General information
One of the important mean environmental loads on offshore structures are the current loads, especially in regions with strong currents, such as the Gulf of Mexico. In high current velocities the current loads on the floater can be significant. Many floaters (such as FPSOs) only experience the surface current velocity, but for deep draft floaters (such as spars) the vertical current velocity profile also needs to be considered.
One of the important mean environmental loads on offshore structures are the current loads, especially in regions with strong currents, such as the Gulf of Mexico. In high current velocities the current loads on the floater can be significant. Many floaters (such as FPSOs) only experience the surface current velocity, but for deep draft floaters (such as spars) the vertical current velocity profile also needs to be considered.
Services & Activities
The Offshore Department has a lot of expertise in the field of current loads on FPSOs, Semi-submersibles and Spars. Current loads can be measured in one of MARIN's basins, either by generating current in the basin or by towing the structure. Alternatively, the current loads can be determined by means of wind tunnel tests, carried out at the facilities of one of our regular sub-contractors. Possibilities for the calculation of current loads include the use of data base current load coefficients (using measurement results for similar vessels), semi-empirical methods (building block approach, e.g. WINDOS) and CFD calculations.
Issues related to current loads include low frequency damping of floaters and Vortex Induced Motions (VIM).
The Trials & Monitoring Department can be involved in full-scale measurements and assessment of current loads.
The Offshore Department has a lot of expertise in the field of current loads on FPSOs, Semi-submersibles and Spars. Current loads can be measured in one of MARIN's basins, either by generating current in the basin or by towing the structure. Alternatively, the current loads can be determined by means of wind tunnel tests, carried out at the facilities of one of our regular sub-contractors. Possibilities for the calculation of current loads include the use of data base current load coefficients (using measurement results for similar vessels), semi-empirical methods (building block approach, e.g. WINDOS) and CFD calculations.
Issues related to current loads include low frequency damping of floaters and Vortex Induced Motions (VIM).
The Trials & Monitoring Department can be involved in full-scale measurements and assessment of current loads.
Facilities & Tools
Current load measurements are carried out in the following MARIN facilities :
Current load measurements are carried out in the following MARIN facilities :
- Offshore Basin: DP model tests in combined current, waves and wind
- Shallow Water Basin
- High Speed Basin: model tests in waves
- Depressurised Towing Basin: towing tests
- Deep Water Towing Tank: towing tests
The following tools are used to study current loads :
WINDOS: Assessment of wind loads on ships and offshore structures
DBSHIP: Assessment of mean wave, wind and current forces on ships
PARNASSOS: Calculation of the viscous flow around ships hulls
DBSHIP: Assessment of mean wave, wind and current forces on ships
PARNASSOS: Calculation of the viscous flow around ships hulls
Software Sales
Some software tools are available for commercial use outside MARIN. A complete overview of these software tools for sale can be found under Software Sales.
Some software tools are available for commercial use outside MARIN. A complete overview of these software tools for sale can be found under Software Sales.
Experience
The list below gives a review of current loads projects carried out at MARIN:
The list below gives a review of current loads projects carried out at MARIN:
- LNG-carrier current load measurements (HAWAII JIP, 2006)
- Shenzi TLP (BHP Billiton / MODEC, 2005)
- Bonga FPSO (Shell/Samsung, 2000)
- Ocean Confidence DP model tests (Diamond Offshore, 1998)
- HAWAI JIP
- Current Affairs JIP
Most recent current load papers presented by MARIN
(complete overview of papers can be found under Publications)
(complete overview of papers can be found under Publications)
Predicting Loads On An LNG Carrier With CFD
Fathi, F. (SBM Offshore/Gusto MSC), Klaij, C.M. and Koop, A.H., OMAE ASME 29th International Conference on Ocean, Offshore and Arctic Engineering, Shanghai, 2010
Calculation Of Manoeuvring Forces On Submarines Using Two Viscous-Flow Solvers
Vaz, G.N.V.B., Toxopeus, S.L. and Holmes, S., OMAE ASME 29th International Conference on Ocean, Offshore and Arctic Engineering, Shanghai, 2010
Calculation Of Current Or Manoeuvring Forces Using A Viscous-Flow Solver
Toxopeus, S.L. and Vaz, G.N.V.B., OMAE ASME 28th International Conference on Ocean, Offshore and Arctic Engineering, Honolulu, 2009
Free-Surface Viscous Flow Computations: Validation of URANS Code FreSCo
Guilherme Vaz, Frederick Jaouen and Martin Hoekstra (MARIN), OMAE Conference, Honolulu, 2009
Time Domain Analysis for DP Simulations
Jorrit-Jan Serraris (MARIN), OMAE Conference, Honolulu, 2009
Fathi, F. (SBM Offshore/Gusto MSC), Klaij, C.M. and Koop, A.H., OMAE ASME 29th International Conference on Ocean, Offshore and Arctic Engineering, Shanghai, 2010
Calculation Of Manoeuvring Forces On Submarines Using Two Viscous-Flow Solvers
Vaz, G.N.V.B., Toxopeus, S.L. and Holmes, S., OMAE ASME 29th International Conference on Ocean, Offshore and Arctic Engineering, Shanghai, 2010
Calculation Of Current Or Manoeuvring Forces Using A Viscous-Flow Solver
Toxopeus, S.L. and Vaz, G.N.V.B., OMAE ASME 28th International Conference on Ocean, Offshore and Arctic Engineering, Honolulu, 2009
Free-Surface Viscous Flow Computations: Validation of URANS Code FreSCo
Guilherme Vaz, Frederick Jaouen and Martin Hoekstra (MARIN), OMAE Conference, Honolulu, 2009
Time Domain Analysis for DP Simulations
Jorrit-Jan Serraris (MARIN), OMAE Conference, Honolulu, 2009
Most recent current load 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
CFD for offshore applications
Arjan Koop & Guilherme Vaz, MARIN report, 2010
Frigg QP jacket gets 'on the move' at MARIN
Joris van den Berg, MARIN Report, 2009
New code FreSCo reveals what goes under the surface
Guilherme Vaz, MARIN Report, 2009
The state of Current Affairs
Guilherme Vaz & Olaf Waals, MARIN Report, 2009
Willemijn Pauw & Arjen Koop, MARIN Report, 2010
CFD for offshore applications
Arjan Koop & Guilherme Vaz, MARIN report, 2010
Frigg QP jacket gets 'on the move' at MARIN
Joris van den Berg, MARIN Report, 2009
New code FreSCo reveals what goes under the surface
Guilherme Vaz, MARIN Report, 2009
The state of Current Affairs
Guilherme Vaz & Olaf Waals, MARIN Report, 2009
Contact
For more information on how MARIN can help your organisation with current loads, please contact :
For model test and simulation activities: Offshore Department
knowledge group manoeuvring at manoeuvring@marin.nl
knowledge group Resistance and Propulsion at powering@marin.nl
For full-scale measurements: Trials & Monitoring Department
For more information on how MARIN can help your organisation with current loads, please contact :
For model test and simulation activities: Offshore Department
knowledge group manoeuvring at manoeuvring@marin.nl
knowledge group Resistance and Propulsion at powering@marin.nl
For full-scale measurements: Trials & Monitoring Department