General information
Open top or hatchless (container) ships are ships without hatch covers. This will decrease the loading and unloading times and increase the flexibility of the ship. Because heavy rain and shipping water implies large quantities of water inside the cargo holds, additional requirements are specified. The interim IMO guidelines, which were published in 1994, specify amongst others the allowable amount of water in the holds and the minimum pump capacity. These guidelines also specify seakeeping model tests in order to quantify the amount of water entering the cargo holds in severe weather conditions.
Open top or hatchless (container) ships are ships without hatch covers. This will decrease the loading and unloading times and increase the flexibility of the ship. Because heavy rain and shipping water implies large quantities of water inside the cargo holds, additional requirements are specified. The interim IMO guidelines, which were published in 1994, specify amongst others the allowable amount of water in the holds and the minimum pump capacity. These guidelines also specify seakeeping model tests in order to quantify the amount of water entering the cargo holds in severe weather conditions.
Services & Activities
The objective of the seakeeping test program is to determine whether the vessel complies with the MSC/Circular 608 Guidelines for open top container vessels. The IMO guidelines state that the maximum water ingress should not exceed the hatch opening area multiplied by 400 mm/hour. The IMO guidelines prescribe the model tests to be performed. The following conditions should be tested:
The objective of the seakeeping test program is to determine whether the vessel complies with the MSC/Circular 608 Guidelines for open top container vessels. The IMO guidelines state that the maximum water ingress should not exceed the hatch opening area multiplied by 400 mm/hour. The IMO guidelines prescribe the model tests to be performed. The following conditions should be tested:
- Following seas at minimum manoeuvring speed
- Stern quartering seas at minimum manoeuvring speed
- Beam seas in free drifting condition
- Bow quartering seas at maximum sustained speed
- Head seas at maximum sustained speed
The tests must all be done for a significant wave height of 8.5 m at the most unfavourable realistic wave period. To select the most unfavourable wave period and to determine the maximum sustained speed, preliminary calculations will be performed prior to the model tests. The tests must be performed at the maximum loaded draught.
Facilities & Tools
Open top seakeeping tests are tested in the following MARIN facilities:
Open top seakeeping tests are tested in the following MARIN facilities:
- Seakeeping & Manoeuvring Basin: seakeeping and manoeuvring tests
Prior to the compulsory seakeeping tests the most unfavourable wave period and maximum sustained speed for each heading is calculated with the following tools:
Experience
The list below gives a review of open top model tests carried out at MARIN:
The list below gives a review of open top model tests carried out at MARIN:
- 127 m Open Top, Rolldock (2006)
- Open top 1700 TEU Ice class 1A , De Hoop Lobith (2005)
- 134 m Open Top vessel, Damen Hoogezand (2001)
- 150 m Open Top, Howaldtswerke-Deutsche werft (1996)
- 250 m Open Top container vessel, Nedlloyd (1990)
Most recent Open top papers presented by MARIN:
(complete overview of papers can be found under Publications)
(complete overview of papers can be found under Publications)
On the mamoeuvrability of naval surface ships with respect to a new STANAG
Armaoglu, Eggers, Quadvlieg, van Coevorden, RINA warships, 2010
Calculation method to include water on deck effects
Carette, van Walree, proceedings ISSW, 2010
On the prediction of parametric roll
Gunsing and Dallinga, proceedings ISSW, 2010
A Verification And Validation Exercise For The Flow Over A Backward Facing Step
Eça, L., Vaz, G.N.V.B. and Hoekstra, M., V European Conference on Computational Fluid Dynamics (ECCOMAS CFD), 2010
Modelling The Effect Of Sloshing On Ship Motions
Bunnik, T.H.J. and Veldman, A. (University of Groningen), OMAE ASME 29th International Conference on Ocean, Offshore and Arctic Engineering, Shanghai, 2010
Armaoglu, Eggers, Quadvlieg, van Coevorden, RINA warships, 2010
Calculation method to include water on deck effects
Carette, van Walree, proceedings ISSW, 2010
On the prediction of parametric roll
Gunsing and Dallinga, proceedings ISSW, 2010
A Verification And Validation Exercise For The Flow Over A Backward Facing Step
Eça, L., Vaz, G.N.V.B. and Hoekstra, M., V European Conference on Computational Fluid Dynamics (ECCOMAS CFD), 2010
Modelling The Effect Of Sloshing On Ship Motions
Bunnik, T.H.J. and Veldman, A. (University of Groningen), OMAE ASME 29th International Conference on Ocean, Offshore and Arctic Engineering, Shanghai, 2010
Most recent Open top articles written for MARIN Report:
(complete overview of articles can be found under Publications)
(complete overview of articles can be found under Publications)
Pioneering purpose-built wind turbine installation vessels under test
Willemijn Pauw & Arjen Koop, MARIN Report, 2010
Pulling together in ROPES JIP
Henk van den Boom, MARIN Report, 2010
Taking on the challenge of risk assessment at sea
Yvonne Koldenhof, MARIN Report, 2010
Correlation of speed-power predictions by model tests
Michiel Verhulst, MARIN Report, 2010
Quantifying quality
Martijn van Rijsbergen, MARIN Report, 2010
Willemijn Pauw & Arjen Koop, MARIN Report, 2010
Pulling together in ROPES JIP
Henk van den Boom, MARIN Report, 2010
Taking on the challenge of risk assessment at sea
Yvonne Koldenhof, MARIN Report, 2010
Correlation of speed-power predictions by model tests
Michiel Verhulst, MARIN Report, 2010
Quantifying quality
Martijn van Rijsbergen, MARIN Report, 2010
Contact
For more information on how MARIN can help your organisation with open top vessels, please contact the Merchant vessel team at MerchantVessel@marin.nl
For more information on how MARIN can help your organisation with open top vessels, please contact the Merchant vessel team at MerchantVessel@marin.nl