are compiled in SEAMAN and this has resulted in a wide range of applications such as: • Manoeuvring prediction• Port and fairway manoeuvring studies• Seakeeping – motion and acceleration• Assessment of roll prevention devices, such

as stabilising fins and anti-roll tanks• Monte Carlo simulations: a fast­time simu­

lation where environmental and operational conditions are randomised according to statistic distributions

• Mooring safety assessment• Ship­to­Ship operations• Operation of ships in locks and narrow canals• etc.

Experts cooperate closely with clientsFor each simulation assignment, SSPA communi­cates with the client to ensure that the simulation has the right level of details regarding both accuracy and cost-efficiency. To ensure the app­ropriate level, there are several areas that SSPA will tailor to the client’s needs. Depending on where a project is in the design phase, delivery time, budget and precision requirements for the models, our experts can select what data sources shall be used.

If a short delivery time is requested, we can use parametric data from our databases for ship resistance, manoeuvring and seakeeping pro­perties. If the design details must be accurately reflected in the simulation model, a physical model test and/or CFD computation are recom­mended to determine the parameter input and model validation.

Manoeuvring and seakeeping simulations, and the importance of high-quality dataSimulations are an efficient tool for gaining valuable insights for decision-making. To perform high-quality ship simulations, high­quality input data is required. Without good input data, the output from the simulations will not be a reliable source of support for decision­making. Thanks to SSPA’s test facilities, and the development and use of Computational Fluid Dynamics (CFD), we have access to extremely good data which supports the simulation models in the SEAMAN Simulation toolbox.

Example of CFD computation of flow field around a ship in turn with rudder to starboard.

Erland WilskeSenior Specialist, Simulations

Erland graduated with MSc in Electronic Engineering from

Chalmers University of Technology in 1988. After graduation, he worked on research in opto-electronic sensors and developing software for cargo handling systems. He joined SSPA in 1994 and, since then, he has been involved in projects linked to the development and use of ship simulation tools.

Contact information E-mail: erland.wilske@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 installa-tions at Technip Norway, participating 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 soft - ware development infrastructure.

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

Using the correct input will give the correct outputShip model tests in SSPA’s Towing Tank, such as resistance and self­propulsion tests, provide important input data: resistance curve, wake fraction, trust deduction, speed­power prediction, etc. Using these tests, together with propeller open water tests where propeller thrust and torque characteristic are measured in different working conditions, an accurate simulation model of the propeller and hull in calm water can be obtained.

If wave performance data are needed, the wave makers at the end of the towing tank allow for tests to be carried out with head­on and following waves. These measurements provide information on added resistance in waves that can be used in the simulations. Along with wave statistics and engine data, these provide assessments of route performance in different operational profiles.

If manoeuvring properties are needed, for example for harbour manoeuvring prediction, captive tests in the towing tank are one way of obtaining ship data for the manoeuvring properties. The results are direct measurements of manoeuvring coefficients for hull and steering devices, including propeller side forces.

SSPA’s Maritime Dynamic Laboratory (MDL) is a facility that contributes to the important input for the simulation toolbox. Several syste­matic test series have been carried out in order to formulate models for manoeuvring in confined water such as bank and canal effects, and shallow water effects, including squat prediction. The most common tests are standard manoeuvring tests, such as turning circle and zig­zag tests, and seakeeping. The results of these tests can be used to tune and validate simulation models.

With the above high­quality input data, the simu­lation models can be used for predicting a wider range of test scenarios and producing complete manoeuvring documentation (e.g. a manoeuvring booklet according to IMO 601).

The seakeeping tests are used in the same way to validate and tune the model, and to expand the test matrix to include different speeds, headings, wave conditions, etc.

With high-quality input data, the simulation models can be used for predicting a wider range of test scenarios and producing complete manoeuvring documentation.

Maritime Dynamic Laboratory (MDL) contributes with important inputs to the simulations. In this ex-ample we perform tests with a free-sailing tanker in a generic S-shaped fairway with sloped banks.

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operations safer and more profitable, and they will become more successful as a crew, owners or operators.

Preparation and execution of the simulations are critical, but despite being done accurately, the results can be misleading if the input data are incorrect. If this is the case, incorrect con­clusions will be drawn, which can lead to costly design changes.

Over the years, SSPA has created tools and methods to ensure that both quantitative and qualitative results of the simulations can be reported to the client in a concise manner. We are now taking manoeuvring simulations online, providing an intuitive web­based interface for easy access to a powerful tool. Contact us to find out more.

16 Highlights 66 / 2019 – Manoeuvring and seakeeping simulations, and the importance of high-quality data

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By comparing the result with selected criteria and making projections based on an expected operational profile, the ship’s operability and overall seakeeping performance can be obtained.

Data from a variety of areas have been compiled in SEAMANSimulations are an efficient tool for obtaining a wide range of data regarding ship operations and ship handling, and the output can directly support ship owners, operators, harbour masters, etc. in their decision­making. As a ship designer, it is wise to ensure that manoeuvring and seakeeping properties are within acceptable limits at the design stage to avoid unnecessary surprises that can be extremely costly if not dealt with in time. Knowing how vessels will behave in certain conditions helps our clients to make the correct decisions. This knowledge will make their

We are now taking manoeuvring simulations online, providing an intuitive web-based interface for easy access to a powerful tool.

All photos and illustrations by SSPA.