General information
RoRo's, RoPax, Container vessels and cruise vessels sail according a fixed schedule. Therefore, it is important to know if these vessels are able to keep their schedule.
Wind, waves and current cause additional resistance with respect to the calm water resistance. This so-called added resistance, increases the power demand. If the demand is higher than the capacity of the engine the ships speed decreases. This is called "involuntary" speed loss. The ships master can also reduce the velocity because of comfort and (fear for) damage to ship and cargo. This is called "voluntary" speed reduction.This comfort and damage issues can be related to slamming, green water and whipping and springing of the hull.
RoRo's, RoPax, Container vessels and cruise vessels sail according a fixed schedule. Therefore, it is important to know if these vessels are able to keep their schedule.
Wind, waves and current cause additional resistance with respect to the calm water resistance. This so-called added resistance, increases the power demand. If the demand is higher than the capacity of the engine the ships speed decreases. This is called "involuntary" speed loss. The ships master can also reduce the velocity because of comfort and (fear for) damage to ship and cargo. This is called "voluntary" speed reduction.This comfort and damage issues can be related to slamming, green water and whipping and springing of the hull.
Services & Activities
Schedule reliability can be assessed by means of scenario simulations. During these simulations (round)trips are simulated stepwise. Each trip is simulated for hundreds of times and for several years. At each time step the maximum sustained speed is calculated accounting for engine limitations and the actual weather conditions. Furthermore the ship behaviour is evaluated and this input is used to asses "voluntary" speed reduction.
The duration of each trip is obtained for every voyage. The long term distribution of these durations is used to obtain the required service margin (see figure above). It also can account easily for seasonal variations.
Schedule reliability can be assessed by means of scenario simulations. During these simulations (round)trips are simulated stepwise. Each trip is simulated for hundreds of times and for several years. At each time step the maximum sustained speed is calculated accounting for engine limitations and the actual weather conditions. Furthermore the ship behaviour is evaluated and this input is used to asses "voluntary" speed reduction.
The duration of each trip is obtained for every voyage. The long term distribution of these durations is used to obtain the required service margin (see figure above). It also can account easily for seasonal variations.
Facilities & Tools
Schedule reliability is assessed by the Safetrans and Gulliver software tools. Details on these tools can be found here.
Schedule reliability is assessed by the Safetrans and Gulliver software tools. Details on these tools can be found here.
Most recent Schedule reliability papers presented by MARIN:
(complete overview of papers can be found under Publications)
(complete overview of papers can be found under Publications)
Research into the Effects of Motion Simulation on Tugboat Captain Training and Performance in Bridge Simulators
D. ten Hove and M. Roza, HPAS2010: Human Performance At Sea, 2010
Analysis of the Tunnel Immersion for the Busan-Geoje Fixed Link Project Through Scale Model Tests and Computer Simulations
Hans Cozijn (MARIN) and Jin Wook Heo (Daewoo Engineering and Construction, Ltd.), OMAE Conference, Honolulu, 2009
Bow flare slamming of container ships and it's impact on operational reliability
R. P. Dallinga, RINA, 2006
Real Time Data for Structural Integrity and Stability Assessment: A GoM Case Study
Mitchell, M., Tipton, E., van Dijk, R.R.T. (MARIN) and Allen, B., Society of Petroleum Engineers (SPE), 2006
The Behaviour of Tugs in Waves Assisting LNG Carriers During Berthing Along Offshore LNG Terminals
Bas Buchner, Pieter Dierx and Olaf Waals, OMAE Conference, Halkidiki, 2005
D. ten Hove and M. Roza, HPAS2010: Human Performance At Sea, 2010
Analysis of the Tunnel Immersion for the Busan-Geoje Fixed Link Project Through Scale Model Tests and Computer Simulations
Hans Cozijn (MARIN) and Jin Wook Heo (Daewoo Engineering and Construction, Ltd.), OMAE Conference, Honolulu, 2009
Bow flare slamming of container ships and it's impact on operational reliability
R. P. Dallinga, RINA, 2006
Real Time Data for Structural Integrity and Stability Assessment: A GoM Case Study
Mitchell, M., Tipton, E., van Dijk, R.R.T. (MARIN) and Allen, B., Society of Petroleum Engineers (SPE), 2006
The Behaviour of Tugs in Waves Assisting LNG Carriers During Berthing Along Offshore LNG Terminals
Bas Buchner, Pieter Dierx and Olaf Waals, OMAE Conference, Halkidiki, 2005
Most recent Schedule reliability articles written for MARIN Report:
(complete overview of articles can be found under Publications)
(complete overview of articles can be found under Publications)
MARIN gets to grip with the elusive Human Factor
As the maritime industry recognises the importance of the human factor, MARIN has taken the decision to step into this new and highly complex field.
Model tests for early assessment of Launch and Recovery operations
DCNS chose MARIN to conduct an operability study of the Launch and Recovery system to be installed on the new GOWIND type Offshore Patrol Vessels (OPV) that are currently under construction.
Safetrans celebrates 10th anniversary!
With the release of SafeTrans 5 and the active participation of the Safetrans members, it now becomes clear that SafeTrans will be the ‘de facto’ standard for the marine transportation industry. Report outlines a decade of...
INPEX's eternal flame in Indonesian Arafura Sea
During drilling of the first exploration well in 2000, the Japanese operator INPEX discovered a large gas accumulation in the Masela block in the Indonesian Arafura Sea. Subsequent drillings in 2002 confirmed that the gas find...
The flight of the condor
A Condor computer cluster is increasingly frequently being used to help analyse downtime events in the LNG sector. Report explains this new method.
As the maritime industry recognises the importance of the human factor, MARIN has taken the decision to step into this new and highly complex field.
Model tests for early assessment of Launch and Recovery operations
DCNS chose MARIN to conduct an operability study of the Launch and Recovery system to be installed on the new GOWIND type Offshore Patrol Vessels (OPV) that are currently under construction.
Safetrans celebrates 10th anniversary!
With the release of SafeTrans 5 and the active participation of the Safetrans members, it now becomes clear that SafeTrans will be the ‘de facto’ standard for the marine transportation industry. Report outlines a decade of...
INPEX's eternal flame in Indonesian Arafura Sea
During drilling of the first exploration well in 2000, the Japanese operator INPEX discovered a large gas accumulation in the Masela block in the Indonesian Arafura Sea. Subsequent drillings in 2002 confirmed that the gas find...
The flight of the condor
A Condor computer cluster is increasingly frequently being used to help analyse downtime events in the LNG sector. Report explains this new method.
Contact
For more information on how MARIN can help your organisation with schedule reliability assessments, please contact:
Seakeeping Department
For more information on how MARIN can help your organisation with schedule reliability assessments, please contact:
Seakeeping Department