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Oil Spill Information System: OSIS • Spill trajectory and weathering prediction
tool
• Based on 25 years of laboratory work into oil spills
• Validated against 18 sea trial spills (see picture) and real life incidents (Sea Empress, Rose Bay, Braer)
• GIS-based, designed for use by spill responders and consultants
• Contains >120 oil types, laboratory analysed for weathering and dispersibility
• Underlying databases of oceanography and maps for rapid set-up
• Works on laptop, PC and potential to operate on LAN or Internet
OSIS Outputs
• GIS-based outputs showing slick trajectory, spread and contours of thickness or dispersed concentrations
• Status panels showing spill volume, viscosity, flash point
• Beaching locations
• On screen graphs track history of volumes, viscosity, flash point
Shoal • An intelligent AUV team to monitor pollution in seaports and harbours.
• Developments in AI, Robotics, Communications and Sensors.
• Evaluation and Testing in Gijon.
Concepts evaluated
ROPAX Curtain
Internal Double bottom installation
Deployable salvage tool
The development of a combination of satellite booster technology with air pressure systems and balloon technology to create a multi purpose modular system for ship rescue purposes.
Fishing vessel
Technical Details / Work done in period 1
Fitting arrangement Bars are envisioned to be rigidly attached to the inner structure of the ship Or be stored with the balloon on (or below) the car deck and be lifted as the balloon inflates
bars
balloon
Steel bars
balloon
DESCRIPTION OF TASK 2.3 Curtain Concept
Technical Details / Work done in period 1
Fitting arrangement Bars are envisioned to be rigidly attached to the inner structure of the ship Or be stored with the balloon on (or below) the car deck and be lifted as the balloon inflates
bars
balloon
Steel bars
balloon
DESCRIPTION OF TASK 2.3 Curtain Concept ROPAX Curtain concept
ROPAX Curtain concept
Technical Details / Work done in period 1
Conclusion
¾Curtain doesn’t hold even with cables of 16 mm diameter and plate material of steel. ¾Hydrostatic loads are way less than hydrodynamic loads. ¾Textile thickness seems to be the most detrimental property for structural integrity
DESCRIPTION OF TASK 2.3 Curtain Concept
• Curtain doesn’t hold even with cables of 16mm diameter.
Salvage concept
• HAZID analysis completed
• Evaluation of shear forces and bending moments and corresponding fatigue damage thresholds
• Live Testing.
Single Input Fuzzy Sliding Mode
Controller(SIFSMC)
Sliding mode controller
Time (s)
0 100 200 300 400 500 600 700 800 900 1000
z (m
)
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30 m40 m50 m
Time (s)
0 100 200 300 400 500 600 700 800 900 1000
w (m
/s)
0.00
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
30 m40 m50 m
Time (s)
0 100 200 300 400 500 600 700 800 900 1000
θ (d
eg.)
-4.5
-4.0
-3.5
-3.0
-2.5
-2.0
-1.5
-1.0
-0.5
0.0
30 m40 m50 m
Time (s)
0 100 200 300 400 500 600 700 800 900 1000
q (ra
d/s)
-0.0003
-0.0002
-0.0001
0.0000
0.0001
0.0002
30 m40 m50 m
Table 1: Input parameters in the simulation program
Parameters Values & Units W 9320 kg l 6.0 m b 3.0 m ρ 1025 kgm-3
ρg 1.017 kgm-3
Iyy 1481.31 kgm2 wZ "& - 15.7x 10-3
qZ "& - 0.41x10-3
wM "& - 0.53x10-3
qM "& - 0.79x10-3
Some input physical and empirical parameters are given in Table 1 for the pontoon model. The inflation time of filling gas inside the balloons depends on the initial flow rate whereas the breakout time of the pontoon from the seafloor is assumed to be 100 s. The latter would be changed if the appropriate suction force model was considered. In the following, two cases of numerical simulations are considered for different target depths being equal to 30, 40 and 50 m. In the first case, the initial flow rate is variable for different depths, whereas in the second case the initial flow rate is fixed. The latter would result in different numerical simulation time depending on the sliding-mode control. 4.1 CASE 1: VARYING INITIAL FLOW RATE With 3 target (30, 40 and 50 m) depths, 3 different initial flow rates (0.15, 0.1875 and 0.25 m3s-1, respectively) are considered such that the payload reaches the desired depths at the same time (about 1000 s). The inflation time of filling gas inside the balloons is suitably taken as 100, 80 & 60 s respectively. The obtained vertical dynamic responses (vertical trajectory, ascent velocity, pitch angle and pitch rate) and the variation of the control parameter (i.e. the flow rate) are presented in Figures 4-7 and 8, respectively.
Figure 4: Case 1 - Variation of ship vertical position
Figure 5: Case 1 - Variation of ship ascent velocity
Figure 6: Case 1 - Variation of ship pitch angle
Figure 7: Case 1 - Variation of ship pitch rate
It is worth noting that the ascent velocity of a raising vessel is vital to the successful salvage operation. This entails a comparatively slow process (about 17 min in the present case). It is seen from Figure 5 that the maximum heave velocity (ascent velocity) increases with the target depth as does with the initial flow rate. The maximum
Time (s)
0 100 200 300 400 500 600 700 800 900 1000
z (m
)
0
5
10
15
20
25
30
35
40
45
50
30 m40 m50 m
Time (s)
0 100 200 300 400 500 600 700 800 900 1000
w (m
/s)
0.00
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
30 m40 m50 m
Time (s)
0 100 200 300 400 500 600 700 800 900 1000
θ (d
eg.)
-4.5
-4.0
-3.5
-3.0
-2.5
-2.0
-1.5
-1.0
-0.5
0.0
30 m40 m50 m
Time (s)
0 100 200 300 400 500 600 700 800 900 1000
q (ra
d/s)
-0.0003
-0.0002
-0.0001
0.0000
0.0001
0.0002
30 m40 m50 m
Table 1: Input parameters in the simulation program
Parameters Values & Units W 9320 kg l 6.0 m b 3.0 m ρ 1025 kgm-3
ρg 1.017 kgm-3
Iyy 1481.31 kgm2 wZ "& - 15.7x 10-3
qZ "& - 0.41x10-3
wM "& - 0.53x10-3
qM "& - 0.79x10-3
Some input physical and empirical parameters are given in Table 1 for the pontoon model. The inflation time of filling gas inside the balloons depends on the initial flow rate whereas the breakout time of the pontoon from the seafloor is assumed to be 100 s. The latter would be changed if the appropriate suction force model was considered. In the following, two cases of numerical simulations are considered for different target depths being equal to 30, 40 and 50 m. In the first case, the initial flow rate is variable for different depths, whereas in the second case the initial flow rate is fixed. The latter would result in different numerical simulation time depending on the sliding-mode control. 4.1 CASE 1: VARYING INITIAL FLOW RATE With 3 target (30, 40 and 50 m) depths, 3 different initial flow rates (0.15, 0.1875 and 0.25 m3s-1, respectively) are considered such that the payload reaches the desired depths at the same time (about 1000 s). The inflation time of filling gas inside the balloons is suitably taken as 100, 80 & 60 s respectively. The obtained vertical dynamic responses (vertical trajectory, ascent velocity, pitch angle and pitch rate) and the variation of the control parameter (i.e. the flow rate) are presented in Figures 4-7 and 8, respectively.
Figure 4: Case 1 - Variation of ship vertical position
Figure 5: Case 1 - Variation of ship ascent velocity
Figure 6: Case 1 - Variation of ship pitch angle
Figure 7: Case 1 - Variation of ship pitch rate
It is worth noting that the ascent velocity of a raising vessel is vital to the successful salvage operation. This entails a comparatively slow process (about 17 min in the present case). It is seen from Figure 5 that the maximum heave velocity (ascent velocity) increases with the target depth as does with the initial flow rate. The maximum
Variation in assent velocity Variation in pitch angle
Time (s)
0 100 200 300 400 500 600 700 800 900 1000
z (m
)
0
5
10
15
20
25
30
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30 m40 m50 m
Time (s)
0 100 200 300 400 500 600 700 800 900 1000
w (m
/s)
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f (m
3 /s)
0.00
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value of the ascent velocity is found to be 0.08 m/s - being within the required range (< 0.6 m/s [5]). This implies how the pontoon motion is stable. When the vessel reaches the commanded depth, the controller reduces the ascent velocity to the nearly-zero value. The depth rate and ascent velocity responses reveal similar trend to the results of Nicholls-Lee et al. [2].
Figure 8: Case 1 - Variation of gas flow rate
From Figure 6, the pitch angle is found to increase with time, reaching a maximum value during a half of period and thereafter decreasing. The maximum value of the pitch angle is found to be about 4.2 deg. which is within the required limit (< 15 deg. [5]). Similar to the ascent velocity in Figure 5, the pitch angle in Figure 6 increases with the initial input flow rate. Nevertheless, the pitch angle decreases when the payload reaches the commanded depth due to the fact that the controller generates a pitch angle command as per the depth error. At the beginning, the depth error is large thereby the controller produces a high value of pitch angle to eliminate the error. Figure 7 shows how the pitch rates of all analysis depths become nearly equal to zero when the pontoon reaches the required positions. In all three depth (30, 40 and 50 m) cases, it is seen from Figure 8 that soon after the breaking out period (at t = 100 s) the sliding-mode controller instantly reduces the initial input flow rate value from 0.15, 0.1875 and 0.25 to 0.092, 0.116 and 0.15 m3s-1, respectively, in order to compensate the presence of excessive buoyancy induced by a sudden release of the pay load from the sea bottom. Thereafter, the flow rate of gas filling maintains a constant value until the vessel nearly reaches the target depth. Once the target depth is fulfilled, the controller further reduces the flow rate to almost the zero value. The variation in the buoyancy force with respect to the varying depth is compensated by the pressure relief valves. Thus, by the combined use of the sliding mode controller for regulating the flow rate of filling and pressure relief valves, a constant and stable ascent rate can be reasonably maintained.
4.2 CASE 2: FIXED INITIAL FLOW RATE Now, the analysis is performed in the case of fixed initial flow rate (0.25 m3s-1) for different target depths. The simulation times required for the depths of 30, 40 and 50 m are 700, 800 and 1000 s, respectively. The obtained dynamic responses are displayed in Figures 9-13. It can be seen from Figures 9-12 that the obtained responses are stable (based on the limiting values of ascent velocity and pitch angle). They are also quite similar to those illustrated in Figures 4-7. The maximum ascent velocity, pitch angle and pitch rate values seem to depend mainly on the initial input flow rate, irrespective of the simulation time. After the pontoon reaching the commanded target depth, even though the simulation time is variable, it has a slight effect on the response values because of the sliding-mode controller action. As a result, Figure 13 displays 3 different patterns – i.e. reduction, maintenance and further reduction to zero value – of the flow rate, as in Figure 8.
Figure 9: Case 2 - Variation of ship vertical position
Figure 10: Case 2 - Variation of ship ascent velocity
Time (s)
0 100 200 300 400 500 600 700 800 900 1000
θ (d
eg.)
-4.5
-4.0
-3.5
-3.0
-2.5
-2.0
-1.5
-1.0
-0.5
0.0
30 m40 m50 m
Time (s)
0 100 200 300 400 500 600 700 800 900 1000
q (ra
d/s)
-0.0003
-0.0002
-0.0001
0.0000
0.0001
0.0002
30 m40 m50 m
Time (s)
0 100 200 300 400 500 600 700 800 900 1000
f (m
3 /s)
0.00
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Figure 11: Case 2 - Variation of ship pitch angle
Figure 12: Case 2 - Variation of ship pitch rate
Figure 13: Case 2 - Variation of gas flow rate
It should be noted that the present preliminary model and numerical results are based on the rigid-body ship behaviour and several assumptions. This could be further improved by considering, for instance,
• the appropriate breakout force model in order to evaluate the suitable breakout time,
• the effect of surge degree of freedom: this would however lead to some nonlinear coupling terms which require a nonlinear control strategy such as a Fuzzy or Adaptive sliding-mode controller,
• the elastic beam model with free–free boundary conditions for the ship to account for the spatial variation of hydrodynamic forces, moments and pressures as well as ship displacements and velocities,
• the evaluation of shear forces and bending moments and corresponding fatigue damage thresholds.
5. CONCLUSIONS A mathematical modelling and numerical time-domain approach to simulate the dynamics of a sunken vessel being raised from the seafloor by a gas inflating system have been presented. Some preliminary parametric studies have been carried out and the obtained numerical results highlight the following findings.
• The flow rate of filling gas inside the balloon is the key parameter determining the ship stability during the raising dynamics.
• For a safe and viable salvage operation, the
ascent velocity and pitch angle should be controlled by the combined use of sliding mode controller and pressure relief valve.
• The sliding mode controller may be utilized to
effectively maintain the hydrodynamic stability of the raising vessel in the diving plane during the salvage operation.
6. ACKNOWLEDGEMENTS This work is part of the SuSy (Surfacing System for Ship Recovery) project funded by the European Commission FP7 framework (www.su-sy.eu). We are very grateful for this support. We also wish to dedicate this paper to our late colleague Dr K Varyani who was involved in this project. 7. REFERENCES 1. U.S. Navy, ‘Salvage Engineer’s Handbook’
Volume1, 1992. 2. Nicholls-Lee, R.F., Turnock ,S.R., Tan, M.,
McDonald, P,C.,Shenoi, R.A.,’Use of cryogenic buoyancy systems for controlled removal of heavy objects from sea bottom’, Proceedings of the ASME 28th International Conference on Ocean ,Offshore & Arctic Engineering, 2009.
For a safe and viable salvage operation, the ascent velocity and pitch angle should be controlled by the combined use of an adaptive fuzzy sliding mode controller and pressure relief valve
FSMCs shows 30 % of improvement in tracking performance over SMC. SIFSMC is proved to be the preferred option among these controllers with less tuning effort and computational time.
Live testing soon
Double bottom concept DPAM – Method
• Stress Intensity Factors evaluation • Bottom Damage – Grounding • Side and Deck Damages - Collision
• Crack Propagation Equation • Resolution of a differential equation
• Implementation : Octave script
4.9813 m
Double bottom concept Concept overview
Prediction of structural integrity time as decision making tool. Optimisation of the loads to increase the Structure Integrity Time.
• Ballasts • Tanks • Additional buoyancy due to SuSy balloon system
School of Naval Architecture and Marine Engineering Shipbuilding Technology Laboratory
Description of Damage control cases applied to the damage vessel
Ballast
• Ballasting the double skin and hopper tanks opposite to the damaged ones.
SuSy Devices
• Attachment points of SuSy devices on bulkheads.
SuSy Devices
• Attachment points of SuSy devices on both webs and bulkheads.
Damage Scenario
2nd Case
Loading case B1-100% Sagging of the Common Structural Rules for Oil-Tankers.
Rectangular damage • 10m longitudinal • 5.5m above WL • 8.5m below WL
School of Naval Architecture and Marine Engineering Shipbuilding Technology Laboratory
Results
Remarks • Cases (a) & (b) similar stress
distribution. • Case (a) slightly higher stress
distribution on deck. • Case (c) lower stress distribution
below damage area.
Double bottom concept
School of Naval Architecture and Marine Engineering Shipbuilding Technology Laboratory
Results
Remarks • Cases (a) & (b) similar stress distribution. • Case (c) lower stress distribution. • Average stresses for case (c) more than 50% lower than cases (a) & (b)
Double bottom concept
•The application of SuSy devices on both bulkheads and webs compared to ballasting, exhibits over 50% less average stresses, on hopper plating, relevant longitudinal stiffeners and side skin, situated on the damaged side.
•Between the upper deck and upper section of damage, SuSy cases exhibits slightly lower stress distribution than the cases where the SuSy devices are applied.
•Proper selection of attachment points for the SuSy devices is essential regarding structural response of the damaged compartment
Design update
• A"achment lacing set to the maximum length to reduce the
balloon movement during infla7on. • Addi7onal s7ffener behind clamping bar to provide mechanical resistance
against slipping. • Addi7onally both rubber faces will be buffed to improve fric7on inside the
clamping area. • The thickness of the clamping bar will
be of 6mm and made of steel.
• The packed balloon will be geAng longer, but more slim.
• All contact areas of the balloon to the s7ffeners will be reinforced by applying a
second layer of material.
Thank you
Dr. Benjamin Hodgson Senior Research Scientist
BMT Group Ltd,
Goodrich House, 1 Waldegrave Road
Teddington, Middlesex, TW11 8LZ, UK
Tel: +44 (0) 20-8614-4216
http://www.su-sy.eu/
CISE & e-maritime Example of information layers (non-hierarchical)
11
C O M M U N I C A T I O N
a cost effective decentralised interconnection of different information layers that increases efficiency of maritime surveillance systems by filling existing information gaps across Europe while avoiding data duplication.
These layers are managed by the respective owners of related information at Member States and EU level based on the applicable legal instruments. The competences of national authorities, as well as the mandates of EU Agencies set out in these legal instruments will thus be fully respected.
Common needs to most of the User Communities are to obtain an enhanced basic maritime situation awareness picture useful to all user communities. This picture may be composed by data stemming from a combination of systems and sensors detecting cooperative and non cooperative targets of any size.
Data of this basic maritime traffic picture is not clas-sified and could be shared without any restrictions between all Communities provided the necessary safeguards are put into place.
The discussions in the MS Expert Group concluded that this roadmap should lead to the creation of a decentralised information exchanging system, interlinking all User Communities both civilian and military. The setting up of the CISE should be a flexible process allowing for technical improve-ments and sectoral enhancements. Existing and planned systems shall be duly taken into account while developing the CISE. This process shall also not hinder the development of existing and planned sectoral information systems, as long as the need for interoperability enabling information exchange with other systems is taken into account. The expe-rience gained from information exchange systems allowing for civil-military cooperation should be utilised.
Considering the significant number of potential par-ticipants in the CISE, the diversity of legal frame-works and possible exchanges, it is highly unlikely that one single technical solution will fit each and every exchange of information within the CISE. For this reason the CISE architecture should be designed as
2| Overview of the roadmap
Fishery control
Maritime authority
Defence
Internal security
Information sharing
National authorities
VMS
SAFESEANET
PT MARSUR
EUROSUR
User-defined COP
Information layers
Common information sharing environment
Secretary of States Representative for Maritime Salvage and Intervention – (SOSREP) oversee, control and if necessary to intervene and exercise “ultimate command and control”, acting in the overriding interest of the United Kingdom in salvage operations within UK waters involving vessels or fixed platforms where there is significant risk of pollution.
SOSREP should be: • On site, able to act without delay • Free to act without recourse to higher authority.
• The involvement of Ministers in operational decisions is not a practical option. • The “Trigger Point” for Intervention is when there is a significant threat
of pollution to the UK’s pollution control zone, territorial waters or coastline.
• By not issuing a direction the SOSREP is adopting and approving the proposed course of action proposed by those dealing with the incident.
Oxfam donut
A Safe and Just Space for Humanity Oxfam Discussion Paper, February 2012 ��
EXECUTIVE SUMMARY�This Discussion Paper sets out a visual framework for sustainable development – shaped like a doughnut – by combining the concept of planetary boundaries with the complementary concept of social boundaries.
Achieving sustainable development means ensuring that all people have the resources needed – such as food, water, health care, and energy – to fulfil their human rights. And it means ensuring that humanity’s use of natural resources does not stress critical Earth-system processes – by causing climate change or biodiversity loss, for example – to the point that Earth is pushed out of the stable state, known as the Holocene, which has been so beneficial to humankind over the past 10,000 years.
In the lead-up to the UN Conference on Sustainable Development in June 2012 (known as Rio+20), and the High-Level Summit on the Millennium Development Goals in 2013, there is a growing debate on how to draw up renewed and expanded global development goals which bring together the twin objectives of poverty eradication and environmental sustainability.
Figure I below brings them into a single framework. The social foundation forms an inner boundary, below which are many dimensions of human deprivation. The environmental ceiling forms an outer boundary, beyond which are many dimensions of environmental degradation. Between the two boundaries lies an area – shaped like a doughnut – which represents an environmentally safe and socially just space for humanity to thrive in. It is also the space in which inclusive and sustainable economic development takes place.
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Source: Oxfam. The 11 dimensions of the social foundation are illustrative and are based on governments’ priorities for Rio+20. The nine dimensions of the environmental ceiling are based on the planetary boundaries set out by Rockström et al (2009b)�