CRP Contra Rotating Propellers – The optimum electric propulsion system.

“Potential savings of CRP are assessed to be in the order of 6-20% of the power consumption with an average of 13%, although higher figures may be presented by industry for specific case”.
Contra Rotating Propellers (CRP)
Brunvolls core competence in propulsion and gearbox design has been utilised in this new series of the Contra Rotating Propulsion System -a combination of known technologies, available in a range from 1,5 to 5,5 MW.
This is an “off the shelf” series of standard configurations consisting of 2 asynchronous electric motors and variable frequency drives, standardised gearboxes and propellers with predefined diameter and rpm, with BruCon Remote Control and Monitoring System.
Blade designs will be customised to the ship for optimum performance.
Brunvoll CRP may also be optionally configured for other prime mover solutions, for example a combination of electric motors and combustion engines.
A configuration of fixed pitch propellers individually driven through a unique shaft-in-shaft system by electric motors. This propulsion system recovers part of the slipstream rotational energy, which is lost with single propeller configurations, and thereby enhances the hydrodynamical efficiency. The blade numbers of the two propellers are different to avoid vibrational problems. The aft propeller diameter is smaller in order to stay within the slipstream contraction from the forward propeller. The system can be driven by any type of electric motors.