Light weight vessels operation in brashed ice Magnus Burman [email protected]
About the project
Background Are light weight ships e.g. WFSV or passenger ships built in aluminium or FRP suitable for operation in winter climate? … and how do to manage such operations?
Project goal Gather and collect technical and operational experiences from existing organisations with light weight ships operating in winter conditions.
The knowledge base will be used for • Indicating limiting factors • Provide a background for in-depth studies, analyses and
development
Challenges
Rederi/Operatör Varv Fartygskonstruktör Myndighet/Klassällskap Materialtillverkare
• Many and diverse opinions • Various backgrounds • Different geographic locations • Lack of documentation
Lightweight ships in ice
Hull shape
Hull structure
Propulsion
Icing/Deicing
Cooling systems Damages
Operation adaptation
Interface ship/dock
Rules and regulations
Light weight ships and winter conditions
Based on 33 interviews
Hull shape
Foto: Lena Fosselius-Peterson
Foto: Swede Ship Marine
Mono hulls Catamaran Trimaran Foto: N-O-S
Mobimar
Propullsion systems
Fixed propeller / rudder
Water jet
Azimut / Pod / IPS
Bow propeller
Trim / Interceptors
Bild: Volvo Penta
Foto: Mats Hjortberg
Bild: Servogear Foto: Steelprop Finland OY
Foto: Johan Edvardsson
Operation adaptation for winter traffic
Winter traffic time table Shift of vessel Reallocation of stops Docking at night Ice channels Reverse manoeuvres Restrictions
Foto: Styrsöbolaget
Foto: Styrsöbolaget
Existing damages
Excessive wear bottom color Slashed bow fenders Holes in kind on aluminum vessels Damage to the bilge keels Damage to the attachment of the sonar Pressure damage on side planking close to the stern
Hose rupture of water jets Over heating of the main and auxiliary engines Dry running of the fire pump Cracks in the gel-coat and top-coat Damage to the propeller Dropped rudders Damage in gel-coat in FRP single shell
Poor statistics on ice damage due deficiencies in the
reporting system.
The class lacks experience when they do not rate these
ships for navigation in ice .
Rules and regulations
The most common regulations for small ships used by interviewed organisations are
• NBS-Y, Nordisk båtstandard för yrkesbåtar under 15 m 1990 (Sverige, Norge, Finland Danmark)
• Sjöfartsverkets Yrkesbåtsregler (Finnish Maritime Administration - Commercial Craft Rules) Version 2009:1 (Finland)
• Bekendtgørelse om Meddelelser fra Søfartsstyrelsen F, teknisk förskrifts om mindre erhvervsfartøjers bygning og udstyr m.v. (Danmark)
Regulation development
• National rules before class • Function based rules - concern about increased cost • One way forward might be two tracks
Light weight ship operation
in ice
Finska Sjöfartsverkets Yrkesbåtsregler
Function based rules for winter operation
Lightweight ships in ice
Hull shape
Hull structure
Propulsion
Icing/Deicing
Cooling systems Damages
Operation adaptation
Interface ship/dock
Rules and regulations
Light weight ships and winter conditions
Based on 33 interviews
Light weight vessels operation in brashed ice Magnus Burman & Niclas Niclasen
Lightweight operation in ice - motivation
Waterway will provide an capacity increase in public transport
Light weight and high speed vessels is part of a sustainable transport system
Few (if any) publication on interaction ice and lightweight (high speed) ships
Operator experience – no problem
Unverified opinions dominate the debate on light weight FRP vessels operating in ice
More information – www.waterway365.com
Operational profile – Stockholm
Waterway Subway Commuter train
The vessel
Ice loading – ice thickness
Ice impact model
15 20 25 30 35 401.3
1.4
1.5
1.6
1.7
1.8
1.9
2Impact velocity, as a function of speed
Vessel speed in [kn]
Ve
loci
ty n
orm
al t
o p
an
el a
t im
pa
ct in
[m
/s]
15.5 16 16.5 17 17.5 18−1
−0.5
0
0.5
Impact location, Speed:25[kn], Draft:1.68[m], Trim:5.51[deg]
Impact velocity:1.32[m/s]
x−coordinate, forward of end of keel [m]
z−co
ord
inate
, w
ate
rlin
e is
0 [m
]
WaterlineKeel lineIce floe1/3 impact velocity
Panels
Bröderna Aa Docksta Shipyard
Test series
Rigid steel plate – impact speed variation (mass constant) – impact mass variation (speed constant)
Aluminium panel 1 – impact speed variation (mass constant) Aluminium panel 2 – impact mass variation (speed constant)
Carbon panel – impact mass variation (speed constant)
Mass – 215, 300, 400, 500, 600 kg Speed – 1.50, 1.77, 2.05, 2.29, 2.51 m/s
(Corresponding kenitic energy in impact)
Making of ice
Ice cone geometry Ice structure analysis
Crushed ice + water + cold Ice test block
Freeze from bottom and up to avoid cracking
-26°C
Ice
Insulation
Impactor geometry
−50 0 50 100 150 200 250 300 350 400 450−20
0
20
40
60
80
100
120
Forc
e on
bas
e [k
N]
Miliseconds from impact
Test name: R1 Time of impact: 20−Oct−2015 16:22:42.454
−50 0 50 100 150 200 250 300 350 400 450−5
0
5
10
15
20
25
30
Force o
n base
[kN]
Miliseconds from impact
Test name: R3C Time of impact: 21−Oct−2015 12:50:55.320
Initial test series to evaluate ice cylinder
Pea
k fo
rce
Impact setup
Ice impactor
Pressure mapping film
Markings for indentation measurements
Ice impactor
Impact weight
High speed camera
Rigid steel panel Aluminium panel 1.5 m/s, 215 kg
Carbon fibre sandwich panel Aluminium panel 1.5 m/s, 215 kg
Fracture surface vs pressure mapping
Indentation measurements
Laser
Rail
Indication lines for measurements
Deformation Aluminium
−500
0
500
−500
0
500−15
−10
−5
0
5
Position on panel in x−direction [mm]
Relative deformation of panel 2 AM after test AM3C
Position on panel in y−direction [mm]
Def
orm
atio
n [m
m]
Position 1, Minimum: −4.79Position 2, Minimum: −12.38Position 3, Minimum: −4.55Location of min
−400 −300 −200 −100 0 100 200 300 400−15
−10
−5
0
5
Def
orm
atio
n [m
m]
Position on panel in x−direction [mm]
Relative deformation of panel 2 AM at position 2
AMbaAM0C, Minimum: −6.95 mmAM1C, Minimum: −10.90 mmAM2C, Minimum: −11.26 mmAM3C, Minimum: −12.38 mmAM4C, Minimum: −12.31 mmLocation of min
Deformation CFRP sandwich
−400 −300 −200 −100 0 100 200 300 400−15
−10
−5
0
5
Def
orm
atio
n [m
m]
Position on panel in x−direction [mm]
Relative deformation of panel 3 CM at position 2
CMBCM0, Minimum: −0.90 mmCM1, Minimum: −2.26 mmCM2, Minimum: −1.97 mmCM3, Minimum: −2.08 mmCM4, Minimum: −2.57 mmLocation of min
Max force / load readings
Load is sum of measurement from the four load cells under the panel
−0.05 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.450
5
10
15
20
25
30
35
40
45
50
Time [s]
Forc
e [k
N]
Test CM0, 225 kg, Max: 25.6 kN
Load cells
Ice fracture vs no ice fracture
−0.05 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.450
5
10
15
20
25
30
35
40
45
50
Time [s]
Forc
e [k
N]
Test CM2, 407 kg, Max: 32.6 kN
Load cells
−0.05 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.450
5
10
15
20
25
30
35
40
45
50
Time [s]
Forc
e [k
N]
Test CM1, 304 kg, Max: 32.9 kN
Load cells
300 kg, 1.5 m/s 400 kg, 1.5 m/s
Forc
e [k
N]
Forc
e [k
N]
Peak force – different settings Aluminium panel
0
5
10
15
20
25
30
35
40
1 2 3 4 5
Forc
e [k
N]
AV
AM
Aluminium panel 1 – impact speed variation (mass constant) Aluminium panel 2 – impact mass variation (speed constant)
Aluminium panel
0
200
400
600
800
1000
1200
1 2 3 4 5
Ener
gy [J
]
Energy Max
AV
AM
Aluminium panel 1 – impact speed variation (mass constant) Aluminium panel 2 – impact mass variation (speed constant)
Lightweight operation in ice
Waterway will provide an capacity increase in public transport
Light weight and high speed vessels is part of a sustainable transport system
Few (if any) publication on interaction ice and lightweight (high speed) ships
Operator experience – no problem
Unverified opinions dominate the debate on light weight FRP vessels operating in ice