General information
Cavitation is the transition of liquid water to vapour in low pressure areas. Cavitation develops spontaneously when the local pressure in a fluid drops below the saturated vapour pressure of water. This phenomenon is in fact the boiling of water at room temperature, not by heat but by reducing the pressure. Cavitation bubbles of varying size collapse fiercely when entering a area of higher pressure. The collapse of the cavitation bubbles causes high-pressure shockwaves in the fluid. Periodic fluctuations of the pressure field as caused by the dynamics of the cavitation on the rotating propeller blades excite the ship hull, a feature which can cause vibration and noise. Under certain conditions cavitation can also cause material erosion.
Cavitation is the transition of liquid water to vapour in low pressure areas. Cavitation develops spontaneously when the local pressure in a fluid drops below the saturated vapour pressure of water. This phenomenon is in fact the boiling of water at room temperature, not by heat but by reducing the pressure. Cavitation bubbles of varying size collapse fiercely when entering a area of higher pressure. The collapse of the cavitation bubbles causes high-pressure shockwaves in the fluid. Periodic fluctuations of the pressure field as caused by the dynamics of the cavitation on the rotating propeller blades excite the ship hull, a feature which can cause vibration and noise. Under certain conditions cavitation can also cause material erosion.
Services & Activities
The Propulsors and Cavitation Knowledge Team of MARIN offers its expertise on a wide range of cavitation related topics. Most common are the evaluation of propeller designs on cavitation related pressure fluctuations to prevent ship vibration problems and the assessment of the risk of cavitation erosion.
In its history MARIN has tested a vast number of propellers now contained in its stock of models. For ships such as ferries and cruise liners for which comfort aspects are essential MARIN assists their customers in meeting strict design requirements of today. For naval applications MARIN offers their experience in designing low-noise propellers. These propellers have a delayed inception of cavitation as caviation is a primary noise source. For propellers of merchant ships a compromise between the propulsive efficiency and cavitation hinderance is aimed for from the early start of the design. Verification of the cavitation performance by model experiments is often requested by ship owners.
The Propulsors and Cavitation Knowledge Team of MARIN offers its expertise on a wide range of cavitation related topics. Most common are the evaluation of propeller designs on cavitation related pressure fluctuations to prevent ship vibration problems and the assessment of the risk of cavitation erosion.
In its history MARIN has tested a vast number of propellers now contained in its stock of models. For ships such as ferries and cruise liners for which comfort aspects are essential MARIN assists their customers in meeting strict design requirements of today. For naval applications MARIN offers their experience in designing low-noise propellers. These propellers have a delayed inception of cavitation as caviation is a primary noise source. For propellers of merchant ships a compromise between the propulsive efficiency and cavitation hinderance is aimed for from the early start of the design. Verification of the cavitation performance by model experiments is often requested by ship owners.
Facilities & Tools
Cavitation investigations are carried out in the following MARIN facilities:
Cavitation investigations are carried out in the following MARIN facilities:
- Depressurised Towing Tank (DTT): Cavitation observation and measurements of the pressure fluctuations on the hull above the cavitating propellers at a ship model
- Cavitation Tunnel (CT): Cavitation research involving dedicated test set-ups that are not feasible in the DTT.
For cavitation related issues a large number of experience based tools and CFD programs are available.
The main tools used are:
The main tools used are:
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 cavitations projects carried out at MARIN:
The list below gives a review of cavitations projects carried out at MARIN:
- TIPVOR (RNN/US) 1996-2000
- AFDEASR 1990
The following Joint Industry Projects (JIPs) were focussed on cavitation:
- CoCa (2000-2003)
Most recent cavitation related papers presented by MARIN
(complete overview of papers can be found under Publications)
(complete overview of papers can be found under Publications)
The partial cavity on a 2D foil revisited
Hoekstra, M. and Vaz, G., CAV2009, 2009
Modeling and analysis of a cavitating vortex in 2D unsteady viscous flow
Bosschers, J. , CAV2009 7th International Symposium on Cavitation, 2009
Computation of hull-pressure fluctuations due to non-cavitating propellers
Lafeber, F.H., Wijngaarden, H.C.J. van and Bosschers, J., SMP 1st International Symposium on Marine Propulsors , 2009
Investigation of hull pressure fluctuations generated by cavitating vortices
Bosschers, J., SMP 1st International Symposium on Marine Propulsors, 2009
Investigation of the resonance frequency of a cavitating vortex
Bosschers, J., NAG-DAGA International Conference on Acoustics, 2009
Hoekstra, M. and Vaz, G., CAV2009, 2009
Modeling and analysis of a cavitating vortex in 2D unsteady viscous flow
Bosschers, J. , CAV2009 7th International Symposium on Cavitation, 2009
Computation of hull-pressure fluctuations due to non-cavitating propellers
Lafeber, F.H., Wijngaarden, H.C.J. van and Bosschers, J., SMP 1st International Symposium on Marine Propulsors , 2009
Investigation of hull pressure fluctuations generated by cavitating vortices
Bosschers, J., SMP 1st International Symposium on Marine Propulsors, 2009
Investigation of the resonance frequency of a cavitating vortex
Bosschers, J., NAG-DAGA International Conference on Acoustics, 2009
Most recent cavitation related articles written for MARIN Report:
(complete overview of articles can be found under Publications)
(complete overview of articles can be found under Publications)
Measuring success
MARIN Report, 2009
Oasis of the Seas
Giedo Loeff, Jaap van Heerd & Reint Dallinga, MARIN report, 2009
New borescope technology
Ivo van der Hout, MARIN report, 2009
High speed Cavitation Observation through a 12 mm hole
Ivo van der Hout, MARIN Report, 2007
Color Fantasy
Giedo Loeff, Jaap van Heerd & Jan-Bart Verkuyl, MARIN Report, 2006
MARIN Report, 2009
Oasis of the Seas
Giedo Loeff, Jaap van Heerd & Reint Dallinga, MARIN report, 2009
New borescope technology
Ivo van der Hout, MARIN report, 2009
High speed Cavitation Observation through a 12 mm hole
Ivo van der Hout, MARIN Report, 2007
Color Fantasy
Giedo Loeff, Jaap van Heerd & Jan-Bart Verkuyl, MARIN Report, 2006
Contact
For more information on how MARIN can help your organisation with the issue of cavitation, please contact the Propulsors and Cavitation Knowledge Team at: propulsors@marin.nl
For more information on how MARIN can help your organisation with the issue of cavitation, please contact the Propulsors and Cavitation Knowledge Team at: propulsors@marin.nl