Cavitation
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.

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.

Facilities & Tools
Cavitation investigations are carried out in the following MARIN facilities:

  • Depressurised Wave Basin: 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 (such as ReFRESCO, which developments started to enable the calculation of cavitation in viscous-flows) are available.
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.

Experience
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)

Waterjet System Performance and Cavitation Test Procedures
Dang, J., Liu, R. and Pouw, C.P., Third International Symposium on Marine Propulsors (SMP), Launceston, Tasmania, 2013

Scale effects on hull pressure fluctuations due to cavitating propellers
Bosschers, J. and Wijngaarden, E. van, 10th International Conference on Hydrodynamics (ICHD), St. Petersburg, Russia, 2012

High-Speed Video Observations and Acoustic-Impact Measurements on a NACA 0015 Foil
Rijsbergen, M.X. van, Foeth, E.J., Fitzsimmons, P. and Boorsma, A., 8th International Symposium on Cavitation (CAV), Singapore, 2012

Efficient Numerical Simulation of Unsteady Cavitating Flows Using Thermodynamic Tables
Khatami, F., Koop, A. H., Weide, E. T. A. van der, and Hoeijmakers, H. W. M., 8th International Symposium on Cavitation (CAV), Singapore, 2012

Numerical Study on Collapse of a Cavitating Cloud of Bubbles
Loo, S. van, Terwisga, T. J. C. van, Hoeijmakers, H. W. M. and Hoekstra, M., 8th International Symposium on Cavitation (CAV), Singapore, 2012

Most recent cavitation related articles written for MARIN Report:
(complete overview of articles can be found under Publications)

First images of cavitation and ventilation in waves
Gerco Hagesteijn & Joris Brouwer, MARIN Report, 2012

Setting new standards in container ship design
Patrick Hooijmans, MARIN Report, 2012

Meeting the dredger propulsion challenge
Gert-Jan Zondervan, MARIN Report, 2012

MARIN set to open its new Depressurised Wave Basin
MARIN Report, 2011

Measuring success
MARIN Report, 2009

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

Disclaimer | print