model of cavitation in a thruster

My thruster is cavitating. What do I do?

Cavitation appears when the thruster propeller draws air from the surface, resulting in severely reduced thrust performance and significantly increased noise.

  • Consider upgrading to a proportional thruster system (all Sleipners thrusters produced after 1999 can be upgraded) that allows you to use the thruster at variable speed and to increase the thrust gradually, significantly reducing the risk of cavitation.
  • If you have an old 4-blade propeller, consider upgrading to the 5-bladed Q-propeller, designed to reduce cavitation (and noise), as the skewed propeller blade shape works more efficiently in a turbulent water flow.
  • Verify that there are no sharp edges on the tunnel openings. We have made a video showing the difference between a tunnel's rounded edges and sharp tunnel edges, which can be viewed here.
  • For stern thruster installations, a too shallow installation might suck air from the surface, resulting in cavitation and increased noise. Mounting cowls on the top end of the stern tunnel might reduce this problem significantly.